Conceptualization of a biorefinery for guishe revalorization

Industrial Crops & Products 138 (2019) 111441

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Conceptualization of a biorefinery for guishe revalorization a,⁎

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b

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L. Díaz-Jiménez , S. Carlos-Hernandez , Diana Jasso de Rodríguez , R. Rodríguez-García

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Cinvestav-Saltillo, SRNyE, Lab for Byproducts Revalorization, Av. Industria Metalúrgica 1062, Parque Industrial Saltillo-Ramos Arizpe, 25900 Ramos Arizpe, Coahuila, México Universidad Autónoma Agraria Antonio Narro, Calzada Antonio Narro 1923, Buenavista, 25315 Saltillo, Coahuila, México

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ARTICLE INFO

ABSTRACT

Keywords: Agave lechuguilla Agro-industrial waste Biomass Integral processing Added value products

The extraction of fiber from Agave lechuguilla Torrey produces 15% of ixtle and 85% of guishe. Guishe is a pulpous by-product, without commercial value, composed of several phytochemicals which could be used as raw material for the synthesis of high added value products. The objective of this work was to conceptualize the integration of transformation processes into a biorefinery scheme, through a mass balance analysis, to identify opportunities for the revalorization of guishe. The processing of 1 ton of guishe is employed as a computing unit. Three fundamental transformation processes were considered: solvent extraction, thermochemical, and biological processing. The information was obtained from ixtle producers and implemented processes at lab scale by the authors. The obtained results show that the transformation of 1 ton of guishe allows producing: 260 kg of saponins, 104 kg of phytochemicals, 7.6 L of ethanol, 24 m3 of hydrogen, 15 kg of biochar and 32 m3 of methane. The evaluated technology is commercially available, and then it is feasible to implement the proposed alternatives at an industrial scale.

1. Introduction The extraction of ixtle from lechuguilla (Agave lechuguilla Torrey) is the main economic activity in rural communities in some semiarid regions of Mexico (Kalan Kash, 2009). Ixtle is a valuable fiber that is used to make ropes, carpets for luxury cars, handbags, brushes and many other items (Castillo Quiroz et al., 2005; Reyes-Agüero et al., 2000). To obtain the fiber it is necessary, first of all, to make a manual collection of the most tender internal leaves of the plant (named “cogollos”). The selection of the leaves is based on criteria of length, color, smoothness, and diameter of the leaves (SEMARNAT, 2003). The process to obtain ixtle involves the carving of the A. lechuguilla leaves either manually or with a simple motorized machine. Additionally, a succulent waste known as guishe is obtained, which is irritating and causes discomfort in the hands at the time of carving. At present, there are initiatives to improve the extraction process to facilitate extraction and avoid risks to the health of producers (Mayorga Hernandez et al., 2001; Reyes-Agüero et al., 2000). A. lechuguilla proliferates in seven states of Mexico (Kalan Kash, 2009) and, it is important to remark that the production of the plant is done naturally, as there are no domesticated crops of A. lechuguilla.

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Therefore, to protect the species, the exploitation of the plant is made only on a specific surface and must be authorized by the Ministry of Agriculture, Livestock, Rural Development, Fisheries and Food (SAGARPA). At the current time, the exploitation of the plant occurs in six of the seven states. To obtain the authorization to exploit A. lechuguilla, the producers should fulfill a Mexican regulation (SEMARNAT, 2003), which determine the requirements at different stages (cogollos harvesting, transport, and storage) to promote sustainable use of species. First, a harvesting authorization request should be submitted to SEMARNAT; this request implies signing up the National Forestry Records, including documentation to prove ownership of the land, surface and annual estimated production, strategies to preserve the ecosystem, preventive strategies against fire, plagues, and other forestry diseases and issues. If the request is accepted, the cogollos harvesting should verify the next criteria: plants with maturity to harvest (cogollo of more than 25 cm); at least 20% of the plants should not be harvested to promote regeneration; adequate tools must be used avoiding cutting the zone of leaflets growth; the production activities should be reported quarterly. Finally, the cogollos transport and storage require also an authorization which is obtained following a similar procedure as for the harvesting authorization.

Corresponding author. E-mail address: [email protected] (L. Díaz-Jiménez).

https://doi.org/10.1016/j.indcrop.2019.06.004 Received 30 January 2019; Received in revised form 23 May 2019; Accepted 2 June 2019 Available online 11 June 2019 0926-6690/ © 2019 Elsevier B.V. All rights reserved.

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Thus, based on these identified alternatives, the objective of this work was to evaluate the integration of a biorefinery scheme, through a mass balance analysis, in order to identify opportunities in the revalorization of guishe; mainly in terms of determining the routes, or the combination of processes more suitable for the best valorization of this by-product.

Table 1 Production of ixtle in Mexico. Mexican State

San Luis Potosí Coahuila Nuevo León Tamaulipas Durango Zacatecas Total

Exploitation authorized surface (ha)

Production (ton) Cogollo

Ixtle

Guishe

313428 69368 220852 42132 136734 35850 818364

107191 44879 16715 1926 1590 851 173152

16079 6732 2507 289 239 128 25974

91112 38147 14208 1637 1351 723 147178

2. Methods 2.1. Guishe collection and characterization Guishe was collected from three agricultural localities (ejido) in Coahuila state: Porvenir (lat: 25.550, long: -101.720), Tortuga (lat: 25.833, long: -101.267), and Buñuelos (lat: 25.05, long: -101.183). The fresh guishe was taken after carving by ixtle producers. Immediately, the samples were transported for characterization and revalorization tests. Proximal analysis of guishe (protein, ash, and moisture) was determined following the Association of Official Analytical Chemists methods (AOAC, 1996). The ether extract was determined by the Soxhlet method of the (AOAC, 1996). Quantification of total sugars was performed by the phenol-sulfuric method (Dubois et al., 1956). All measures were performed by triplicate.

Cogollo. Heart with the attached leaf of Agave lechuguilla plant.

On the other hand, there had been initiatives supported by official programs to propose the establishment of cultivations of A. lechuguilla. The project has been developed by the National Institute of Agricultural and Livestock Forestry Research (INIFAP), and it demonstrated that it is possible improving the productivity of ixtle from A. lechuguilla reducing the technic cycles of the plant from 24 to 12 months (Castillo Quiroz et al., 2012). It has been determined that the ixtle represents only 15% of the plant, while the other 85% corresponds to guishe. This by-product currently does not have an exploitation pathway; thus, it lacks commercial value. This material remains opencast disposed of causing soil erosion; also, it is available for animals, such as goats, which could ingest it and reach dehydration and even death. This problem can be seen more clearly when considering data on the production of ixtle and guishe (Table 1). There is a global average yield of ixtle production per hectare of lechuguilla of γig = 0.032, and the corresponding one for guishe is γgg = 0.18. In other words, for each hectare of authorized exploitation, 32 kg of ixtle and 180 kg of guishe are obtained on average. In the state of Coahuila, the main area of interest of this study, the production yields of ixtle and guishe are γig = 0.097 and γgg = 0.55, respectively; being the highest yields in the country. In general, the 147,178 tons of guishe obtained are not used; they are open cast disposed, and at a certain moment, they are incinerated to free storage space. Recently, it has been determined that the guishe is composed of several phytochemicals that could be used as raw material for the synthesis of high added value products such as saponins, antifungals and hormones, among others (De la Cerda, 2012; Hernández et al., 2005; Reyes-Agüero et al., 2000; Siller Juarez et al., 2014). In this context, it is necessary to evaluate alternatives for the processing of this by-product and thus extend the chain of use of A. lechuguilla. Several methods have been identified for the revaluation of guishe, such as those presented in Table 2.

2.2. Functional unit definition The functional unit has been established based on the recommendations established in the Life Cycle Assessment methodology (de Brujin et al., 2004; ISO 14040, 2006; ISO 14044, 2006). The functional unit defines the priority function of the product, process, or system to be evaluated in the study to be carried out. Its purpose is to provide a reference to normalize the input and output data. That is, it is the basis of calculation to evaluate a process and to compare it with others. The availability of information and the objectives of the study must be considered to define the functional unit. In addition, it is recommended to take efficiency, durability, and quality standards into account. Aspects such as mandatory characteristics (those for which the product was designed) and positioning (those that allow the preference of consumers) also help in the selection of the functional unit. 2.3. Identification of revalorization processes A literature review is done in order to identify reported methods for the use of biomass from A. lechuguilla. According to the characteristics of the identified methods, the operational basis of the more suitable processes for the revalorization of guishe are described. Each one is considered as a unitary process; the inputs, the outputs, and the operating conditions must be identified. Also, the production yields will be calculated from the data obtained in the characterization of the raw material and information reported in the literature.

Table 2 Identified processes for guishe valorization. Process

Input

Product

Application

Physico-chemical separation

Liquid fraction of guishe

Phytochemicals

Thermic treatment

Solid fraction of guishe

Materials with chemical activity

Gasification

Solid fraction of guishe

Syngas Biochar

Hydrolysis

Fresh guishe

Fermentable sugars

Fermentation

Fermentable sugars from hydrolysis Fermentable sugars from hydrolysis

Ethanol

Agriculture, Pharmaceutic, Cosmetic Catalysis adsorption Remediation Energy Products formulation Fermentation Biodigestion Energy Chemical industry

Anaerobic digestion

Biogas

2.4. Biorefinery structure for guishe transformation From the information obtained in the previous section, a selection of revalorization processes is done, and their integration in a biorefinery structure is proposed. A global mass balance, based in the functional unit, is performed and represented in a Sankey diagram (Lupton and Allwood, 2017). A coupling study and a flow of matter from numerical simulations are also proposed. The processes are implemented in the MatlabSimulink environment, and different operating conditions and scenarios are evaluated. Based on such simulations, the best conditions for the coupling of the processes are established, and the opportunities are identified.

Energy

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3.3. Alternatives for revalorization of guishe

Table 3 Characterization of guishe collected in three localities in the state of Coahuila, Mexico. Parameter (% wt)

Porvenir

Tortuga

Buñuelos

Moisture Ash Crude fiber Volatiles Proteins Total sugars

74.32 ± 4.10 4.31 ± 0.38 1.56 ± 0.09 0.51 ± 0.003 0.53 ± 0.04 20.36 ± 4.53

70.85 ± 4.97 3.65 ± 0.59 1.96 ± 0.04 0.50 ± 0.02 0.43 ± 0.11 11.59 ± 4.25

68.17 ± 5.60 6.74 ± 0.49 1.80 ± 0.16 0.33 ± 0.04 0.48 ± 0.04 8.52 ± 1.00

At December 2018, the Scopus database recorded 80 documents for the term “Agave lechuguilla”; most of them are scientific papers. Around 50% of the documents were published after 2010. This number implies an increasing interest in the study of the plant. The main subject areas where A. lechuguilla is studied are: Agricultural and Biological Sciences, Environmental Science, Earth and Planetary Sciences, Materials Science, and Biochemistry, Genetics and Molecular Biology, which implies a multidisciplinary interest. As the main goal of this work is to promote the integral use of guishe, an analysis of the published documents was performed in order to identify the methods used to take advantage of A. lechuguilla, other than the extraction of ixtle. The methods for biomass processing of A. lechuguilla are presented in Table 4. From this information, it can be concluded that the processing of biomass from plant leaves is the most recurrent subject reported in the literature. Heart with attached leaf bases, ixtle and guishe are less studied, but they are more considered to evaluate their potential for several uses. In most cases, the A. lechuguilla biomass has proven to be an efficient alternative for the different evaluated applications. The two main processes studied for the A. lechuguilla biomass transformation are “extraction” (Alcázar-Medina et al., 2014; Hernández et al., 2005; Jasso de Rodríguez et al., 2011; Verástegui et al., 2008) and “milling” (Juárez et al., 2007; Medellín-Castillo et al., 2017; Orzua et al., 2009; Romero-González et al., 2009). The “extraction” consists on to separate compounds of interest present in a substance; this extraction is usually done through organic solvents. Currently, alternative methods for extraction are evaluated, such as the use of microwaves and ultrasound, as shown in De la Cerda (2012). Saponins, tannins, and other polyphenols are the main phytochemicals obtained from lechuguilla biomass (Alcázar-Medina et al., 2014; Castillo et al., 2010; Hernández et al., 2005; Jasso de Rodríguez et al., 2011; Mendez et al., 2012; Siller Juarez et al., 2014). The already tested applications for these compounds are as antimicrobial and antifungal. Besides, “milling” is a mechanical process which is usually preceded by drying of biomass. The objective is to reduce the size particle to obtain solid materials which can be activated to function as adsorbents, microorganisms’ carriers, and additives. The reported applications of the materials are: the removal of heavy metals from water (Carlos Hernández et al., 2018b; Medellín-Castillo et al., 2017; RomeroGonzález et al., 2005), bacteria immobilization (Orzua et al., 2009), reinforcement of polymers (Velásquez-Martínez et al., 2011), and formulation of cement composites (Juárez et al., 2007). Moreover, sequential transformation is also a studied alternative. Two main topologies are identified: biochemical and thermochemical. The first includes a pretreatment stage (autohydrolysis and acid treatment) of heart with attached leaf bases followed by different configurations for fermentation in order to obtain bioethanol (Díaz-Blanco et al., 2018; Morales-Martínez et al., 2017; Ortiz-Méndez et al., 2017). The last one considers the thermochemical treatment (pyrolysis and combustion) of the solid fraction of guishe and the activation of the treated material to serve as an adsorbent for metals removal from water and carrier of microorganisms (Carlos Hernández et al., 2018b; Villarreal Sánchez, 2019). Sequential transformation seems to be more complex; however, it allows increasing yields and diversifying the products which could be obtained, and then applications of lechuguilla biomass. Even if the use of the plant leaves is an interesting alternative (easy, economical and efficient) to revalorize A. lechuguilla, the applications at large scale imply competition with the current application: the obtaining of ixtle. Usually, the ixtle producers are proud of their activity, and it is hard to convince them to change the way of taking advantage of their resources. In order to deal with this situation, the revalorization of guishe is a feasible alternative to avoid competition with the ixtle extraction, which is the main economic activity of several rural

3. Results and discussion 3.1. Guishe characterization The bromatological characterization of the samples of guishe, collected in three localities of the state of Coahuila are presented in Table 3. From these results, it can be concluded that guishe is composed of two main fractions: liquid and solid. The liquid fraction is predominant; around 70% of guishe is liquid as the moisture content is ranged on this value. This value implies a transformation by either chemical extraction or biological processes. Meanwhile, the remaining 30% is solid, which requires more complex processes to be transformed. Differences in the parameters are observed depending on the origin of the raw material. The greatest variation corresponds to the content of sugars; the highest percentage is obtained in Porvenir, where the content is 20.3%; this is almost twice the one at Tortuga and more than twice the one at Buñuelos. It can be concluded that there is a direct, though not linear, the relationship between sugar content and moisture: the higher the moisture, the higher the sugar content. The average of the three localities is 13.5%, which implies the raw material has the potential for the production of polysaccharides or oligosaccharides, which have application in fermentation processes or for the formulation of products for the agri-food industry (Di Donato et al., 2014; MoralesMartínez et al., 2017). The ash content implies that most of the raw material can be transformed by thermochemical processes in order to obtain products with a commercial value; while less than 7% remains as residual material. However, these ashes may find application in the formulation of other products, such as cement, soil improvers, and activated carbons, among others (James et al., 2012). 3.2. Definition of the functional unit As the functional unit is the reference for sizing the proposed processes to guishe revalorization, this can be related to three aspects of the production chain of interest: "authorized surface for the exploitation of A. lechuguilla", "volume of production of ixtle ", and "volume of production of guishe ". The first two aspects are directly related to the production of lechuguilla. The exploitation surface and the production volume of ixtle are part of the current chain of use of A. lechuguilla. The volume of production depends on the productive characteristics of the exploitation surface. Likewise, the volume of guishe production is a consequence of the two previous aspects. Besides, this aspect is not found in the current value chain of the studied plant. Thus, it can be inferred that the "volume of guishe production" indirectly includes aspects of the use and production surface of ixtle. Also, the processing of the guishe is what is proposed as an alternative to extending the value chain. Then, to facilitate the mass balance analysis, 1 ton is considered as a production unit. Therefore, the selected functional unit for this study is: the processing of 1 ton of guishe. 3

4

Ixtle

Leaves

Leaves Leaves Leaves

Leaves

Leaves Leaves Leaves

Leaves Leaves Leaves

Heart with attached leaf bases Heart with attached leaf bases

Heart with attached leaf bases Purified fibers Guishe

Boiling and cutting

Liquid-Solid purification

Solid-Liquid extraction Solid-liquid extraction Drying and milling

Drying and milling

Drying and milling Solid-Liquid extraction Solid-Liquid extraction

Solid-Liquid extraction Solid-Liquid Extraction Alkaline / organosolv pulping

Autohydrolysis and enzymatic digestion Autohydrolysis

Acid pretreatment

NR-not reported.

Combustion and formulation

Filtration Drying and milling Pyrolysis and activation

Guishe Guishe Guishe (Solid fraction) Guishe (solid fraction)

Ixtle Ixtle

Mechanical size reduction Mechanical size reduction

Chemical functionalization Filtration

Raw material

Method

Solid material

Solid fraction Adsorbent Adsorbent

Cellulose derivatives Liquid fraction

–

22% NR –

17–21% 78%

68 g/g (87%)

Solid: Glucan 40.9%, xylan 1.52 %, lignin 44.25 Liquid: glucose 0.26 g/L, xylose 6.43 g/L

Hydrolysates

Glucose

59 g/L

26.94 mg/g 19% 49%/70.8%

NR 4200 mg/L NR

NR

NR 17 mg/g NR

96%

–

– NR

Glucose

Tannins Saponins Cellulose pulp

Bioimmobilizer Tannins Poliphenolic compounds

Adsorbent

Purified fibers (Cellulose, hemicelluloses, lignin) Liquid material Saponins Adsorbent

Support for nanoparticles

Solid material Solid material

Bioinoculants

Phytochemical extraction Pb (II) removal from water As adsorption from water

Chemical industry Saponin extraction

Low efficiency

84.23 mAU*s Adsorption capacity: 25 mg/g 100 % at 120 min

Ethanol: 10.4 g/L Ethanol production: 14.3 g/L (73.3%) Non-tested 361 mg/g

Ethanol: 45 g/L

Ethanol: 53.7 g/L

Separate hydrolysis and fermentation (SHF) Simultaneous saccharification and fermentation (SSF) Prehydrolysis and SSF Fermentation

Fermentation

70% 99.8% Good quality: better for alkaline pulping Ethanol production: 51.4 g/L

Low immobilization 37% 100%

Adsorption: 95 mg/g

> 50 % Non-tested 56%

Good mechanical properties and high bacteria inhibition 9%

High tensile capacity Resistance > 9 times higher

Highlights

Antibacterial Cu removal from water Handmade paper

Immobilization carrier Antifungal Antifungal

Continuous Cr removal from water

Antimicrobial and antifungal Pharmaceutic industry Cr removal from water

Grafting for biopolymers

Cement composites Reinforcement of polyester resin Antibacterial

Revalorization test

Product

Yield

Results

Output

Table 4 Reported methods for revalorization of biomass from Agave lechuguilla.

(Vieira et al., 2002) (Siller Juarez et al., 2014; Siller Juárez, 2012) (De la Cerda, 2012) (Medellín-Castillo et al., 2017) (Carlos Hernández et al., 2018b) (Villarreal Sánchez, 2019)

(Díaz-Blanco et al., 2018)

(Morales-Martínez et al., 2017)

(Ortiz-Méndez et al., 2017)

(Antonio Cruz et al., 2002, 1999) (Verástegui et al., 2008) (Hernández et al., 2005) (Romero-González et al., 2005) (Romero-González et al., 2009) (Orzua et al., 2009) (Castillo et al., 2010) (Jasso de Rodríguez et al., 2011) (Mendez et al., 2012) (Alcázar-Medina et al., 2014) (Jiménez Muñoz, 2017)

(Juárez et al., 2007) (Velásquez-Martínez et al., 2011) (Morales-Luckie et al., 2016)

Ref.

L. Díaz-Jiménez, et al.

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of guishe (kg), Rm the medium resistance (m−1) and c the mass concentration of solids in guishe. The simulation is based on lab scale experiments data (De la Cerda, 2012; Siller Juárez, 2012), and the best result for the filtration process is presented in Fig. 2. The required time to complete the separation of the fractions is around 1.5 h. As the liquid fraction density is around 1.3 kg⋅L−1, a maximum of 591 L can be recovered from 1000 kg of guishe; then, the maximum solid fraction is near to 230 kg. The most relevant parameter to achieve this solid-liquid separation is pressure, which is frequently limited by mechanical components and influence on the cost of equipment, as explained in Chhabra and Basavaraj (2019). Then, it is important to consider this economic aspect to scale up the laboratory experiment. For the liquid fraction, two sequential liquid-liquid extraction processes are proposed; the first one to obtain saponins and the other one to obtain phytochemicals, which are the main components of this fraction. Saponins are raw material for the formulation of products in the environmental, pharmaceutical, and cosmetic sector (Liu et al., 2017; Moghimipour and Handali, 2015; Siller Juarez et al., 2014). The other phytochemicals find application in the agricultural and pharmaceutical industry (Castillo et al., 2010; Jasso de Rodríguez et al., 2011; Mendez et al., 2012). Half of the available volume of liquid fraction is used as raw material for each process. As for the filtration, simulations were performed considering the equations governing the extraction process (Foley, 2002):

Fig. 1. Flow diagram of the proposed biorefinery of guishe.

communities. In this sense, it is supposed that most of the already evaluated processes for leaves and heart of the plant could be applied to guishe as only the ixtle has been removed and all the other compounds should be available. 3.4. Process integration for guishe revalorization The proposed strategy for the revalorization of guishe considers processes already evaluated for A. lechuguilla biomass and some other identified as potential alternatives, specifically, gasification for syngas production and anaerobic digestion for wastewater treatment and thermal energy production through biogas combustion. The objective of including these processes is to contribute to the energetic autonomy of the guishe biorefinery. The structure of the integrated process is shown in Fig. 1. The main interest is the revalorization of guishe; then, the pathway to transform ixtle is not presented in detail. After the carving of leaves for ixtle extraction and the production of guishe, a filtration process of the last one is projected to separate the solid from the liquid fraction; this separation should ease the selection of processes to obtain added value products from both solid and liquid fraction. Three kinds of products are identified: primary, secondary, and additional. Primary products are the target of the main processes considered in the guishe transformation. These processes are solvent extraction, gasification, pyrolysis, and fermentation; therefore, the primary products are saponins and phytochemicals, hydrogen, biochar, and ethanol, respectively. Secondary products correspond to compounds obtained either implicitly with the primary ones or from the wastewater treatment: methane and ashes from gasification and methane, hydrogen and sludges from anaerobic digestion. The additional products are compounds which can be produced but that there are not quantified in this study; all of them are classified as volatile compounds. The objective of the filtration process is to do a maximal separation of guishe fractions. A simulation study is done by considering the main parameters involved in this process. The dynamics of filtration can be described by the next equations system (1), which is described in detail by Chhabra and Basavaraj (2019).

dGL A P = dt µ ( GS + Rm ) dGS G =c L dt A

dEG K A = m (EG dt V dGL = VGL EG dt

D GL ) (2)

where EG is the extracted compound from guishe (saponins or phytochemicals), Km the total coefficient of mass transfer, A the interphase area, D the distribution coefficient, V the total volume and VGL the volume of the liquid fraction of guishe. For the saponins extraction, ethyl acetate is considered since this solvent has been used for this application at lab scale (Siller Juarez et al., 2014); as mentioned above, the liquid guishe volume is 591 L. The time of simulation is 7 h, as this period was considered at lab scale experiments. The results from simulations are introduced in Figs. 3a and 3b. Around 260 kg of saponins can be extracted from the liquid fraction of guishe, which corresponds to a yield of 33%. This saponins production is higher than the reported previously (Alcázar-Medina et al., 2014; Hernández et al., 2005); in those studies, saponins were obtained from leaves instead of guishe. Besides, the yield obtained from the extraction simulation is according with the production reported by Siller Juarez et al. (2014) (36% from liquid guishe), since the operating conditions considered are similar. In addition, after the saponins extraction, the remaining liquid is near to 400 L, which is now available for a second extraction in order to obtain some other phytochemicals. For this second extraction, methanol is used as solvent, as done at lab scale (De la Cerda, 2012). Also, the same time as for saponins extraction has been considered for this case. More than 100 L of phytochemicals can be obtained from this process, and 315 L of wastewater are generated from the extraction. The simulation results are presented in Fig. 3c and d. The amount of extracted phytochemicals seems to be very large in comparison with the production from leaves obtained by other authors (Castillo et al., 2010; De la Cerda, 2012; Mendez et al., 2012). It is important to remark that the extraction process requires the use of a specific solvent to a specific compound; therefore, it is feasible to explore different alternatives since liquid guishe could contain several flavonoids (Castillo et al., 2010; Jasso de Rodríguez et al., 2011; Mendez et al., 2012). The simulation study shows that it is possible to reach high yields in the sequential extraction.

(1) 3

where GL is the liquid fraction of guishe (m ), A the filtration area, ΔP the difference of pressure (N⋅ m−2), μ the viscosity (N⋅s⋅ m−2), α the specific resistance of solid accumulation (m⋅ kg−1), GS the solid fraction

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Fig. 2. Separation of the liquid and solid fraction of guishe.

Concerning the solid fraction of guishe, due to its high fiber content, three revalorization pathways are proposed: hydrolysis-fermentation, gasification, and pyrolysis. The whole of the solid fraction of guishe was divided by three, and each part is considered as input for one transformation pathway. Through hydrolysis, it is feasible to obtain fermentable sugars which, in turn, are the raw material for obtaining ethanol or organic acids by fermentation (Díaz-Blanco et al., 2018; Morales-Luckie et al., 2016; Ortiz-Méndez et al., 2017) The enzymatic hydrolysis is represented by the system (3) as reported by Kadam et al. (2004). The mathematical model considers the production of fermentable sugars (SF) from cellulose in solid guishe (GS) through a primary transformation to cellobiose (CE). It is considered the whole of fermentable sugars as glucose. In order to include inhibition by the presence of xylose, this transformation is represented by the Michaelis-Menten kinetic model, as follows:

dGS = dt

1+

k1r E1B RS GS CE + KSF + K 1ICE

1ISF

K1IX

dCE k1r E1B RS GS = 1.056 dt 1 + KCE + K SF + 1ICE

k2r (E1B + E2B ) RS GS 1 + KCE + K SF + K X

X

1ISH

2ICE

X K1IX

dSF k (E + E2B ) RS GS = 1.111 2r CE1B dt 1+ K + K SF + K X 2ICE

(

2ISF

k3r E2F CE

K3M 1 +

SF K3ISH

+

X K3IX

2ISF

(

2IX

k3r E2F CE

K3M 1 +

SF K3ISH

+

X K3IX

) + CE

+ 1.053

2IX

) + CE (3)

The parameters for the simulation were adapted from Kadam et al. (2004) and from data reported by Díaz-Blanco et al. (2018). An additional equation is introduced in order to represent the production of sludge from enzymatic hydrolysis. After that, the fermentable sugars

Fig. 3. a, b) Saponins extraction from the liquid fraction of guishe. c, d) Phytochemicals extraction from the liquid fraction of guishe. 6

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(modeled as glucose) are sequentially transformed by fermentation in order to produce bioethanol (Eth). The fermentation simulation is performed considering Saccharomyces cerevisiae as fermentative microorganisms (XF), the kinetics of the biological reaction is represented by the Haldane model since it allows to consider the microorganisms inhibition and saturation. The fermentation is represented by the equation system (4), which is adapted from the one described in Oliveira et al. (2016).

µmax SF dXF = dt Ks + SF + dSF = dt dEth = dt

2 SF Ki

Eth Eth max

1

µmax SF YEth / SF Ks + SF + µmax SF Ks + SF +

2 SF Ki

2 SF Ki

simulation of the system (4) and considering the fermentable sugars produced by enzymatic hydrolysis is 7.5 L. This corresponds to an 83% of sugars transformation and a global yield ethanol/solid guishe of ˜10%. These results are lower than reported by Ortiz-Méndez et al. (2017) and Díaz-Blanco et al. (2018), where a pretreatment of raw material is included. The consolidated approach studied by those authors was not considered in this work since the technology at higher scales is not commercial yet, and the current operation seems to be complex and high cost. However, the high yields could compensate for the inconvenient of traditional approaches; then, consolidated bioprocessing is proposed as an alternative for future works regarding guishe biorefining. The second pathway for the transformation of solid guishe is gasification, which is a thermochemical reaction at high temperature and controlled oxygen conditions. The main product is synthesis gas (H2 and CO), mixed with N2, CO2, sulfides, and H2O, depending on the raw material. Waste such as vitrified ash can be used in the construction industry or soils recovery (James et al., 2012). The gasification reaction of lignocellulosic biomass is represented by the next equation (Wang and Kinoshita, 1993).

n

XF

XF

XF (4)

where μmax is the maximal growth rate, Ks and Ki the saturation and inhibition coefficient, respectively; n represents the ethanol toxic power, Eth is the maximal ethanol production, α is a coefficient related to the transformation yield. The corresponding values were deduced from Oliveira et al. (2016) and Díaz-Blanco et al. (2018). The obtained results from the sequential enzymatic hydrolysis and fermentation are presented in Fig. 4. Around 9 kg of fermentable sugars and near to 65 kg of sludge are obtained in two weeks from 77 kg of the solid fraction of guishe, as shown in Fig. 4(a, b). The sugars production yield is ˜11%, this is a low yield in comparison with the reported by Ortiz-Méndez et al. (2017) and Díaz-Blanco et al. (2018); in those researches, heart with attached leaf bases were pretreated before the enzymatic hydrolysis leading to high yields at lab scale: 13–51% and 68%, respectively. An inconvenient of the enzymatic hydrolysis is the slow reaction speed; however, it has been tested for the pretreatment of lignocellulosic material to obtain some valuable products, such as glucose, biopolymers, and bioethanol (Díaz-Blanco et al., 2018; Jiménez Muñoz, 2017; Morales-Martínez et al., 2017; Ortiz-Méndez et al., 2017). Concerning fermentation, the ethanol production obtained from the

CH O + yO2 + zN2 + wH2 O= x1 C + x2 H2 + x3 CO + x 4 H2 O + x5 CO2 + x 6 CH4 + x 7 N2

(5)

For the case of guishe, some other elements should be included in the reaction such as calcium, as this is present in the material. In the equation system (6), it is presented the corresponding equations to the modeling of guishe degradation, as well as hydrogen and methane production; the complete kinetic model is described in detail in (Wang and Kinoshita, 1993).

dC = 1 (G ) + 2 (G ) + 3 (G ) dt dH2 = 3 2 (G ) + 2 3 ( G ) dt dCH4 = 3 (G ) + 4 (G ) dt

4 (G )

(6)

where C stands for carbon in guishe, G for guishe, H2 for hydrogen and CH4 for methane; υ1, υ2, υ3 and υ4 are the rate equation for the reactions

Fig. 4. a, b) Production of glucose from enzymatic hydrolysis of the solid fraction of guise. c, d) Ethanol production from fermentable sugars obtained by enzymatic hydrolysis.

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Fig. 5. a, b) Hydrogen and methane production from gasification of the solid fraction of guishe. c, d) Biochar production from pyrolysis of the solid fraction of guishe.

involved in gasification; they are modeled based on the LangmuirHinshelwood mechanism. The obtained results from simulations are shown in Fig. 5a and 5b. Around 35 m3 of gas with high calorific value (hydrogen and methane) are obtained from the gasification of 77 kg of solid guishe; moreover, the transformation yield is near to 100%. The energy content considering the low heat value (LHV) is around 12 kWh∙m−3 (43.2 MJ m−3), which is into the interval reported in other works for other biomasses (Mazaheri et al., 2019). This amount of gas can be used to provide energy to some of the processes integrating the biorefinery of guishe. At present, there exist commercial technology to obtain electricity from methane and hydrogen with feasible efficiencies (Carlos Hernandez and Diaz Jimenez, 2018). However, it is important to consider that some other gases, such as carbon monoxide and volatile gases, are produced from this thermo-chemical transformation; then the manipulation of gasification products should consider safe condition. Nevertheless, the main advantage is the high biomass transformation yields (Mazaheri et al., 2019). Pyrolysis is the other thermochemical process considered for guishe revalorization. It is an incomplete combustion taking place in the absence of oxygen at temperatures around 500 °C. This process is also known as coking or carbonization, and it has traditionally been used for the production of charcoal, but gaseous and liquid products are also obtained (Babu and Chaurasia, 2003). The model used for the simulation study involves three main reactions and are modeled as follows (Babu and Chaurasia, 2003):

Solid _Guishe (Volatiles + Gases )1 = VG1 (Char )1 = Ch1 VG1 + Ch1 (Volatiles + Gases )2 + (Char ) 2 = VG2 + Ch2

dGS = k1 GSn1 + k2 GSn2 dt dg1 = k1 GSn1 k3 g1n2 ch1n3 dt dch1 = k2 GSn1 k3 g1n2 ch1n3 dt dg2 = k3 g1n2 ch1n3 dt dch2 = k3 g1n2 ch1n3 dt

(8)

where Gs is the solid fraction of guishe, g1 and ch1 are the intermediary gases, and char (produced in the first two reactions), respectively and g2 and ch2 are the final products from the third reaction; ki represents the different rate reaction constants, and they are computed following a based Arrhenius model. The main interest of pyrolysis of guishe is the production of biochar since this compound can be used in several applications such as adsorbent, catalysts, bacteria carrier and many others (Carlos Hernández et al., 2018b; Villarreal Sánchez, 2019). As illustrated in Fig. 5c and d, the solid fraction of guishe transformation yield is near to 100%, and around 15 kg of biochar (˜19%) can be synthesized from this process. The transformation yield and the biochar production yield agree the reported by other authors for different raw materials (Babu and Chaurasia, 2003; Elkhalifa et al., 2019; Yu et al., 2019). Also, pyrolysis generates products with energy potential such as oils and gases (Yu et al., 2019); this aspect should be incorporated as a research topic for future works in the guishe transformation. On the other hand, the wastes produced from the different processes for the transformation of 1 ton of guishe is estimated on 540 L. For this reason, the management of these wastes by an anaerobic treatment is considered. This method includes an additional benefit: the production of biogas, which contains methane and even hydrogen. It is supposed that the sludge from hydrolysis and fermentation, and the wastewater from extraction processes have a high content of organic material. All

(7)

The kinetics of the pyrolysis process is represented by Eq. (8).

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these wastes can be transformed by anaerobic consortia in order to produce biogas and other products (Carlos Hernández et al., 2018a; Fedailaine et al., 2015; Mao et al., 2015; Vasco-correa et al., 2018). The mass balance for the treatment of wastewater by anaerobic digestion is represented by equations system (9), and it is adapted from Fedailaine et al. (2015).

dX = D (Xi dt dS = D (Si dt

X) + µ X Sf )

diagram is constructed (Fig. 7) to better illustrate the mass balance corresponding to the use of A. lechuguilla. As said before, the main interest of this work is the reassessment of guishe; for this reason, the pathway to transform the ixtle is not presented in detail. The numbers in the nodes of the Sankey diagram correspond to the mass of the respective component. From the mass balance study, it can be deduced that saponins and phytochemicals are some of the most important products which can be obtained from the liquid fraction of guishe. In this context, it is worth to mention that the solvent extraction is a commercial technology and it is available at industrial level (Wennersten, 2004); then, this is feasible to implement it for the proposed biorefinery. The transformation of the solid fraction of guishe seems to be less attractive as few amounts of products are obtained from simulations. This situation is due to the amount of raw material as the solid fraction is < 50% of the solid fraction; this implies the selected processes uses a few amounts of biomass (only 77 kg). Besides, even if the technology (gasification, pyrolysis, enzymatic hydrolysis, and fermentation) are commercially available, the application to guishe requires to be optimized. In both cases (liquid and solid fractions), an economic study should be performed in order to determine the commercial value of the different products; this could modify either the structure of the proposed revalorization scheme or the flows for each process. On the other side, the node named “volatiles” involves the compounds which are not considered as products in the different transformation processes, for example: organic acids from fermentation, other flavonoids from extraction, gases from pyrolysis and gasification. Deeper studies are required in order to determine if it is possible to recover some of these compounds. Finally, the whole of the residual material (wastewater from solvent extraction, sludge from enzymatic hydrolysis and fermentation) are sent to a treatment process based on anaerobic digestion. This method is selected since the volume of wastewater is not too high, the concentration of organic material is supposed to be also adequate for an anaerobic bioreactor, and most important, it is possible to produce methane as an energy source, sludge as biofertilizer and treated water. This guishe integrated conversion can be classified, according to the Status Report Bioenergy 2007, as a Two Platform Concept Biorefinery

kd X

(yx + ksx

kmx ) µ X + ys (yCH 4 + yCO2 + yH 2 + yNH 3 )

µX dCH4 = yCH 4 µ X dt dCO2 = yCO2 µ X dt dH2 = yH 2 µ X dt dNH3 = yNH 3 µ X dt (9) where X, S, CH4, CO2, H2, and NH3 is anaerobic bacteria consortia, organic material in wastewater, methane, carbon dioxide, hydrogen, and gaseous ammonia, respectively. The bacteria growth rate (μ) follows the Haldane model in order to consider inhibition and saturation. The other terms correspond to transformation coefficients The simulation of anaerobic digestion of the organic wastes produced in all the biorefinery processes is presented in Fig. 6. Considering a chemical oxygen demand (COD) of 750 mg L−1 in the wastewater, near to 0.043 g∙L−1 of methane can be obtained as well as 0.0025 g L−1 of hydrogen. The final COD is 120 mg L−1, corresponding to 84%. In addition, considering the volume of wastewater, the generation of 22.7 g of methane and 1.35 g of hydrogen were achieved. That means each kg of COD removed produces 0.1 m3 of CH4; wich agrees the reported in the literature (Vasco-correa et al., 2018). This amount of biogas can provide a fraction of the thermal energy required in the biorefinery operation (Carlos Hernández et al., 2018a). From the results obtained in the numerical simulations, a Sankey

Fig. 6. Methane and hydrogen production from anaerobic digestion of organic wastes.

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Fig. 7. Global mass balance (Sankey diagram) of the guishe transformation.

(TPCBR): a combination of biochemical and thermochemical processes is considered (Cherubini et al., 2009). On the other side, since the main product obtained is saponins (from solvent extraction) and hydrogen (from gasification), according to the International Energy Agency (Bioenergy Task 42), the guishe transformation structure can be classified as Organic solution and syngas platform biorefinery for chemicals and biopolymers from lignocellulosic residues (Cherubini et al., 2009). Cebreiros et al. (2017) have proposed a biorefinery for biomass from Eucalyptus grandis; they focus on the acetic acid recovery by solvent extraction (as done in this paper for saponins and phytochemicals extraction) and describe the importance of transforming biomass to obtain some other products such as bioethanol, lignin, kraft pulp, and organic acids. The transformation scheme presented in this paper is structured by six main processes, and one wastes treatment stage; this is comparable with the work performed by Neiva et al. (2018); they characterize Eucalyptus globules bark produced by a pulp mill to determine its potential to be transformed in a biorefinery context. Their proposed scheme is composed by six stages: fractioning, extraction one, pulping, extraction two, autohydrolysis and hydrolysis; the authors indicate that it is feasible to obtain fines, bioenergy and filling material, pulp and black liquor, bioactive compounds, saccharides, and lignin, glucose, and ethanol, respectively. A similar approach of the biorefinery proposed in this paper was considered by Gutiérrez et al. (2019); the authors have developed a simulation scheme based on kinetic models of different processes such as kraft pulping process, acid hydrolysis, evaporation and adsorption, fermentation, direct and indirect dimethyl ether synthesis. The global model was used as a tool to determine the potential of lignocellulosic residual biomass (mixtures of forestry, olive and grape pruning, sunflower and sawdust) to produce ethanol, dimethyl ether, synthesis gas, and electricity. The activities developed in view to revalorize guishe match the current biorefinery trends; the use of residual biomass to avoid energy vs. food competition is now a priority. Also, the diversification of products obtained from the biomass conversion is preferred instead of the single bioenergy production (Hassan et al., 2019). In this context, more research and knowledge transfer are required to achieve the integral valorization of biomass.

4. Conclusion Most of the current alternatives to improve the use of A. lechuguilla consider leaves and cogollos; this induces a competition with the extraction of ixtle, which is the main product of the plant. Few studies focus on the revalorization of guishe. It was found that the liquid fraction presents the largest yields (product/functional unit) of production: 260 kg ton−1 saponins, 104 kg ton−1 of phytochemicals. Related to the solid fraction, the yields are small due to the amount of raw material (˜50% of the liquid fraction) and the diversification of proposed processes. The technology for guishe revalorization is commercially available; however, deeper studies are required in order to evaluate the socioeconomic feasibility to obtain more compounds from solvent extraction and to recover valuable gases from gasification and pyrolysis. Acknowledgment Authors thank the support of CYTED through the project P718RT0024 Optimización de los procesos de extracción de biomasa sólida para uso energético. References Alcázar-Medina, F., Proal-Nájera, J., Gallardo-Velázquez, T., Cháirez-Hernández, I., Antileo-Hernández, C., Alvarado-de-la-Peña, A., 2014. Aplication of lechuguilla (Agave lechuguilla Torr.) extracts for copper (II) removal from water models by spherical agglomeration. Rev. Mex. Ing. Química 13, 605–617. Antonio Cruz, R., Mendoza, A.M., Calado Vieira, M., Heinze, T., 1999. Studies on grafting of cellulosic materials isolated from Agave lechuguilla and fourcroydes. Die Angew. Makromol. Chemie 273, 86–90. https://doi.org/10.1002/(SICI)15229505(19991201)273:1<86::AID-APMC86>3.0.CO;2-V. Antonio Cruz, R., Mendoza, A.M., Heinze, T., 2002. Synthesis and characterization of graft copolymers from natural fibers. Int. J. Polym. Mater. Polym. Biomater. 51, 661–674. https://doi.org/10.1080/714975799. AOAC, 1996. Official Methods of Analysis, 16th ed. Association of Official Analytical Chemistry. Babu, B.V., Chaurasia, A.S., 2003. Modeling, simulation and estimation of optimum parameters in pyrolysis of biomass. Energy Convers. Manage. 44, 2135–2158. https://doi.org/10.1016/S0196-8904(02)00237-6. Carlos Hernández, S., Día Jiménez, L., Bueno García, A., 2018a. Potential of energy production from slaughterhouse wastewater. Interciencia 43, 558–565. Carlos Hernandez, S., Diaz Jimenez, L., 2018. The potential for biogas production from agriculture wastes in Mexico. In: Biernat, K. (Ed.), Biofuels - State of Development,

10

Industrial Crops & Products 138 (2019) 111441

L. Díaz-Jiménez, et al. pp. 15–36. https://doi.org/10.5772/intechopen.75457. Carlos Hernández, S., Díaz Jiménez, L., Castilleja Escobedo, O., Gamero Melo, P., 2018b. Preparación y caracterización de un biocarbón funcionalizado con hierro a partir de guishe. XXXVI Congreso Interamericano de Ingeniería Sanitaria y Ambiental 111–116. Castillo, F., Hernández, D., Gallegos, G., Mendez, M., Rodríguez, R., Reyes, A., Aguilar, C.N., 2010. In vitro antifungal activity of plant extracts obtained with alternative organic solvents against Rhizoctonia solani Kühn. Ind. Crops Prod. 32, 324–328. https://doi.org/10.1016/j.indcrop.2010.05.013. Castillo Quiroz, D., Berlanga Reyes, C.A., Cano Pineda, A., 2005. Recolección, Extracción Y Uso De La Fibra De Lechuguilla (Agave Lechuguilla Torr.) En El Estado De Coahuila. Saltillo, Coahuila, Mexico.Recolección, Extracción Y Uso De La Fibra De Lechuguilla (Agave Lechuguilla Torr.) En El Estado De Coahuila. Saltillo, Coahuila, Mexico. Castillo Quiroz, D., Cano Pineda, A., Berlanga Reyes, C.A., 2012. Establecimiento Y Aprovechamiento De Lechuguilla (Agave Lechuguilla Torr.). Jalisco, México.Establecimiento Y Aprovechamiento De Lechuguilla (Agave Lechuguilla Torr.). Jalisco, México. Cebreiros, F., Guigou, M.D., Cabrera, M.N., 2017. Integrated forest biorefineries: recovery of acetic acid as a by-product from eucalyptus wood hemicellulosic hydrolysates by solvent extraction. Ind. Crops Prod. 109, 101–108. https://doi.org/10.1016/j. indcrop.2017.08.012. Cherubini, F., Jungmeier, G., Welisch, M., Willke, T., Skiadas, I., Van Ree, R., de Jong, E., 2009. Toward a common classification approach for biorefinery systems. Biofuels, Bioprod. Biorefining 3, 534–546. https://doi.org/10.1002/bbb.172. Chhabra, R., Basavaraj, M.G., 2019. Coulson and Richardson’s Chemical Engineering. Volume 2A: Particulate Systems and Particle Technology, sixth. ed. Elsevier. Butterworth-Heinemann, Oxford, UK. https://doi.org/10.1016/B978-0-08-101098-3. 00011-1. de Brujin, H., van Duin, R., Huijbregts, M.A.J., 2004. Handbook on Life Cycle Assesment. Operational Guide to the ISO Standars. Kluwer Academic Publishers, New York. De la Cerda, P.C., 2012. Caracterización Y Aprovechamiento Del Residuo Del Tallado De Agave lechuguilla Torrey (guishe). Universidad Autónoma Agraria Antonio Narro, México. Di Donato, P., Poli, A., Taurisano, V., Nicolaus, B., 2014. Polysaccharides: applications in biology and biotechnology/ polysaccharides from bioagro-waste new biomoleculeslife. Polysaccharides 1–29. https://doi.org/10.1007/978-3-319-03751-6_16-1. Díaz-Blanco, D.I., de La Cruz, J.R., López-Linares, J.C., Morales-Martínez, T.K., Ruiz, E., Rios-González, L.J., Romero, I., Castro, E., 2018. Optimization of dilute acid pretreatment of Agave lechuguilla and ethanol production by co-fermentation with Escherichia coli MM160. Ind. Crops Prod. 114, 154–163. https://doi.org/10.1016/j. indcrop.2018.01.074. Dubois, M., Gilles, K.A., Hamilton, J.K., Rebers, P.A., Smith, F., 1956. Colorimetric method for determination of sugars and related substances. Anal. Chem. 28, 350–356. https://doi.org/10.1021/ac60111a017. Elkhalifa, S., Al-Ansari, T., Mackey, H.R., Mckay, G., 2019. Food waste to biochars through pyrolysis : a review. Resour. Conserv. Recycl. 144, 310–320. https://doi.org/ 10.1016/j.resconrec.2019.01.024. Fedailaine, M., Moussi, K., Khitous, M., Abada, S., Saber, M., Tirichine, N., 2015. Modeling of the anaerobic digestion of organic waste for biogas production. Procedia Comput. Sci. 52, 730–737. https://doi.org/10.1016/j.procs.2015.05.086. Foley, H.C., 2002. Introduction to Chemical Engineering Analysis Using Mathematica. Academic Press, San Diegoa, Cal., USA. Gutiérrez, M.C., Rosas, J.M., Rodríguez-Cano, M.A., López-Luque, I., Rodríguez-Mirasol, J., Cordero, T., 2019. Strategic situation, design and simulation of a biorefinery in Andalusia. Energy Convers. Manage. 182, 201–214. https://doi.org/10.1016/j. enconman.2018.12.038. Hassan, S.S., Williams, G.A., Jaiswal, A.K., 2019. Moving towards the second generation of lignocellulosic biorefineries in the EU: drivers, challenges, and opportunities. Renewable Sustainable Energy Rev. 101, 590–599. https://doi.org/10.1016/j.rser. 2018.11.041. Hernández, R., Lugo, E.C., Díaz, L., Villanueva, S., 2005. Extraction and indirect quantification of saponins from the Agave lechuguilla Torrey. E-Gnosis [online] 3, 1–9. ISO 14040, 2006. Environmental Management – Life Cycle Assessment – Principles and Framework. International Organization of Standardization, Geneva, Switzerland. ISO 14044, 2006. Environmental Management – Life Cycle Assessment – Requirements and Guidelines. International Organization of Standardization, Geneva, Switzerland. James, A.K., Thring, R.W., Helle, S., Ghuman, H.S., 2012. Ash management review-applications of biomass bottom ash. Energies 5, 3856–3873. https://doi.org/10.3390/ en5103856. Jasso de Rodríguez, D., Rodríguez García, R., Hernández Castillo, F., Aguilar González, C.N., Sáenz Galindo, A., Villarreal Quintanilla, J.A., Moreno Zuccolotto, L.E., 2011. In vitro antifungal activity of extracts of Mexican Chihuahuan Desert plants against postharvest fruit fungi. Ind. Crops Prod. 34, 960–966. https://doi.org/10.1016/j. indcrop.2011.03.001. Jiménez Muñoz, E., 2017. Obtención De La Pulpa De Celulosa a Partir De Residuos De Agavaceas: Potencial Elaboración De Papel Tipo Artesanal. Universidad Autónoma del Estado de Hidalgo, México. Juárez, C., Durán, A., Valdez, P., Fajardo, G., 2007. Performance of “Agave lecheguilla” natural fiber in portland cement composites exposed to severe environment conditions. Build. Environ. 42, 1151–1157. https://doi.org/10.1016/j.buildenv.2005.12. 005. Kadam, K.L., Rydholm, E.C., McMillan, J.D., 2004. Development and validation of a kinetic model for enzymatic saccharification of lignocellulosic biomass. Biotechnol. Prog. 20, 698–705. https://doi.org/10.1021/bp034316x. Kalan Kash, S.C., 2009. Estudio Orientado a Identificar Los Mercados Y Canales De

Comercialización Internacionales Para La Oferta De Productos De Ixtle Con Valor Agregado. Liu, Z., Li, Z., Zhong, H., Zeng, G., Liang, Y., Chen, M., Wu, Z., Zhou, Y., Yu, M., Shao, B., 2017. Recent advances in the environmental applications of biosurfactant saponins: a review. J. Environ. Chem. Eng. 5, 6030–6038. https://doi.org/10.1016/j.jece.2017. 11.021. Lupton, R.C., Allwood, J.M., 2017. Hybrid Sankey diagrams: visual analysis of multidimensional data for understanding resource use. Resour. Conserv. Recycl. 124, 141–151. https://doi.org/10.1016/j.resconrec.2017.05.002. Mao, C., Feng, Y., Wang, X., Ren, G., 2015. Review on research achievements of biogas from anaerobic digestion. Renewable Sustainable Energy Rev. 45, 540–555. https:// doi.org/10.1016/j.rser.2015.02.032. Mayorga Hernandez, E., Rossel Kipping, D., Ortiz Laurel, H., 2001. Evaluación funcional de una máquina desfibradora de lechuguilla (Agave lechuguilla Torr). In: Jiménez Regalado, R. (Ed.), XI Congreso Nacional de Ingeniería Agrícola. Asociación Mexicana de Ingeniería Agrícola, pp. 32–38. Mazaheri, N., Akbarzadeh, A.H., Madadian, E., Lefsrud, M., 2019. Systematic review of research guidelines for numerical simulation of biomass gasification for bioenergy production. Energy Convers. Manage. 183, 671–688. https://doi.org/10.1016/j. enconman.2018.12.097. Medellín-Castillo, N.A., Hernández-Ramírez, M.G., Salazar-Rábago, J.J., LabradaDelgado, G.J., Aragón-Piña, A., 2017. Bioadsorción de plomo (II) presente en solución acuosa sobre residuos de fibras naturales procedentes de la industria ixtlera (Agave lechuguilla Torr. Y Yucca carnerosana (Trel.) McKelvey). Rev. Int. Contam. Ambient. 33, 269–280. https://doi.org/10.20937/RICA.2017.33.02.08. Mendez, M., Rodríguez, R., Ruiz, J., Morales-Adame, D., Castillo, F., Hernández-Castillo, F.D., Aguilar, C.N., 2012. Antibacterial activity of plant extracts obtained with alternative organics solvents against food-borne pathogen bacteria. Ind. Crops Prod. 37, 445–450. https://doi.org/10.1016/j.indcrop.2011.07.017. Moghimipour, E., Handali, S., 2015. Saponin: properties, methods of evaluation and applications. Annu. Res. Rev. Biol. 5, 207–220. https://doi.org/10.9734/arrb/2015/ 11674. Morales-Luckie, R.A., Lopezfuentes-Ruiz, A.A., Olea-Mejía, O.F., Argueta Figueroa, L., Sanchez-Mendieta, V., Brostow, W., Hinestroza, J.P., 2016. Synthesis of silver nanoparticles using aqueous extracts of Heterotheca inuloides as reducing agent and natural fibers as templates: agave lechuguilla and silk. Mater. Sci. Eng. C 69, 429–436. https://doi.org/10.1016/j.msec.2016.06.066. Morales-Martínez, T.K., Díaz-Blanco, D.I., Rodríguez-de la Garza, J.A., Morlett-Chávez, J., Castro-Montoya, A.J., Quintero, J., Aroca, G., Rios-González, L.J., 2017. Assessment of different saccharification and fermentation configurations for ethanol production from Agave lechuguilla. BioResources 12, 8093–8105. https://doi.org/10.15376/ biores.12.4.8093-8015. Neiva, D.M., Araújo, S., Gominho, J., de Cássia Carneiro, A., Pereira, H., 2018. Potential of Eucalyptus globulus industrial bark as a biorefinery feedstock: chemical and fuel characterization. Ind. Crops Prod. 123, 262–270. https://doi.org/10.1016/j.indcrop. 2018.06.070. Oliveira, S.C., Oliveira, R.C., Tacin, M.V., Gattás, E.A.L., 2016. Kinetic modeling and optimization of a batch ethanol fermentation process. J. Bioprocess. Biotech. 6, 1–7. https://doi.org/10.4172/2155-9821.1000266. Ortiz-Méndez, O.H., Morales-Martínez, T.K., Rios-González, L.J., Rodríguez-de la Garza, J.A., Quintero, J., Aroca, G., 2017. Bioethanol production from Agave lechuiguilla biomass pretreated by autohydrolysis. Rev. Mex. Ing. Química 16, 467–476. Orzua, M.C., Mussatto, S.I., Contreras-Esquivel, J.C., Rodriguez, R., de la Garza, H., Teixeira, J.A., Aguilar, C.N., 2009. Exploitation of agro industrial wastes as immobilization carrier for solid-state fermentation. Ind. Crops Prod. 30, 24–27. https:// doi.org/10.1016/j.indcrop.2009.02.001. Reyes-Agüero, J.A., Aguirre-Rivera, J.R., Peña-Valdivia, C.B., 2000. Biología y aprovechamiento de Agave lechuguilla Torrey. Boletín la Soc. Botánica México 67, 75–88. https://doi.org/10.17129/botsci.1626. Romero-González, J., Gardea-Torresdey, J.L., Peralta-Videa, J.R., Rodríguez, E., 2005. Determination of equilibrium and kinetic parameters of the adsorption of Cr(III) and Cr(VI) from aqueous solutions to Agave lechuguilla biomass. Bioinorg. Chem. Appl. 3, 55–68. https://doi.org/10.1155/BCA.2005.55. Romero-González, J., Walton, J.C., Peralta-Videa, J.R., Rodríguez, E., Romero, J., GardeaTorresdey, J.L., 2009. Modeling the adsorption of Cr(III) from aqueous solution onto Agave lechuguilla biomass: study of the advective and dispersive transport. J. Hazard. Mater. 161, 360–365. https://doi.org/10.1016/j.jhazmat.2008.03.102. SEMARNAT, 2003. Nom-008-Semarnat-1996. Diario Oficial de la Federación, México. Siller Juarez, D., Flores López, M.L., Sánchez-Robles, J.H., De la Cerda Suárez, P.C., Charles Rodríguez, A.V., Díaz Jiménez, L., 2014. Variability of saponins concentration in guishe collected in different geographical areas and weather conditions. J. Chem. Biochem. 2, 105–115. https://doi.org/10.15640/jcb.v2n2a5. Siller Juárez, D.F., 2012. Extracción Y Purificación De Saponinas Del Residuo Del Tallado Del Agave lechuguilla Torrey (guishe) Y Su Aplicación Potencial. Universidad Autónoma Agraria Antonio Narro, México. Vasco-correa, J., Khanal, S., Manandhar, A., Shah, A., 2018. Bioresource Technology Anaerobic digestion for bioenergy production : global status, environmental and techno-economic implications, and government policies. Bioresour. Technol. 247, 1015–1026. https://doi.org/10.1016/j.biortech.2017.09.004. Velásquez-Martínez, A., Díaz-Díaz, A., Hernández-Escobar, C.A., Zaragoza-Contreras, E.A., 2011. Agave lechuiguilla Torrey fiber as reinforcement polyester resin. Polym. Compos. https://doi.org/10.1002/pc. Verástegui, Á., Verde, J., García, S., Heredia, N., Oranday, A., Rivas, C., 2008. Species of Agave with antimicrobial activity against selected pathogenic bacteria and fungi. World J. Microbiol. Biotechnol. 24, 1249–1252. https://doi.org/10.1007/s11274007-9563-8.

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Industrial Crops & Products 138 (2019) 111441

L. Díaz-Jiménez, et al. Vieira, M.C., Heinze, T., Antonio-Cruz, R., Mendoza-Martinez, A.M., 2002. Cellulose derivatives from cellulosic material isolated from Agave lechuguilla and fourcroydes. Cellulose 9, 203–212. https://doi.org/10.1023/A:1020158128506. Villarreal Sánchez, J.A., 2019. Desarrollo De Un Bioinoculante Prototipo a Partir Del Aprovechamiento De Residuos De Un Proceso De Gasificación. Centro de Investigación y de Estudios Avanzados, México. Wang, Y., Kinoshita, C.M., 1993. Kinetic model of biomass gasification. Sol. Energy 51, 19–25. https://doi.org/10.1016/0038-092X(93)90037-O.

Wennersten, R., 2004. Extraction of organic compounds. In: Rydberg, J., Cox, M., Musikas, C., Choppin, G.R. (Eds.), Solvent Extraction Principles and Practice. Marcel Dekker, Inc., New York, pp. 418–456. Yu, S., Park, Jinje, Kim, M., Ryu, C., Park, Jungkeuk, 2019. Bioresource Technology Reports Characterization of biochar and byproducts from slow pyrolysis of hinoki cypress. Bioresour. Technol. Reports 6, 217–222. https://doi.org/10.1016/j.biteb. 2019.03.009.

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