Physico-chemical speciation of particulates emanating from Karanja biodiesel fuelled automotive engine

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Physico-chemical speciation of particulates emanating from Karanja biodiesel fuelled automotive engine

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Pravesh Chandra Shukla a, Tarun Gupta a, Nitin Kumar Labhsetwar c, Avinash Kumar Agarwal b,⇑

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a

Engine Research Laboratory, Department of Civil Engineering, Indian Institute of Technology Kanpur, Kanpur 208016, India Engine Research Laboratory, Department of Mechanical Engineering, Indian Institute of Technology Kanpur, Kanpur 208016, India c Engine Research Laboratory, National Environmental Engineering Research Institute, Nagpur, India b

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h i g h l i g h t s

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 B20 resulted in lower EC/OC vis-a-vis

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 B20 showed slightly lower particle

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diesel. number concentration.

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 Higher count mean diameter

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 CO and THC reduction efficiencies

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were above 80% at higher loads with DOC.  No significant change in NOx emissions.

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g r a p h i c a l a b s t r a c t

observed at higher engine loads.

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a r t i c l e 3 4 2 4 33 34 35 36 37 38 39 40 41 42 43

i n f o

Article history: Received 12 February 2015 Received in revised form 20 July 2015 Accepted 22 July 2015 Available online xxxx Keywords: Biodiesel Diesel oxidation catalyst Diesel emission control Particle size–number distribution

a b s t r a c t It is essential to reduce emissions from existing old vehicles, in order to preserve the environment. In this study, Karanja oil derived biodiesel generated particulates emanating from a medium-duty transportation diesel engine fitted with a diesel oxidation catalyst (DOC), were characterised. Regulated gaseous emissions, particle number–size number distributions, elemental carbon (EC) and organic carbon (OC) of these particulates were determined under varying engine load conditions in order to assess effectiveness of biodiesel compared to mineral diesel in combination with use of DOC. Particle number–size distribution showed significantly higher concentration of nuclei mode particles for both test fuels. Particle size distribution was observed to be bimodal in nature and in two size ranges: less than 10 nm and 25–250 nm, respectively. This study reports a few important insights into possible use of biodiesel in effectively reducing overall particulate emissions as well as gaseous emissions from automotive diesel engines fitted with DOC. Ó 2015 Elsevier Ltd. All rights reserved.

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1. Introduction

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Diesel engines are popular in transportation and power sector, given their higher thermal efficiency and extended durability. India imports approximately 75% of its petroleum requirements in order

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⇑ Corresponding author. E-mail address: [email protected] (A.K. Agarwal).

to cater to its domestic demand [1]. Major fraction of these petroleum products is used in transport sector and diesel vehicles are the most popular workhorses in transport sector [2]. Therefore, there is a need to search for alternative fuel options available for India to meet its domestic energy demand in a sustainable manner. India and other developing countries have a large fleet of old vehicles still operating on their roads, which normally emit relatively higher emissions compared to newer vehicles. These emissions

http://dx.doi.org/10.1016/j.fuel.2015.07.076 0016-2361/Ó 2015 Elsevier Ltd. All rights reserved.

Please cite this article in press as: Shukla PC et al. Physico-chemical speciation of particulates emanating from Karanja biodiesel fuelled automotive engine. Fuel (2015), http://dx.doi.org/10.1016/j.fuel.2015.07.076

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from older vehicles need to be reduced, in order to meet contemporary emission legislations, using one or the other emission reduction technique/hardware. Biodiesel is an important alternative fuel, which is used in diesel engines. Karanja is an important biodiesel feedstock [3] in context of south-east Asia because these trees can be found in abundance in this part of the world and it has the capability of being easily grown even in barren lands. The seeds from such plants are used for oil extraction, which can be eventually converted into Karanja biodiesel by transesterification process. A large number of experimental studies have been performed for Karanja biodiesel application in diesel engines for evaluating various aspects such as engine performance, engine emission, engine wear [4–10,3]. Dhar and Agarwal [4] performed an extensive wear study for a transportation engine fuelled with Karanja biodiesel and its blends. They observed that the surface texture of cylinder liner of the test engine was in good textural condition, even after 250 h endurance test using Karanja biodiesel blend (B20) [4]. Sahoo and Das [5] performed experiments for a comparative evaluation of Jatropha, Karanja and Polanga biodiesels for their performance and emission characteristics. They reported a slight reduction in power output by using biodiesel blends in comparison to mineral diesel [5]. Dhar and Agarwal [10] investigated the effect of Karanja biodiesel blend on the particulate emissions from a transportation engine. They observed that the peak particle number concentration increased with increasing engine load and B20 was quite effective in reducing particulate number emissions [10]. Although, several studies have been carried out on evaluating performance of diesel engines using biodiesel, detailed investigations on a wide spectrum of exhaust emissions and their control using after-treatment devices are rather scanty. Therefore, it is important to characterise emission reduction performance using Karanja biodiesel as a fuel in prevailing diesel engines, to critically assess feasibility of using biodiesel in the transportation sector. There are several advantages of using biodiesel such as negligible sulphur, higher oxygen content and very low aromatics [11]. Low sulphur content is useful in improving the long-term stability of catalysts used in diesel oxidation catalyst (DOC) [12]. DOC is highly effective in removing the soluble organic fraction (SOF) of the diesel particulate matter (DPM), which is considered to be primarily responsible for carcinogenic and mutagenic effects on humans [13,14]. Zielinska et al. [15] observed that the composition of exhaust particulate depends on engine load, and reported mainly organic carbon (OC) emissions at lower engine loads. At lower loads, ultra-fine particles mainly consist of OC and its fraction decreased with increase in particle size. Elemental carbon (EC) becomes a major constituent of diesel particulate matter at higher engine loads. Kweon et al. [16] investigated the effect of engine operating condition on organic compounds in particle phase in a heavy-duty diesel engine. Higgins et al. [17] reported that the particle size in the exhaust decreased with increasing exhaust gas temperature, which was a consequence of increasing engine load. There were studies conducted in the past, where oxidation kinetics of soot was investigated. Schauer et al. [18] reported that, OC was 35% lesser in case of denuder/filter/PUF sampling technique compared to using simple particulate collection on a filter paper, however the total EC remained the same in both the cases. This indicates that the sorption of volatile organic compounds (VOCs) adversely affects the conventional particulate filter collection technique. Kawano et al. [19] and Zhang et al. [20] have investigated the emission characteristics of a diesel engine fuelled with biodiesel and diesel/methanol blends, respectively. Several studies have attempted to characterise different emissions for CI engines fuelled with biodiesel or alcohols blended with diesel or in pure form [21–23].

An exhaustive review of literature on emission control from biodiesel fuelled engine was carried out. It emerges that there is a need for detailed investigations in order to understand the behaviour/characteristics of particulates from a Karanja biodiesel fuelled engine and their impact on a DOC performance vis-a-vis mineral diesel. In the present study, a CI engine fuelled with diesel and Karanja biodiesel blend (B20) is evaluated for their emission characteristics, especially particulates using online emission measurement systems. The performance of DOC with B20 compared to baseline mineral diesel was also evaluated, in order to get a real world impact of the new fuel on the exhaust gas after-treatment technology’s effectiveness. EC/OC and particle number–size distribution were measured and compared for diesel and B20, since these emissions are of prime importance from environmental stand-point.

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2. Experimental setup and methodology

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Karanja biodiesel was prepared using transesterification process in the laboratory using Karanja straight vegetable oil procured from domestic market. Table 1 represents the measured properties of diesel and B20 used in this study. An indirect injection diesel engine (Tata Motors; Indica 475 IDI) was used for comparative study on exhaust emissions for diesel and B20. The engine was retrofitted with a commercial DOC. The DOC (BASF) used in the study was purchased from an open market. This naturally aspirated engine used in the investigations is a popular transport engine, typically used in a mid-size car, which represent the largest selling vehicle segment in India. Table 2 shows specifications of the test engine. Test engine was equipped with a distributor fuel pump with electrical start-stop solenoid, which facilitates fuel injection. Engine was having an exhaust gas recirculation (EGR) system, which reduces NOx emission. Fig. 1 shows the schematic of the experimental setup. The engine was coupled with an eddy current dynamometer (Dynalec Controls; EC-200), which was used for loading and unloading the engine. Dynamometer was controlled by a dynamometer controller. Table 3 shows the specifications of the dynamometer. A partial flow dilution tunnel was employed for diluting the exhaust gas. Dilution of the exhaust gas with ambient air was carried out in order to simulate the actual atmospheric dilution conditions, when exhaust was emitted. A fraction of exhaust gas was diluted by pre-conditioned and pre-filtered air at 52 °C with a fixed dilution ratio of 16. Design and working of the dilution

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Table 1 Properties of Karanja biodiesel vis-a-vis mineral diesel [4]. Property

ASTM 6571 limits for biodiesel

Karanja biodiesel (B100)

Diesel

Density (g/cm3) @ 30 °C Viscosity (cSt) @ 40 °C Flash point (°C) (min.) Cetane number (min.) Conradson carbon residue (%) (max.) Ash content (%) (max.) Moisture content (ppm) (max.) Calorific value (MJ/kg) Copper corrosiveness Iodine value C (%) H (%) N (ppm) O (%) S (ppm) (max.)

0.8–0.9 1.9–6.0 130 47 0.05

0.881 4.41 168 50.8 0.02

0.831 2.78 49.5 51.2 0.01

0.02 500

0.008 <200

0.005 <200

– 3a – – – – – 15

37.98 1a 83 74.2 12.9 3.9 12.8 2

43.78 1a – 87 13 9 0.6 50

Please cite this article in press as: Shukla PC et al. Physico-chemical speciation of particulates emanating from Karanja biodiesel fuelled automotive engine. Fuel (2015), http://dx.doi.org/10.1016/j.fuel.2015.07.076

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Tata Motors/Indica 475 IDI Water cooled indirect injection diesel engine 4 cylinders, inline 75 mm/79.5 mm 1405 cc 39 kW @ 5000 rpm 85 N m @ 2500 rpm 22:1 1-3-4-2 Rotary type with electrical start-stop solenoid

tunnel has been explained in a previous publication from our group by Dwivedi et al. [24]. Dilution ratio was calculated by using the following formula:

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Dilution ratio ‘r’ ¼

½Undiluted Exhaust CO2  ½Diluted Exhaust CO2  Ambient Air CO2 

Raw exhaust emission analyser (Horiba; EXSA-1500) was utilised for real time measurement of carbon monoxide (CO), carbon dioxide (CO2), total hydrocarbons (THC), oxides of nitrogen (NOX) and oxygen (O2) in the exhaust gas. Engine exhaust particle sizer (EEPS) spectrometer (TSI; 3090) was used for online measurement of particle size–number distribution. EEPS measures the particle size and their number concentrations in various size ranges starting from 5.6 nm to 560 nm, with particle density of #108 particles/cc of the exhaust at 10 Hz sampling rate. Since diesel engine exhaust has a very high number density of particles, which could reach up to #1011 particles/cc of exhaust, it needs to be diluted. A fraction of engine exhaust was drawn from the exhaust pipe and diluted using a rotating disc thermo-diluter (Matter Engineering; 379020) in order to lower the particle concentration and bring it down within the measurement range of the EEPS. Thermo-diluter is a device in which exhaust is diluted using filtered sheath air kept at a certain temperature with a fixed dilution ratio. This diluted exhaust stream then enters the EEPS for nano-particle size–number distribution measurement. The dilution ratio of thermo-diluter can be set in the range of 15–3000. This prohibits high particle loading in the instrument and increases its useful working life. OC/EC semi-continuous analyser (Sunset Laboratory; Semi-continuous field v.4) was used for the measurements of OC and EC components of diesel particulates. It provides time-resolved semi-continuous OC/EC concentrations in the particulates by auto-collection of particulate samples on a quartz filter paper, over a fixed time period (Gangwar et al., 2011).

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2.1. Experimental procedure

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The engine was operated at a rated speed of 2500 rpm at five different loads (0%, 25%, 50%, 75% and 100% rated loads) and was fuelled with mineral diesel and B20. For the exhaust gas measurements, sample was drawn and taken to the raw exhaust gas emission analyser (Horiba; EXSA 1500) using an insulated and heated pipe, which maintained the exhaust gas sample at 191 °C in order to avoid condensation of high boiling point hydrocarbons. Another fraction of the exhaust gas was diverted to the exhaust thermo-diluter, which was subsequently supplied to the EEPS for determination of particulate number–size distribution. For EC/OC analysis a fraction of exhaust gas was diluted with pre-conditioned, filtered air in a dilution tunnel, which was maintained at 52 °C. The gaseous emissions were measured 10 times and average readings with error bars have been reported in this study. EC/OC analyser operates with a ±5% standard deviation, which has been shown as error bars in all the related figures. EEPS measurements were taken for 1 min at 1 Hz frequency and an average of these 60 readings was used for plotting the curves.

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3. Results and discussion

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3.1. Particle number–size distribution and particle mass distribution

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Fig. 2 represents the particle size–number distribution for diesel and B20 for various engine loads. Peak particle number concentrations were slightly higher for diesel exhaust compared to B20 exhaust, with DOC except at no load and 25% load (Fig. 2(a)). The particles were observed to be mainly in two distinct size ranges; particles with size less than 20 nm and particles with size ranging between 20 and 250 nm (Fig. 2(a)). Peak of particle size–mass distribution was found to be shifted towards right compared to peak of particle size–number distribution, indicating greater contribution to mass by bigger size particles, which were actually in smaller numbers. Upon comparing particle size–mass distribution (Fig. 2(b)) with the particle size–number distribution (Fig. 2(a)), it is clear that nano-particle emissions are quite high but their contribution to the overall mass is rather negligible. Particle size–mass distribution was calculated from particle size–number distribution by assuming an average particle density as 1 g/cm3. EEPS measures the electron mobility diameter of the particles emitted by the engine.

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Fig. 1. Schematic of the experimental setup.

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Table 3 Dynamometer specifications. Make/model Max. torque Max. power Cooling Max excitation current

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Dynalec controls, ECB-200 420 N m @ 1500–3500 rpm 200 hp @ 3500–8000 rpm Water-cooled 6 A DC

As far as effectiveness of the DOC is concerned, significant reduction was observed in the concentration of particle numbers (Fig. 2(a)). DOCs perform well in oxidising the organic fraction of particulates. Agarwal et al. [25] explained that the major fraction of ultrafine particles comprises of organic species. Possibly the chemical kinetics and close contact of these particles with DOC catalyst present on the surface leads to their significant oxidation.

3.2. Total particle numbers and count mean diameter (CMD)

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Fig. 3(a) shows total particle number concentration for diesel and B20 exhaust, with and without DOC. In general, total particle numbers emitted in the engine exhaust increase with increasing engine load. B20 exhaust showed almost similar (except no load and 25% load) total particle number concentration compared to diesel exhaust. Use of DOC showed reduction in total particle number emissions at all engine operating conditions. For the comparison of mean particle diameter emitted by the engine, with and without DOC, from diesel and B20, count mean diameter (CMD) was calculated. Following equation was used for calculating CMD for each engine operating condition;

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n1 d1 þ n2 d2 þ n3 d3 þ    . . . þ nn dn CMD ¼ n1 þ n2 þ n3 þ . . . . . . þ nn

Fig. 2. Particle size–number distribution and particle size–mass distribution for diesel and B20, with and without DOC.

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Fig. 3. (a) Total particle number concentration (#/cm3) for diesel and B20, with and without DOC (b and c) total particle number with respect to CMD, diesel and B20.

276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292

293 294 295 296 297 298 299

where ni is the total particle number concentration for a particle diameter range with mean diameter di. CMD provides valuable information about the average particle size for a particular engine operating condition. It is important to evaluate the relationship between the total particle number concentration and CMD for a particular engine operating condition. It is undesirable to have higher number of particles having smaller sizes, which makes it easier for them to penetrate deeper into human lungs. Diesel nano-particles have been designated as ‘‘carcinogenic’’ by World Health Organisation (WHO). Particles with lower CMD are more prone to penetrate the human respiratory system with greater probability as compared to the ones with larger CMD. Fig. 3(b) and (c) shows total particle number with respect to corresponding CMD. CMD increased at higher engine loads, which indicates higher fraction of larger particles. For tested engine operating conditions, CMD varied between 39 and 76 nm for diesel and B20, with and without DOC.

3.3. Elemental carbon and organic carbon (EC/OC) contents Fig. 4 shows the emission of EC/OC of the particles in the engine exhaust, with and without DOC for diesel and B20. EC and OC are the main constituents of the particulates. The fractions of EC and OC in particulates mainly depend on the engine operating condition. OC of the particulate is the fraction, which is considered responsible for its hazardous health effects.

Fig. 4. EC/OC of particulates from mineral diesel and B20, with and without DOC. Please note that the ordinates have different scales. EC/OC analyser operates with ±5% standard deviation. (a) Elemental carbon, (b) organic carbon, (c) total carbon and (d) exhaust gas temperature.

3.3.1. Effect of biodiesel Fig. 4 shows the EC of diesel and B20 particulates. As engine load increases, EC also increased for diesel and B20. B20 resulted in significant reduction in EC of the particulates (Fig. 4(a)). In addition, a minor reduction was observed in OC emissions for B20 (Fig. 4(b)). This indicated that although biodiesel significantly reduced the total carbon (TC) emissions, toxic part of the particulates i.e. OC didn’t reduce significantly. Since significant amount of OC is still present in the biodiesel exhaust, it has potential to cause nearly the same adverse health and environmental effects as that of diesel exhaust. Agarwal et al. [25] reported that OC emitted in biodiesel exhaust may be more hazardous and difficult to oxidise as compared to the OC emitted in the diesel exhaust. Overall, TC showed a significant reduction when B20 was used.

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3.3.2. Effect of DOC DOCs are well known for their excellent potential to oxidise the OC fraction of particulates. Fig. 4(b) shows no significant EC reduction at lower engine loads. However, there is some EC reduction

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observed at higher engine loads for both diesel as well as B20. EC is mainly elemental carbon and it has ignition temperature of 600 °C. Therefore, it is difficult to oxidise EC at lower and intermediate diesel engine operating conditions because it hardly reaches these temperature levels in diesel engines. However, some locally high temperature regions, partial trapping of particulates in the sampling line and dilution tunnel may lead to slight reduction of EC in exhaust downstream of DOC. As far as OC is concerned, almost no change was observed for lower loads (no load and 25% load). These observations are in agreement with the ones reported by Cheung et al. [26]. DOC was quite effective in removing the soluble organic fraction (SOF) of the particulates. Notably, most of the OC gets oxidised at intermediate and higher engine loads, when relatively hotter exhaust passes through DOC. Slight difference was observed in the TC reduction for the DOC at lower engine loads. As soon as engine load increased to 50%, exhaust temperature reached a level high enough to oxidise the OC of the particulates. Higher exhaust gas temperature was favourable for superior performance of DOC which leads to the oxidation of OC compounds in presence of catalyst coated on DOC. It is known that the catalysts need a certain light-off temperature to reach its activation energy. Once they attain the required activation energy, they promote reactions for the oxidation of OC. Most of the toxic compounds are part of OC, therefore higher EC/OC ratio is desirable for a given TC from health impact perspective [27].

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3.4. Effectiveness of DOC for CO, THC and NOx reduction

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CO and THC conversion efficiency of DOC was negligible at lower engine loads and higher reductions were achieved at higher loads for B20 (Fig. 5(a) and (b)). Exhaust gas temperature was 115– 120 °C at no load which increased up to 400 °C for the rated load. It is obvious that DOC demonstrates a significantly higher CO and THC conversion at higher exhaust temperature achieved at higher engine load because the catalytic activity of DOC catalyst is a critical function of temperature. Fuel-borne oxygen in B20 leads to more efficient combustion, leading to lower CO and THC emissions.

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Fig. 5. CO, THC and NOx emission for diesel and biodiesel (B20), with and without DOC.

Fig. 6. Reduction in CO and THC due to combined effect of B20 and DOC.

A slight reduction in NOx emission was observed with DOC for both test fuels (diesel and B20) (Fig. 4(c)). As far as test fuels are concerned, NOx emissions were almost same for diesel and B20. DOC was not effective in reducing the CO and THC at no load and low load conditions, due to its ineffectiveness at lower exhaust gas temperatures (Fig. 6(b) and (c)). At intermediate and higher loads, the CO and THC emission reduction efficiency reached up to 90% and 80%, respectively.

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4. Conclusions

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Engine exhaust was analysed for EC/OC, regulated gaseous emissions and particle number–size distribution for mineral diesel and biodiesel blend (B20) fuelled medium duty transportation engine. Following conclusions can be drawn from the experimental observations:

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1. OC of particulates showed different trend and reached a maxima near high loads for both the test fuels. Significant OC reduction was the main reason for reduction in TC at the intermediate and higher loads. 2. Particle size–number distribution showed significant concentration of nuclei mode particles in both, diesel and B20 exhaust, with slightly lower concentration for diesel. However, accumulation mode particles were slightly higher in number in diesel exhaust compared to B20 at higher engine loads. Comparison of particle size–number distribution and particle size–mass distribution showed very low mass contribution from very high number of nuclei mode particles. 3. Total particle numbers were observed to be the highest for diesel exhaust without DOC, at higher engine loads. Combined use of B20 and DOC reduced the total particle numbers significantly, showing considerable benefits in terms of reducing their adverse human health and environmental impacts.

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4. Count mean diameters (CMD) shifted towards the larger particles at higher engine loads, which are relatively less harmful from the human health perspective since the overall particle surface-to-volume ratios were lower.

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This study demonstrated a significant reduction in the overall particulate emissions (in terms of EC/OC and TC) as well as total particle numbers by using B20 in combination of a retrofitted commercial DOC. A large number of studies have already demonstrated compatibility of current diesel engines with B20, it is important to ensure its suitability for exhaust emission stand point as well. This study suggests that the use of biodiesel in combination with the use of DOC for a typical old car, without any significant modifications leads to a significant emission benefits. This also suggests an excellent potential for immediate application of Karanja based biodiesel blend (B20) in the transport sector.

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Acknowledgements

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Authors would like to acknowledge the research grant from Science and Engineering Research Board (SERB), Department of Science and Technology (DST), Government of India (Grant No. SR/S3/MERC-0084/2011 dated 22 June 2012) for carrying out this study. Council of Scientific and Industrial Research (CSIR), Delhi supported Senior Research Associateship (Pool Scientist) to Mr. Pravesh Chandra Shukla. Authors would also like to acknowledge Mr. Roshan Lal of Engine Research Laboratory (ERL; www.iitk.ac. in/erl) for his valuable technical support during this experimental study.

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References

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[1] Indian Petroleum and Natural Gas Statistics, 2013–14. Government of India, Ministry of petroleum & natural gas. Economics and statistics division. New Delhi. [2] Pandey A, Venkataraman C. Estimating emissions from the Indian transport sector with on-road fleet composition and traffic volume. Atmos Environ 2014;98:123–33. [3] Agarwal AK, Khurana D. Long-term storage oxidation stability of Karanja biodiesel with the use of antioxidants. Fuel Process Technol 2013;106:447–52. [4] Dhar A, Agarwal AK. Effect of Karanja biodiesel blend on engine wear in a diesel engine. Fuel 2014;134:81–9. [5] Sahoo PK, Das LM. Combustion analysis of Jatropha, Karanja and Polanga based biodiesel as fuel in a diesel engine. Fuel 2009;88:994–9. [6] Sahoo PK, Das LM, Babu MKG, Arora P, Singh VP, Kumar NR, et al. Comparative evaluation of performance and emission characteristics of jatropha, Karanja and Polanga based biodiesel as fuel in a tractor engine. Fuel 2009;88:1698–707. [7] Dhar A, Agarwal AK. Performance, emissions and combustion characteristics of Karanja biodiesel in a transportation engine. Fuel 2014;119:70–80.

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[8] Dhar A, Agarwal AK. Experimental investigations of effect of Karanja biodiesel on tribological properties of lubricating oil in a compression ignition engine. Fuel 2014;130:112–9. [9] Rathore V, Tyagi S, Newalkar B, Badoni RP. Jatropha and Karanja oil derived DMC–biodiesel synthesis: a kinetics study. Fuel 2015;140:597–608. [10] Dhar A, Agarwal AK. Effect of Karanja biodiesel blends on particulate emissions from a transportation engine. Fuel 2015;141:154–63. [11] Jung H, Kittelson DB, Zachariah MR. Characteristics of SME biodiesel-fueled diesel particle emissions and the kinetics of oxidation. Environ Sci Technol 2006;40:4949–55. [12] Heck RM, Farrauto RJ, Gulati ST. Catalytic air pollution control: commercial technology. John Wiley & Sons; 2012. [13] Westphal GA, Krahl J, Munack A, Ruschel Y, Schroder O, Hallier E, et al. Mutagenicity of diesel engine exhaust is eliminated in the gas phase by an oxidation catalyst but only slightly reduced in the particle phase. Environ Sci Technol 2012;46:6417–24. [14] Eastwood P. Particulate emissions from vehicles. John Wiley & Sons; 2008. [15] Zielinska B, Goliff W, McDaniel M, Cahill T, Kittelson D, Watts W. Chemical analyses of collected diesel particulate matter samples in the E-43 project. Ann Arbor (MI): National Renewable Energy Laboratory; 2003. [16] Kweon C-B, Okada S, FOSTER DE, Bae M-S, Schauer JJ. Effect of engine operating conditions on particle-phase organic compounds in engine exhaust of a heavyduty direct-injection (DI) diesel engine. SAE Trans 2003;112:460–76. [17] Higgins KJ, Jung H, Kittelson DB, Roberts JT, Zachariah MR. Kinetics of diesel nanoparticle oxidation. Environ Sci Technol 2003;37:1949–54. [18] Schauer JJ, Kleeman MJ, Cass GR, Simoneit BR. Measurement of emissions from air pollution sources. 2. C1 through C30 organic compounds from medium duty diesel trucks. Environ Sci Technol 1999;33:1578–87. [19] Kawano D, Ishii H, Goto Y, Noda A. Application of biodiesel fuel to modern diesel engine. SAE technical paper; 2006. [20] Zhang Z, Cheung C, Chan T, Yao C. Experimental investigation on regulated and unregulated emissions of a diesel/methanol compound combustion engine with and without diesel oxidation catalyst. Sci Total Environ 2010;408:865–72. [21] Mirzajanzadeh M, Tabatabaei M, Ardjmand M, Rashidi A, Ghobadian B, Barkhi M, et al. A novel soluble nano-catalysts in diesel–biodiesel fuel blends to improve diesel engines performance and reduce exhaust emissions. Fuel 2015;139:374–82. [22] Yilmaz N, Vigil FM, Benalil K, Davis SM, Calva A. Effect of biodiesel–butanol fuel blends on emissions and performance characteristics of a diesel engine. Fuel 2014;135:46–50. [23] Lahane S, Subramanian KA. Effect of different percentages of biodiesel–diesel blends on injection, spray, combustion, performance, and emission characteristics of a diesel engine. Fuel 2015;139:537–45. [24] Dwivedi D, Agarwal AK, Sharma M. Particulate emission characterization of a biodiesel vs diesel-fuelled compression ignition transport engine: a comparative study. Atmos Environ 2006;40:5586–95. [25] Agarwal AK, Gupta T, Dixit N, Shukla PC. Assessment of toxic potential of primary and secondary particulates/aerosols from biodiesel vis-a-vis mineral diesel fuelled engine. Inhalation Toxicol 2013;25:325–32. [26] Cheung C, Di Y, Huang Z. Experimental investigation of regulated and unregulated emissions from a diesel engine fueled with ultralow-sulfur diesel fuel blended with ethanol and dodecanol. Atmos Environ 2008;42:8843–51. [27] Diaz EA, Chung Y, Papapostolou V, Lawrence J, Long MS, Hatakeyama V, et al. Effects of fresh and aged vehicular exhaust emissions on breathing pattern and cellular responses-pilot single vehicle study. Inhalation Toxicol 2012;24:288–95.

Please cite this article in press as: Shukla PC et al. Physico-chemical speciation of particulates emanating from Karanja biodiesel fuelled automotive engine. Fuel (2015), http://dx.doi.org/10.1016/j.fuel.2015.07.076

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