Iron hydroxyphosphate composites derived from waste lithium-ion batteries for lead adsorption and Fenton-like catalytic degradation of methylene blue

Journal Pre-proof Iron hydroxyphosphate composites derived from waste lithium-ion batteries for lead adsorption and Fenton-like catalytic degradation of methylene blue Lei Xu, Chen Chen, Jiang-Bo Huo, Xiaoxiao Chen, Jia-Cheng E. Yang, Ming-Lai Fu

PII: DOI: Reference:

S2352-1864(19)30286-X https://doi.org/10.1016/j.eti.2019.100504 ETI 100504

To appear in:

Environmental Technology & Innovation

Received date : 25 June 2019 Revised date : 24 September 2019 Accepted date : 10 October 2019 Please cite this article as: L. Xu, C. Chen, J.-B. Huo et al., Iron hydroxyphosphate composites derived from waste lithium-ion batteries for lead adsorption and Fenton-like catalytic degradation of methylene blue. Environmental Technology & Innovation (2019), doi: https://doi.org/10.1016/j.eti.2019.100504. This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.

© 2019 Published by Elsevier B.V.

Journal Pre-proof

Iron hydroxyphosphate composites derived from waste lithium-ion batteries for lead adsorption and Fenton-like catalytic degradation of methylene blue Lei Xu a, b, Chen Chen a, Jiang-Bo Huo a, Xiaoxiao Chen a, Jia-Cheng E. Yang a,

Key Laboratory of Urban Pollutant Conversion, Institute of Urban Environment (IUE),

p ro

a

of

Ming-Lai Fu a, *

Chinese Academy of Sciences, Xiamen 361021, China b

University of Chinese Academy of Sciences, Beijing 100049, China

Pr e-

*Corresponding author. Tel.: +86 592 6190762; fax: +86 592 6190762.

Jo

urn

al

E-mail addresses: [email protected] (M.-L. Fu).

Journal Pre-proof

Iron hydroxyphosphate composites derived from waste lithium-ion batteries for lead adsorption and Fenton-like catalytic degradation of methylene blue

of

Abstract: Lithium iron phosphate (LiFePO4) batteries occupy the largest current Chinese market share of lithium-ion batteries, resulting in a large number of waste LiFePO4 batteries needed to be considered.

p ro

In this paper, iron hydroxyphosphate composites (FPOH) derived from waste LiFePO4 lithium-ion batteries through hydrothermal treatment as environmental functional materials was firstly investigated. It is found that the cathode scraps and aluminum foil can be easily separated, making the recovery of aluminum foil simple. FPOH can be applied to adsorption of heavy metal and degradation of organic

Pr e-

dye. Based on adsorption kinetic, isotherms and analysis of products after adsorption of lead, lead hydroxyphosphate was indicated to be formed and the maximum adsorption capacities of FPOH for Pb(II) was 43.203 mg/g. FPOH can also effectively degrade organic dyes of methylene blue in 12 hours and the degradation mechanism can be suggested as Fenton-like catalysis evident by radical quenching

al

test. This report provides a promising method for recycling waste LiFePO4 batteries for the preparation of functional materials applied in environmental remediation.

urn

Keywords: Spent lithium ion batteries; Lithium iron phosphate; Iron hydroxyphosphate composites; Lead adsorption; Fenton-like catalytic

Jo

1: Introduction

Lithium-ion batteries have been widely applied in the field of electronic and electrical appliances, including notebook computers, mobile phones, electric bicycles and electric vehicles (Kim et al., 2012; Li et al., 2017; Lv et al., 2017). The demand and production of

Journal Pre-proof

lithium ion batteries increased rapidly in recent years (X. Sun et al., 2017). Data of lithium-ion battery total cumulative production in China estimated by National Bureau of Statistics of China was 44.43 billion units during 2010-2017, in which the market share of lithium iron phosphate

of

battery was 69% in 2015 (Wang and Wu, 2017; Zeng and Li, 2013). However, due to the increase of charge-discharge times of lithium batteries, capacity fading will eventually result in

p ro

battery scrapping (Dubarry and Liaw, 2009; Tan et al., 2013). It was estimated that the total amount of waste lithium batteries will reach 25 billion units and have a weight of about 500 kilotons by 2020 in China (Zeng et al., 2012). The massive amount of waste lithium batteries

Pr e-

can be regarded as resource for alleviation of the rapid depletion of strategic metals as well as the potential risk of environmental contaminants.

In this context, the recovery of valuable lithium metals, nickel, cobalt, aluminum, and copper from lithium batteries has attracted widespread attention, and various technologies have been developed to increase the recovery efficiencies of valuable metals and to reduce the risk of solid

al

waste management (Heelan et al., 2016; Z. Sun et al., 2017). Classical recycling technologies can be divided into three categories: pyrometallurgy, hydrometallurgy, and biometallurgy (Bian

urn

et al., 2016; Chen et al., 2016; X. Chen et al., 2015; Li et al., 2016; Xin et al., 2016). Compared with the characteristics of high energy consumption, exhaust dust, complicated operation conditions and low recovery rate of pyrometallurgy, hydrometallurgy has more advantages in

Jo

recovering lithium batteries for its simple process and high recovery rate (Chen et al., 2017; Swain, 2017; Yang et al., 2016). Inorganic acids such as sulphuric acid, phosphoric acid and hydrochloric acid (Chen et al., 2018a; Y. Guo et al., 2016) were widely used to leach metal ions from spent lithium-ion batteries. Recently, some studies had begun to consider natural or

Journal Pre-proof

industrial organic acids such as tartaric acid, citric acid and malic acid (Chen et al., 2019) as leaching acids for its availability and inexpensiveness. Cobalt in cathode materials usually needed to be reduced from trivalent to divalent metal by reductant to promote leaching reaction.

of

Many researches had been done in this area. Inorganic substances such as hydrogen peroxide (Cheng et al., 2019), hydrochloric acid and some reducing organic substances such as sucrose

p ro

(Chen et al., 2018b) were used as reductants to assist in the leaching of cobalt ions. While hydrometallurgy method consumes a large amount of inorganic or organic acids, in which waste acids and by-products may cause secondary environmental pollution risks, and also increase

Pr e-

recovery costs (Jeong et al., 2005). Biological methods dissolve metals using the interaction between microorganisms (including bacteria and fungi) and the surface of waste materials, which is mild, environmentally friendly and suitable for low-grade sources. However, strain screening, domestication and long-term cultivation of bacteria limit the promotion of biological technology in the disposal of spent lithium batteries (Horeh et al., 2016). Consequently, some

al

other technologies by use of organic, ionic liquids, supercritical water and carbon dioxide as extraction solvents have also been introduced for the recycling of used lithium batteries (Bertuol

urn

et al., 2016; Liu and Zhang, 2016; Virolainen et al., 2017; Zeng and Li, 2014). In this aspect, cobalt and lithium can be recovered from lithium cobaltite battery with simultaneously detoxification of polyvinyl chloride by subcritical water oxidation, which developed an

Jo

efficient and environmentally friendly process to recycle waste batteries (Liu and Zhang, 2016). Notably, recent studies have focused on preparation and application of emerging materials from cathode material in the waste battery. It was reported that the metal organic frameworks material can be obtained under hydrothermal reaction conditions by adding organic ligands to

Journal Pre-proof

the leachate, which proposed a new approach of high value-added resource utilization for waste batteries (Perez et al., 2016a, 2016b). Other functional materials, such as CoFe2O4 and Co3O4/LiCoO2, obtained from leaching solution were shown to be able to degrade organic dyes

of

with excellent photocatalytic performance, which suggested a new strategy of preparing environmental functional materials from waste batteries (Moura et al., 2017; Santana et al.,

p ro

2017). In the literature, cathode scraps from waste LiCoO2/LiFePO4 batteries were used in catalytic degradation of methylene blue and methyl orange without additional treatment, of which the methylene blue decolorized completely by LiCoO2 cathode scraps in 8 hours by

Pr e-

hydroxyl radicals in this Fenton-like reactions (Garcia et al., 2017; J. Guo et al., 2016). Polymetallic nanoparticles were prepared by reduction of metal ions in the cathode leaching solution with sodium borohydride, which had good decolorization performance of organic dyes (Nascimento et al., 2018). Another strategy was to obtain new cathode materials by coprecipitation of the leachate and calcination of metal hydroxides (Pegoretti et al., 2019).

al

There were also some studies focused on the use of anode graphite to prepare graphene carbon materials for the degradation of catalytic organic compounds and adsorption applications

urn

(Wang et al., 2018; Zhang et al., 2018, 2016). Therefore, to develop a suitable technology that efficiently prepares environmental functional materials in addition to recycle of value metals from waste lithium batteries will prevent waste and lower the environmental impact to the

Jo

greatest extent. Taking consideration of the advantage of hydrothermal treatment, herein, the waste battery cathode scraps of lithium iron phosphate batteries were firstly treated under the hydrothermal condition and the resulted products were examined and applied in environmental remediation, adsorption of heavy metal and catalytic degradation of organic dye. The suggested

Journal Pre-proof

strategy can be a promising method for synergic recycling waste lithium iron phosphate batteries.

of

2: Material and Methods

p ro

2.1: Materials and reagents

Spent LiFePO4 lithium-ion batteries used in this study were collected from the local waste recovery market. These batteries were completely discharged firstly and dismantled manually

Pr e-

to separate anodes and cathodes. The cathode foils were then cut into small scraps approximately 1 cm*1 cm in dimension for further treatment (Fig. 1). All used reagents were of analytical grade without further purification. Aqua regia (HCl: HNO3 = 3: 1) were used to dissolve cathode scraps for further determination the contents of different elements (Table S1). Contents of different components in lithium ion battery were displayed in Table 1. Lead nitrate,

al

methylene blue (MB), 30 wt.% hydrogen peroxide (H2O2) and anhydrous ethanol (EtOH) were purchased from Aladdin Chemistry Co., Lid. Deionized water all used was obtained from a

Jo

urn

Milli-Q 18.5 MΩ water system (Kertone Water Treatment Co., Ltd, China).

Pr e-

p ro

of

Journal Pre-proof

Fig. 1 Main components of LiFePO4 lithium-ion batteries. Table 1. Contents of different components in lithium ion battery. Component cathode scraps copper foil

Mass content (wt.%) 42.24

10.77

15.88

separator

6.05

enclosure

6.96

electrolyte

18.10

urn

al

graphitic carbon

Jo

2.2: Preparation of iron hydroxyphosphate composites (FPOH) Hydrothermal technology was introduced to peel off LiFePO4 cathode materials (LFP) from waste lithium ion battery cathode scraps. In a typical experiment, 0.5 g of cathode scraps and 40 mL of deionized water were transferred into a 50 mL of Teflon autoclave, which was then

Journal Pre-proof

heated at 180 °C in an electric oven for 5 h. After autoclave was cooled down to room temperature, the solids of cathode scraps and aluminum foil can be easily separated. The powder of products was collected from the autoclave and washed with deionized water for several

of

times. After dried at 60 °C for at least 24 h in an oven and grinded, iron hydroxyphosphate

p ro

composites (FPOH) was obtained.

2.3: Characterizations

The crystal structure and phase composition were identified by an X'Pert ProMPD

Pr e-

diffractometer (X'Pert Pro, PANalytical B.V., Holand, Cu Kα radiation, λ = 0.15406 nm, tube voltage of 40 kV, tube current of 40 mA). Scanning electron microscopy (SEM) images were obtained via a field emission scanning electron microscope (Hitachi S-4800, Japan) equipped with an energy dispersive X-ray spectrometer (EDS, Genesis XM2, EDAX, USA). Fourier transform infrared (FTIR) spectra were obtained with a Thermo Scientific Nicolet iS10

al

spectrophotometer. The ζ-potential of iron hydroxyphosphate composites under different pH were measured with Zeta potential and nano/submicron particle size analyzer (ZetaPALS,

urn

Malvern UK). The pyrolysis characteristic and thermogravimetric (TG) analysis of cathode scraps were performed using a Netzsch TG analyzer (TG 209 F3, Netzsch, Germany). The elemental composition of cathode scraps and metal ion content in solution were calculated by

Jo

ICP-OES (Optima 7000DV, PerkinElmer, USA).

2.4: Lead adsorption

The adsorption capacity of lead by FPOH was evaluated by measuring the time-dependent

Journal Pre-proof

concentrations of Pb(II) and initial concentration of Pb(II) in a batch system. To study the equilibrium adsorption isotherm, 30 mg of FPOH was added into the 2, 3, 5, 7, 10, 15 and 20 mg L−1 of Pb(II) solution (200 mL) at the initial pH of 5.0, respectively. The suspensions were

of

transferred to a shaker with a speed of 250 rpm at 25 °C for 24 h. Then, 5 mL of suspensions were sampled and filtered through a 220 nm syringe filter. For the adsorption kinetics of Pb(II),

p ro

30 mg of FPOH was added in 200 mL of 9.1 mg L−1 Pb(II) solution at initial pH of 5.0, and each 5 mL of the solutions was sampled and filtered at regular intervals. To study the effect of solution pH, 30 mg of FPOH was mixed with 200 mL of 5 mg L−1 Pb(II) solution at different

Pr e-

initial pH from 2.0 to 6.5, and ICP-OES was used to analysis the concentration of lead ions in samples.

2.5: Fenton-like catalytic degradation of methylene blue

Dosage of FPOH (0-1 g L−1), dosage of 30 wt.% H2O2 (0-5 mL), pH (5-9) and methylene blue

al

(100 mL) of initial concentration (10, 20, 50 and 100 mg/L) were used in the batch experimental procedure. To study the catalytic degradation mechanism, different doses of anhydrous ethanol

urn

(0-5 mL) are used as quenchers to examine the effect on degradation rate. All suspensions were transferred to a shaker with a speed of 250 rpm at 25 °C, and 5 mL of suspensions were sampled and filtered through a 220 nm Millipore syringe filter at regular intervals with 0.5 mL of

Jo

methanol added immediately to quench the reaction. The absorbance of organic dye solution was determined at 664 nm wavelength against blanks to identify the residual concentration of methylene blue using UV–vis spectrophotometer (Shimadzu UV3600).

Journal Pre-proof

3: Results and discussion

3.1: Characterization of FPOH

of

PXRD patterns were obtained for waste lithium iron phosphate battery cathode materials and products after hydrothermal reaction to identify the crystal structure and phase composition of

p ro

the samples. From Fig. 2a, all the diffraction peaks of the lithium iron phosphate battery cathode material matched the reference pattern of LiFePO4 (JCPDS No. 01-081-1173), whereas all the peaks in Fig. 2b were mainly indexed to be Fe5(PO4)4(OH)3ꞏ2H2O (JCPDS No. 00-045-1436)

Pr e-

after hydrothermal treatment (Q. Chen et al., 2015; Han et al., 2017; Yu et al., 2014). The results showed that the Fe5(PO4)4(OH)3ꞏ2H2O can be formed from waste lithium iron phosphate batteries cathode materials under hydrothermal treatment. The FT-IR spectra of LFP and FPOH were showed in Fig. 3. As shown in Fig. 3a, the band at 1138 cm-1 and 1099 cm-1 for LFP were assigned to the stretching vibration of PO2 and asymmetric stretching vibration of PO (ν3 PO4bond) of LiFePO4. The ν1 PO4-3 bond of LFP appeared at 958 cm-1, 684 cm-1 and 658 cm-1,

al

3

while ν4 PO4-3 appeared at 577 cm-1, ν2 PO4-3 appeared at 534 cm-1. Moreover, Fig. 3b

urn

demonstrated the existence of the stretching vibration of hydroxyl at 3374 cm-1, the stretching vibration of PO2 at 1081 cm-1 and the ν1 PO4-3 bond 668 cm-1 and 607 cm-1 (Burba and Frech, 2004). That suggested these modes in Fig. 3a are primarily composed of phosphate and the

Jo

increase of hydroxyl group in Fig. 3b after hydrothermal reaction. Fig. 4(a, b) presented SEM images of LFP showing inhomogeneous particles encapsulated with acetylene black and binder, which are similar to the precision reported by others during preparing cathode materials (Kim et al., 2007). After hydrothermal treatment, it can be obviously observed that whisker-like

Journal Pre-proof

structure appeared inside the material in Fig. 4(c, d), which could be the rod-shaped iron hydroxyphosphate (Zhang et al., 2014). In addition, SEM energy dispersive X-ray spectroscopy mapping photographs of resulted material showed the uniform distribution of phosphorus and

of

iron on the surface of the material in Fig. S2 (a, b). Thermogravimetric analysis of LFP and FPOH were shown in the Fig. S3 and Fig. S4, respectively. The similar thermogravimetric

p ro

curves showed that they both have three stages of weightlessness: the first stage is the loss of water at low temperature, the 250 ºC -550 ºC is the mass loss of acetylene black, and the high temperature phase is the loss of the binder (Li et al., 2012). The content of carbon in the material

Pr e-

were about 19.01% and 19.84% for LFP and FPOH, respectively.

It is well known that hydroxyapatite exhibited good adsorption properties for lead ions (Liao et al., 2010). It could react with lead ions in aqueous solution to form lead hydroxyphosphate. The mechanism of removing lead ion was similar with that of iron hydroxyphosphate composites. In addition, Fenton catalytic reaction had been widely used in wastewater treatment. Iron-

al

containing materials catalyzed hydrogen peroxide to produce hydroxyl radicals, which could completely degrade and decolorize organic dye pollutants. Based on the above-mentioned

urn

reasons, the resulted products were further examined and applied in the adsorption of lead ions

Jo

and catalytic degradation of organic dye.

Journal Pre-proof

 

Relative Intensity (a.u.)

c



 







  Fe5(PO4)4(OH)3ꞏ2H2O  Pb10 ( PO4 )6 ( OH )2

 

 





 

a

20

30











40

50



60

70

80

Pr e-

10





p ro

b

of

 LiFePO4

2-Theta (degree)

Fig. 2 (a) PXRD patterns of LFP waste battery cathode material; (b) PXRD patterns of FPOH

al 668 607

urn

684 658 577

c

b

1081 958

3374

1099

Jo

a

4000

534

Transmittance (%)

prepared via hydrothermal treatment; (c) PXRD patterns of FPOH after lead adsorption.

3500

3000

2500

2000

1500 -1

wavenumber (cm )

1000

500

Journal Pre-proof

Fig. 3 (a) FT-IR spectra of LFP waste battery cathode material; (b) FT-IR spectra of FPOH

urn

al

Pr e-

p ro

of

prepared via subcritical water treatment; (c) FT-IR spectra of FPOH after lead adsorption.

Fig. 4 SEM photographs of (a, b) LFP, (c, d) FPOH and (e, f) FPOH after lead adsorption.

Jo

3.2: Adsorption isotherm and kinetics The as-obtained composites after hydrothermal treatment were investigated as adsorbent for the adsorption of lead in aqueous solution. To identify the effect of the initial Pb(II) concentration on the adsorption capacity, the parameters of the adsorption isotherm simulation equation were

Journal Pre-proof

illustrated in Table 2. By comparing the correlation coefficient, Langmuir model (R2 = 0.959) fitted the adsorption data slightly better than Freundlich model (R2 = 0.953), which indicated that the Pb(II) adsorption process by FPOH maybe was the monolayer adsorption, and the

of

maximum Pb(II) adsorption capacities was 43.203 mg/g based on Langmuir model (Zuo et al., 2017).

p ro

Table 2. Modeling parameters of lead adsorption isotherms on FPOH sample (dose of adsorbents, 0.15 g L−1, and initial solution pH 5.0). Langmuir model qe = kL qm Ce /(1 + k2 Ce) kL (L/mg)

43.203

0.658

Pr e-

qm (mg/g)

Freundlich model qe = KF (Ce)1/n

R2

KF

n

R2

0.959

17.736

3.040

0.953

The as-obtained composites were compared with previous researches on the related adsorbents for the adsorption of Pb(II) in Table 3. As shown, the amount of lead adsorbed by ferric oxide

al

and L-cysteine functionalized magnetite were 18.8 and 30.873 mg/g, respectively (Bagbi et al., 2017; Gadde and Laitinen, 1973). Carbon based adsorbents (Li et al., 2002; Sekar et al., 2004)

urn

had relatively low adsorption capacity. In general, the hydroxyl group could increase the adsorption capacity of lead ion on adsorbent (Liao et al., 2010). Particularly, the adsorption capacity of rice husk ash (Feng et al., 2004) without special treatment was the lowest, which

Jo

indirectly indicated that the active groups contributed the most to the adsorption of lead. Table 3. Adsorption capacity of Pb(II) comparison between the FPOH in the present study and adsorbents reported in the literature.

Journal Pre-proof

Initial pH

Capacity (mg/g)

References

rice husk ash carbonate hydroxyapatite activated carbon carbon nanotubes hydrous ferric oxide L-Cysteine-Fe3O4 FPOH

5.0 6.0 4.5 5.0 6.0 6.0 5.0

12.61 94.3 26.50 17.44 30.873 18.8 43.203

(Feng et al., 2004) (Liao et al., 2010) (Sekar et al., 2004) (Li et al., 2002) (Gadde and Laitinen, 1973) (Bagbi et al., 2017) This study

p ro

of

Adsorbent

Effect of contact time on lead adsorption was presented in Fig. 5, which indicated 75% of the adsorption capacity was reached in 4 h and gradually achieved equilibrium after 24 h.

Pr e-

Moreover, the adsorption experimental data (18.899 mg/g) is closer to the capacity (18.490 mg/g) indicated from first-order model. Meanwhile, pseudo-first-order model (R2 = 0.998) fit adsorption data slightly better than pseudo-second-order model (R2 = 0.995) in the inserted table of Fig. 5, which suggested that the adsorption is a typical solid-liquid interface adsorption

Jo

urn

al

process and chemical adsorption process may also occur (Huo et al., 2018).

Journal Pre-proof

20

of

FPOH Pseudo-first-order Pseudo-second-order

10 Initial dosage of absorbent (g/L)

5

0.15

Pseudo-first-order model qt=qe(1-exp(-k1t))

qe(mg/g) k1(min-1) R2

qe(mg/g) k2(mgꞏg-1min-1)

10

15

0.019

20

R2

0.995

25

Pr e-

5

Pseudo-second-order model qt=k2q2et/(1+k2qet)

18.490 0.364 0.998 21.476

0

0

p ro

qe(mg g-1)

15

Time (h)

Fig. 5 Adsorption kinetics of Pb(II) of FPOH: adsorbent dose, 0.15 g L−1; initial Pb(II) concentration, 9.1 mg L−1.

al

3.3: Adsorption mechanism Generally, lead ions could be immobilized in aqueous solution by adsorption and

urn

precipitation/co-precipitation, mainly through forming stable metal-phosphate precipitates (Ashrafi et al., 2015; Ivanets et al., 2016). It was worthwhile to mention that the peak of Pb10(PO4)6(OH)2 (JCPDS No. 01-087-2478) was observed in Fig. 2c after lead adsorption. The

Jo

reaction equation was inferred to be consistent with the role of hydroxyapatite in fixing lead as follows (Ma et al., 1994; Raicevic et al., 2005): Fe5 (PO4 )4 (OH)3 ∙2H2 O(c) + 11 H+ ⟷ 5 Fe3+ + 4 H2 PO4 - + 5 H2 O

(1)

Journal Pre-proof

10 Pb2+ + 6 H2 PO4 - + 2 H2 O ⟷ Pb10 (PO4 )6 OH

2(C)

+ 14 H+

(2)

Iron hydroxyphosphate reacted with hydrogen ions and produced hydrogen phosphate under

of

acidic conditions firstly, then lead ions combined with hydrogen phosphate and fixed as lead hydroxyphosphate eventually. The effect of pH on adsorption efficiency was shown in Fig. S5,

p ro

from which the maximum removal efficiency was up to 78.6% at pH of 4.5, decrease of removal rate appeared with different degrees when the pH is higher than 4.5, but Pb(II) was hardly removed when pH was below 4.0. That may be related to the zeta potential of FPOH (Fig. S6), because it was not conducive to the removal of cations when pH is lower than its isoelectric

point.

3.4: Dye degradation

Pr e-

point (PZC = 4.3), while it may hinder the hydrolysis of FPOH at higher pH than the isoelectric

al

Synthetic composites after hydrothermal treatment were investigated for catalytic degradation of organic dye with hydrogen peroxide. The first order reaction kinetic equation was used to

urn

measure methylene blue degradation (Houas et al., 2001). Fig. 6a showed the effect of addition of FPOH on the decolorization of MB. When only 2 mL of hydrogen peroxide was added without FPOH, almost no effect of degradation of MB could be observed, and the removal efficiency was greatly improved with the increase of iron content. It indicated that iron

Jo

hydroxyphosphate composites accelerate the decolorization reaction of MB in the presence of H2O2. Different dosage of hydrogen peroxide was critical to the degradation rate (Fig. 6b) because when the amount of H2O2 addition was 5 mL, the degradation of the dye could be complete after 12 h, while the addition of 2 mL needs 24 h. At different pH, the rate of reaction

Journal Pre-proof

was approximately the same, showed that the material could be applied in a wide range of pH (Fig. 6c). Despite the small effect of volume dilution, compared with the addition of 1 mL of ethanol, the degradation of organic dyes remained low with adding 5 mL of ethanol to the

of

system (Fig. 6d). It indicated that ethanol which is hydroxyl radical quencher reduced the reaction rate and increasing the amount of ethanol caused the degradation rate of methylene

p ro

blue slow down further. The main reaction mechanism of MB degradation may be speculated as the Fenton-like reaction as follows (Dutta et al., 2001; Sangami and Manu, 2017; Shahwan et al., 2011; Xiao et al., 2001; Zhang et al., 2014):

(3)

Fe(II)POH + H2 O2 ⟶ Fe(III)POH + HO∙

(4)

HOꞏ+ MB ⟶ oxMB + H2 O

(5)

Pr e-

Fe(III)POH + H2 O2 ⟶ Fe(II)POH + HO2 ∙

5

-ln(C/C0)

1 0 6

3

4 3

1

(c)

pH=5 pH=6 pH=7 pH=8 pH=9

4

5

2

0 5

(d)

only FPOH only H2O2 1 mL EtOH 5 mL EtOH FPOH+H2O2

Jo

5

urn

3

(b)

0 mL H2O2 0.5 mL H2O2 1 mL H2O2 2 mL H2O2 5 mL H2O2

al

4

2

(a)

0 g/L FPOH 0.1 g/L FPOH 0.25 g/L FPOH 0.5 g/L FPOH 1 g/L FPOH 1 g/L LFP

4 3 2

2

1

1

0

0 0

6

12

18

24 0

Time (h)

6

12

18

24

Journal Pre-proof

Fig. 6 The effect of addition of FPOH (a), addition of H2O2 (b), pH (c) and addition of EtOH (d) on the decolorization of methylene blue by FPOH. Fig. 7 showed that the catalytic degradation ability of FPOH gradually decreased with the

of

increase of organic dye concentration, the methylene blue of 10 ppm could be completely removed in 24 h, and the removal rate of methylene blue in 20 ppm reached 65% with 5 mL of

p ro

H2O2 and 1 g L-1 of FPOH. The recycled degradation performance in Fig. 8 showed that FPOH could still fully degrade methylene blue (10 ppm) after four cycles and the reaction rate was faster due to the more dispersed particles after recycling (Fig. S8 c, d). Actually, the lithium in

Pr e-

waste battery was also evaluated. The effects of water and phosphoric acid at different concentrations on the leaching efficiency of lithium in lithium iron phosphate were supplemented as Fig. S9 in the Supplementary Information.

al

1.0

0.8

urn

C/C0

0.6

10ppm 20ppm 50ppm 100ppm

0.4

Jo

0.2

0.0

0

6

12

Time (h)

18

24

Journal Pre-proof

Fig. 7 The effect of initial dye concentration on the decolorization of methylene blue by

1.0

2nd cycle

1st cycle

4th cycle

p ro

0.8

3rd cycle

of

FPOH.

C/C0

0.6

0.2

0.0

Pr e-

0.4

0 6 12 18 24 0 6 12 18 24 0 6 12 18 24 0

6 12 18 24

Time (h)

al

Fig. 8 Removal efficiency of methylene blue degradation in different recycles (initial

urn

methylene blue concentration 10 ppm, H2O2 volume 5% (v/v) and FPOH dose 1 g L-1).

4: Conclusions

A novel method of resource recovery from waste lithium iron phosphate battery by

Jo

hydrothermal treatment was proposed in this work, which provided a new perspective for recycling spent lithium iron phosphate batteries to prepare functional materials and deal with environmental problems. Cathode scraps and aluminum foil can be easily separated which making the recycling of aluminum foil very simple. The prepared FPOH can be used to adsorb

Journal Pre-proof

heavy metals in water and the maximum adsorption capacity of Pb(II) was 43.203 mg/g. Moreover it can effectively degrade organic dyes in 12 h with excellent Fenton-like catalytic performance. This method can be very promising for the recovery and reuse of waste lithium

p ro

of

iron phosphate batteries.

Acknowledgements: This work was financially supported by the Strategic Priority Research Program (A) of the Chinese Academy of Sciences (No. XDA23030303), the Key Programs of the Chinese Academy of Sciences (KFZD-SW-315) and the Programs of Institute of Urban Environment, CAS

Pr e-

(IUEQN201503).

References:

Ashrafi, M., Mohamad, S., Yusoff, I., Hamid, F.S., 2015. Immobilization of Pb, Cd, and Zn in

al

a contaminated soil using eggshell and banana stem amendments: metal leachability and a sequential extraction study. Environ. Sci. Pollut. Res. 22, 223–230.

urn

Bagbi, Y., Sarswat, A., Mohan, D., Pandey, A., Solanki, P.R., 2017. Lead and Chromium Adsorption from Water using L-Cysteine Functionalized Magnetite (Fe3O4) Nanoparticles. Sci. Rep. 7, 7672.

Jo

Bertuol, D.A., Machado, C.M., Silva, M.L., Calgaro, C.O., Dotto, G.L., 2016. Recovery of cobalt from spent lithium-ion batteries using supercritical carbon dioxide extraction. Waste Manag. 51, 245–251.

Journal Pre-proof

Bian, D., Sun, Y., Li, S., Tian, Y., Yang, Z., Fan, X., Zhang, W., 2016. A novel process to recycle spent LiFePO4 for synthesizing LiFePO4/C hierarchical microflowers. Electrochim. Acta 190, 134–140.

of

Burba, C.M., Frech, R., 2004. Raman and FTIR Spectroscopic Study of LixFePO4 (0⩽x⩽1).

p ro

J. Electrochem. Soc. 151, A1032–A1038.

Chen, J., Li, Q., Song, J., Song, D., Zhang, L., Shi, X., 2016. Environmentally friendly recycling and effective repairing of cathode powders from spent LiFePO4 batteries.

Pr e-

Green Chem. 18, 2500–2506.

Chen, Q., Wei, C., Zhang, Y., Pang, H., Lu, Q., Gao, F., 2015. Single-Crystalline Hyperbranched Nanostructure of Iron Hydroxyl Phosphate Fe5(PO4)4(OH)3ꞏ2H2O for Highly Selective Capture of Phosphopeptides. Sci. Rep. 4. Chen, X., Cao, L., Kang, D., Li, J., Zhou, T., Ma, H., 2018a. Recovery of valuable metals

al

from mixed types of spent lithium ion batteries. Part II: Selective extraction of lithium. Waste Manag. 80, 198–210.

urn

Chen, X., Guo, C., Ma, H., Li, J., Zhou, T., Cao, L., Kang, D., 2018b. Organic reductants based leaching: A sustainable process for the recovery of valuable metals from spent lithium ion batteries. Waste Manag. 75, 459–468.

Jo

Chen, X., Kang, D., Cao, L., Li, J., Zhou, T., Ma, H., 2019. Separation and recovery of valuable metals from spent lithium ion batteries: simultaneous recovery of Li and Co in a single step. Sep. Purif. Technol. 210, 690–697.

Journal Pre-proof

Chen, X., Luo, C., Zhang, J., Kong, J., Zhou, T., 2015. Sustainable Recovery of Metals from Spent Lithium-Ion Batteries: A Green Process. ACS Sustain. Chem. Eng. 3, 3104–3113. Chen, X., Ma, H., Luo, C., Zhou, T., 2017. Recovery of valuable metals from waste cathode

of

materials of spent lithium-ion batteries using mild phosphoric acid. J. Hazard. Mater.

p ro

326, 77–86.

Cheng, Q., Chirdon, W.M., Lin, M., Mishra, K., Zhou, X., 2019. Characterization, modeling, and optimization of a single-step process for leaching metallic ions from

Hydrometallurgy 185, 1–11.

Pr e-

LiNi1/3Co1/3Mn1/3O2 cathodes for the recycling of spent lithium-ion batteries.

Dubarry, M., Liaw, B.Y., 2009. Identify capacity fading mechanism in a commercial LiFePO4 cell. J. Power Sources 194, 541–549.

Dutta, K., Mukhopadhyay, S., Bhattacharjee, S., Chaudhuri, B., 2001. Chemical oxidation of

al

methylene blue using a Fenton-like reaction. J. Hazard. Mater. 84, 57–71. Feng, Q., Lin, Q., Gong, F., Sugita, S., Shoya, M., 2004. Adsorption of lead and mercury by

urn

rice husk ash. J. Colloid Interface Sci. 278, 1–8. Gadde, R.R., Laitinen, H.A., 1973. Study of the sorption of lead by hydrous ferric oxide. Environ. Lett. 5, 223–235.

Jo

Garcia, E.M., Taroco, H.A., Madeira, A.P.C., Souza, A.G., Silva, R.R.A., Melo, J.O.F., Taroco, C.G., Teixeira, Q.C.P., 2017. Application of Spent Li-Ion Batteries Cathode in Methylene Blue Dye Discoloration. J. Chem. 2017, 1–7.

Journal Pre-proof

Guo, J., Zhang, J., Chen, C., Lan, Y., 2016. Rapid photodegradation of methyl orange by oxalic acid assisted with cathode material of lithium ion batteries LiFePO4. J. Taiwan Inst. Chem. Eng. 62, 187–191.

of

Guo, Y., Li, F., Zhu, H., Li, G., Huang, J., He, W., 2016. Leaching lithium from the anode

p ro

electrode materials of spent lithium-ion batteries by hydrochloric acid (HCl). Waste Manag. 51, 227–233.

Han, C., Zhoumin, Ye, Q., Yao, L., Xu, Z., 2017. Controllable synthesis of sphere- and starlike Fe5(PO4)4(OH)3ꞏ2H2O microcrystals for effective photo-Fenton-like degradation of

Pr e-

rhodamine B. Inorg. Nano-Metal Chem. 47, 806–809.

Heelan, J., Gratz, E., Zheng, Z.F., Wang, Q., Chen, M.Y., Apelian, D., Wang, Y., 2016. Current and Prospective Li-Ion Battery Recycling and Recovery Processes. JOM 68, 2632–2638.

al

Horeh, N.B., Mousavi, S.M., Shojaosadati, S.A., 2016. Bioleaching of valuable metals from spent lithium-ion mobile phone batteries using Aspergillus niger. J. Power Sources 320,

urn

257–266.

Houas, A., Lachheb, H., Ksibi, M., Elaloui, E., Guillard, C., Herrmann, J.-M., 2001. Photocatalytic degradation pathway of methylene blue in water. Appl. Catal. B Environ.

Jo

31, 145–157.

Huo, J.-B., Xu, L., Yang, J.-C.E., Cui, H.-J., Yuan, B., Fu, M.-L., 2018. Magnetic responsive Fe3O4-ZIF-8 core-shell composites for efficient removal of As (III) from water. Colloids Surfaces A Physicochem. Eng. Asp. 539, 59–68.

Journal Pre-proof

Ivanets, A., Kitikova, N., Shashkova, I., Matrunchik, Y., Kul’bitskaya, L., Sillanpää, M., 2016. Non-acidic synthesis of phosphatized dolomite and its sorption behaviour towards Pb2+, Zn2+, Cu2+, Cd2+, Ni2+, Sr2+ and Co2+ ions in multicomponent aqueous solution.

of

Environ. Technol. Innov. 6, 152–164.

p ro

Jeong, J., Kim, M.-S., Kim, B.-S., Kim, S.-K., Kim, W.-B., Lee, J.-C., 2005. Recovery of H2SO4 from waste acid solution by a diffusion dialysis method. J. Hazard. Mater. 124, 230–235.

Kim, J.-K., Choi, J.-W., Cheruvally, G., Kim, J.-U., Ahn, J.-H., Cho, G.-B., Kim, K.-W., Ahn,

Pr e-

H.-J., 2007. A modified mechanical activation synthesis for carbon-coated LiFePO4 cathode in lithium batteries. Mater. Lett. 61, 3822–3825.

Kim, T.H., Park, J.S., Chang, S.K., Choi, S., Ji, H.R., 2012. The Current Move of Lithium Ion Batteries Towards the Next Phase. Adv. Energy Mater. 2, 860–872.

al

Li, J., He, X., Zeng, X., 2017. Designing and examining e-waste recycling process: methodology and case studies. Environ. Technol. 38, 652–660.

urn

Li, J., Wang, G., Xu, Z., 2016. Environmentally-friendly oxygen-free roasting/wet magnetic separation technology for in situ recycling cobalt, lithium carbonate and graphite from spent LiCoO2 /graphite lithium batteries. J. Hazard. Mater. 302, 97–104.

Jo

Li, L., Lu, J., Ren, Y., Zhang, X.X., Chen, R.J., Wu, F., Amine, K., 2012. Ascorbic-acidassisted recovery of cobalt and lithium from spent Li-ion batteries. J. Power Sources 218, 21–27.

Journal Pre-proof

Li, Y.-H., Wang, S., Wei, J., Zhang, X., Xu, C., Luan, Z., Wu, D., Wei, B., 2002. Lead adsorption on carbon nanotubes. Chem. Phys. Lett. 357, 263–266. Liao, D., Zheng, W., Li, X., Yang, Q., Yue, X., Guo, L., Zeng, G., 2010. Removal of lead (II)

of

from aqueous solutions using carbonate hydroxyapatite extracted from eggshell waste. J.

p ro

Hazard. Mater. 177, 126–130.

Liu, K., Zhang, F.S., 2016. Innovative leaching of cobalt and lithium from spent lithium-ion batteries and simultaneous dechlorination of polyvinyl chloride in subcritical water. J.

Pr e-

Hazard. Mater. 316, 19–25.

Lv, W., Wang, Z., Cao, H., Sun, Y., Zhang, Y., Sun, Z., 2017. A Critical Review and Analysis on the Recycling of Spent Lithium-Ion Batteries. ACS Sustain. Chem. Eng. 6, 1504–1521.

Ma, Q.Y., Traina, S.J., Logan, T.J., Ryan, J.A., 1994. Effects of aqueous Al, Cd, Cu, Fe (II),

al

Ni, and Zn on Pb immobilization by hydroxyapatite. Environ. Sci. Technol. 28, 1219– 1228.

urn

Moura, M.N., Barrada, R. V, Almeida, J.R., Moreira, T.F.M., Schettino, M.A., Freitas, J.C.C., Ferreira, S.A.D., Lelis, M.F.F., Freitas, M.B.J.G., 2017. Synthesis, characterization and photocatalytic properties of nanostructured CoFe2O4 recycled from spent Li-ion

Jo

batteries. Chemosphere 182, 339–347. Nascimento, M.A., Cruz, J.C., Rodrigues, G.D., de Oliveira, A.F., Lopes, R.P., 2018. Synthesis of polymetallic nanoparticles from spent lithium-ion batteries and application in the removal of reactive blue 4 dye. J. Clean. Prod. 202, 264–272.

Journal Pre-proof

Pegoretti, V.C.B., Dixini, P.V.M., Magnago, L., Rocha, A.K.S., Lelis, M.F.F., Freitas, M., 2019. High-temperature (HT) LiCoO2 recycled from spent lithium ion batteries as catalyst for oxygen evolution reaction. Mater. Res. Bull. 110, 97–101.

of

Perez, E., Andre, M.-L., Navarro Amador, R., Hyvrard, F., Borrini, J., Carboni, M., Meyer,

p ro

D., 2016a. Recovery of metals from simulant spent lithium-ion battery as

organophosphonate coordination polymers in aqueous media. J. Hazard. Mater. 317, 617–621.

Perez, E., Navarro Amador, R., Carboni, M., Meyer, D., 2016b. In-situ precipitation of

188–191.

Pr e-

Metal–Organic Frameworks from a simulant battery waste solution. Mater. Lett. 167,

Raicevic, S., Kaludjerovic-Radoicic, T., Zouboulis, A.I., 2005. In situ stabilization of toxic metals in polluted soils using phosphates: theoretical prediction and experimental

al

verification. J. Hazard. Mater. 117, 41–53. Sangami, S., Manu, B., 2017. Synthesis of Green Iron Nanoparticles using Laterite and their

urn

application as a Fenton-like catalyst for the degradation of herbicide Ametryn in water. Environ. Technol. Innov. 8, 150–163. Santana, I.L., Moreira, T.F.M., Lelis, M.F.F., Freitas, M., 2017. Photocatalytic properties of

Jo

Co3O4/LiCoO2 recycled from spent lithium-ion batteries using citric acid as leaching agent. Mater. Chem. Phys. 190, 38–44.

Journal Pre-proof

Sekar, M., Sakthi, V., Rengaraj, S., 2004. Kinetics and equilibrium adsorption study of lead (II) onto activated carbon prepared from coconut shell. J. Colloid Interface Sci. 279, 307–313.

of

Shahwan, T., Sirriah, S.A., Nairat, M., Boyacı, E., Eroğlu, A.E., Scott, T.B., Hallam, K.R.,

p ro

2011. Green synthesis of iron nanoparticles and their application as a Fenton-like catalyst for the degradation of aqueous cationic and anionic dyes. Chem. Eng. J. 172, 258–266.

Sun, X., Hao, H., Zhao, F., Liu, Z., 2017. Tracing global lithium flow: A trade-linked material

Pr e-

flow analysis. Resour. Conserv. Recycl. 124, 50–61.

Sun, Z., Cao, H., Xiao, Y., Sietsma, J., Jin, W., Agterhuis, H., Yang, Y., 2017. Toward Sustainability for Recovery of Critical Metals from Electronic Waste: The Hydrochemistry Processes. ACS Sustain. Chem. Eng. 5, 21–40.

al

Swain, B., 2017. Recovery and recycling of lithium: A review. Sep. Purif. Technol. 172, 388– 403.

urn

Tan, L., Zhang, L., Sun, Q., Shen, M., Qu, Q., Zheng, H., 2013. Capacity loss induced by lithium deposition at graphite anode for LiFePO4/graphite cell cycling at different temperatures. Electrochim. Acta 111, 802–808.

Jo

Virolainen, S., Fini, M.F., Laitinen, A., Sainio, T., 2017. Solvent extraction fractionation of Li-ion battery leachate containing Li, Ni, and Co. Sep. Purif. Technol. 179, 274–282. Wang, W., Wu, Y., 2017. An overview of recycling and treatment of spent LiFePO4 batteries in China. Resour. Conserv. Recycl. 127, 233–243.

Journal Pre-proof

Wang, Y., Cao, H., Chen, L., Chen, C., Duan, X., Xie, Y., Song, W., Sun, H., Wang, S., 2018. Tailored synthesis of active reduced graphene oxides from waste graphite: Structural defects and pollutant-dependent reactive radicals in aqueous organics decontamination.

of

Appl. Catal. B Environ. 229, 71–80.

p ro

Xiao, F.-S., Sun, J., Meng, X., Yu, R., Yuan, H., Xu, J., Song, T., Jiang, D., Xu, R., 2001. Synthesis and Structure of Copper Hydroxyphosphate and Its High Catalytic Activity in Hydroxylation of Phenol by H2O2. J. Catal. 199, 273–281.

Xin, Y., Xin, B., Guo, X., Chen, S., Wang, J., Wu, F., 2016. Bioleaching of valuable metals

Pr e-

Li, Co, Ni and Mn from spent electric vehicle Li-ion batteries for the purpose of recovery. J. Clean. Prod. 116, 249–258.

Yang, Y., Huang, G., Xu, S., He, Y., Liu, X., 2016. Thermal treatment process for the recovery of valuable metals from spent lithium-ion batteries. Hydrometallurgy 165, 390–

al

396. Yu, F., Zhang, L., Li, Y., An, Y., Zhu, M., Dai, B., 2014. Mechanism studies of LiFePO4

urn

cathode material: lithiation/delithiation process, electrochemical modification and synthetic reaction. RSC Adv. 4, 54576–54602. Zeng, X., Li, J., 2014. Innovative application of ionic liquid to separate Al and cathode

Jo

materials from spent high-power lithium-ion batteries. J. Hazard. Mater. 271, 50–56. Zeng, X., Li, J., 2013. Implications for the carrying capacity of lithium reserve in China. Resour. Conserv. Recycl. 80, 58–63.

Journal Pre-proof

Zeng, X., Li, J., Ren, Y., 2012. Prediction of various discarded lithium batteries in China. IEEE, pp. 1–4. Zhang, T., Lu, Y., Luo, G., 2014. Synthesis of hierarchical iron hydrogen phosphate crystal as

of

a robust peroxidase mimic for stable H2O2 detection. ACS Appl. Mater. Interfaces 6,

p ro

14433–14438.

Zhang, W., Liu, Z., Xu, C., He, W., Li, G., Huang, J., Zhu, H., 2018. Preparing graphene oxide–copper composite material from spent lithium ion batteries and catalytic

Pr e-

performance analysis. Res. Chem. Intermed. 44, 5075–5089.

Zhang, Y., Guo, X., Wu, F., Yao, Y., Yuan, Y., Bi, X., Luo, X., Shahbazian-Yassar, R., Zhang, C., Amine, K., 2016. Mesocarbon Microbead Carbon-Supported Magnesium Hydroxide Nanoparticles: Turning Spent Li-ion Battery Anode into a Highly Efficient Phosphate Adsorbent for Wastewater Treatment. ACS Appl. Mater. Interfaces 8, 21315–

al

21325. Zuo, W.-Q., Chen, C., Cui, H.-J., Fu, M.-L., 2017. Enhanced removal of Cd (ii) from aqueous

urn

solution using CaCO3 nanoparticle modified sewage sludge biochar. RSC Adv. 7,

Jo

16238–16243.

Journal Pre-proof

Pr e-

p ro

of

Graphical Abstract

Iron hydroxyphosphate composites (FPOH) derived from waste lithium ion batteries for lead

Jo

urn

al

adsorption and Fenton-like catalytic degradation of methylene blue.