Adsorbent preparation from Karanja seed shells

E nvironment A sia Available online at www.tshe.org/EA

The international journal published by the Thai Society of Higher Education Institutes on Environment EnvironmentAsia 5 (special issue) (2013) 151-155

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Effect of operating parameters on the yield of Activated

Carbon prepared from Karanja seed shells

Prof. V.N. Ganvir, Akash Dhobale

Department of Petroleum Refining & Petrochemical Technology, Laxminarayan Institute of Technology, Rashtrasant Tukdoji Maharaj Nagpur University,

Bharat Nagar, Amravati Road, Nagpur- 440033. Email: [email protected], [email protected]

Abstract

Solid waste disposal has become a major problem in vegetable oil mill / refinery. Either it has to be disposed safely or use for the recovery of valuable materials. Karanja oil has medicinal value and widely used in soaps, leather tanning and ‘attar’. Nowadays Karanja oil is used for preparation of biodiesel. Karanja shells remains as waste. Therefore, activated carbon was prepared from Karanja shells which are thrown out as a waste from Karanja oil mill and have no further use after seed removal. A study of the effect of the preparation conditions on the yield of activated carbon prepared from Karanja seed shells was made using H3PO4 as an activating agent. The Karanja shells were washed, dried, digested and carbonized at carbonization temperature varying from 4000C to 6000C with carbonization time varying from 10 min to 30 min and acid concentration varying from 0N to 30N. The effects of carbonization temperatures ranging from 400°C to 600°C and acid concentration ranging from 12N to 20 N with nitrogen purge rate of 5 lit/Hr were studied. Proximate analysis of feed was done. Keywords: Activated carbon, Karanja seed shell, yields of activated carbon.

1. Introduction

In the last few years interest & activity have grown up around the globe to find a substitute of fossil fuel. According to Indian scenario the demand of petroleum product like diesel is increasing day by day hence there is an urgent need to find a solution. Biodiesel has become more attractive because of its environmental benefits and fact that it is made up of renewable resources.

Under Indian condition only non-edible oil can be used as biodiesel which are produced in appreciable quantity and

can be grown in large scale on non-cropped marginal lands and waste lands. Non-edible oils like Jatropha, Karanja and Mahua contain 30% or more oil in their seed, fruit or nut. The Karanja oil has a bitter taste and a disagreeable aroma, thus it is not considered edible. [1][2][3]

In India, the Karanja oil is used as a fuel for cooking and lamps. The Karanja oil is also used as a lubricant, water-paint binder, pesticide, and in soap making and tanning industries. The Karanja oil is known to have value in herbal medicine for the treatment of nausea, rheumatism, as well as human and animal skin

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diseases. It is effective in enhancing the pigmentation of skin affected by Leucoderma. The oil of Pongamia is also used as a substitute for diesel. [4]

The methods used for activated carbon synthesis are physical activation and chemical activation. Furthermore, the temperature range used in chemical activation is lower in comparison to that used in physical activation. Phosphoric acid is selected as the activating agent instead of zinc chloride so as not to aggravate environmental pollution by contamination with zinc compounds. The main objective of this research is to prepare activated carbon from Karanja seed shells. 2. Experimental 2.1. Pre-treatment

Karanja shells were obtained from the vegetable oil mill and the seeds were taken out from the shells. The shells were repeatedly washed with distilled water to remove residues and dried at 60°C for 4 hours to reduce moisture content. The dried shells were crushed with a commercial miller into small pieces. 2.2. Impregnation

Impregnation of Karanja pods were done with (4, 8, 12, 16, 20, 24, 28) N phosphoric acid. 5 gm of sample is impregnated with appropriate volume of phosphoric acid of different concentration. The impregnation process was performed at temperature 30ºC for 24 hours in a Petri dish. The impregnated sample was washed with distilled water till we get 7 pH. The sample was dried in an oven at 1000C for 2 hrs. 2.3. Carbonization

After drying, the samples were

placed in crucibles and into a high temperature furnace for carbonization. The colonization process was carried out in an inert atmosphere using nitrogen gas with nitrogen purge rate of 5 lit/hour for time 10, 15, 20 min. After adjusting the nitrogen flow, the furnace is started. The carbonization temperatures used were 4000C, 4500C, 5000C, 5500C and 600°C. 2.4. Proximate analysis of feed 2.4.1. Determination of moisture content.

1.0g of the dried sample was weighed in a crucible. The crucibles were placed in an oven and dried at 105ºC to constant weight for 1 hour as per (ASTMD-3173). The percentage moisture content (% MC) was computed as follows: Moisture content (%) = [(W2-W3) / (W2-W1)] x 100 Where, W1 = weight of crucible, gm. W2=weight of crucible + sample, gm. W3=weight of crucible + sample after heating, gm. 2.4.2 Determination of volatile matter.

Loss in weight was reported as volatile matter on a percentage basis. The difference in weight due to loss of volatile was taken as the total volatile matter present in the biomass.

Volatile matter (%) = [(W5-W6) / (W5-W1)] x 100. Where, W4 = weight of the crucible + weight of the sample before oven drying, gm. W5=weight of the crucible + weight of the sample before keeping in muffle furnace, gm.



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W6=weight of the crucible + weight of sample after keeping in muffle furnace, gm.

2.4.3. Determination of ash content.

The residual carbon in the crucible is heated without lid in a muffle furnace at 750ºC for half an hour for (ASTMD-3174). Heating, cooling and weighing was repeated, till a constant weight was obtained. The residue was reported as ash on a percentage basis. Ash content, (%) = [(W8-W9) / (W7-W1)] x 100. Where,

W7 = weight of the crucible + weight of the sample before oven drying, gm. W8= weight of the crucible + weight of the sample before keeping in muffle furnace, gm. W9=weight of crucible + weight of the sample after keeping in muffle furnace, gm. Table 1. Proximate analysis of Karanja seed shells Test Karanja seed shell

(%) Volatile content 60 Moisture content 4.5 Ash content 3

3. Results and Discussion 3.1. Effect of concentration of phosphoric acid on the yield of activated carbon

Variance of acid concentration by keeping carbonization time and carbonization temperature constant, taken for 5 different temperatures 4000C, 4500C, 5000C, 5500C and 600°C. Figure 1 shows that the yield increases as the

concentration of H3PO4 impregnating solution increases. It approached an optimum point at 16N of H3PO4 with 75.18 % yield. A further increase in loading H3PO4 led to a decrease in yield for all the temperatures considered.

Figure 1. Effect of concentration of phosphoric acid on the yield of activated carbon. 3.2. Effect of carbonization temperature on activated carbon yield

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Carbonization temperature plays a significant role on the activated carbon yield. As we increase the temperature from 4000C to 6000C by keeping carbonization time and acid concentration constant, it is taken for 3 different acid concentrations. The variation of activated carbon yield with carbonization temperature is shown in fig 2. For all 3 impregnation concentrations, it was found that the yield of activated carbon

decreases with increasing temperature from 4500C onwards. This was due to the loss of most of the volatile matter and loss of phosphate compounds. Under high activation temperature yield decreased tremendously as a considerable amount of phosphate compounds volatised when the carbonization temperature is above 450°C.

Figure 2.Effect of carbonization temperature on the yield of Activated Carbon.

3.3. The effect of carbonization time on activated carbon yield

Variation of carbonization time by keeping carbonization temperature and acid

concentration constant, for three different temperature 4500C, 5000C, 5500C

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Figure 3. Effect of carbonization time on the yield of Activated Carbon.

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As we increase the carbonization time from 10 min and onwards for same temperature the yield of activated carbon decreases with increasing time. The optimum carbonization time for the preparation of the adsorbent was found to be 10 min. 4. Conclusion Karanja seed shells can be used as a precursor in the preparation of activated carbon with good surface area around 344 m2/gm. However, an attempt has been made in this work to study the minimum and optimum carbonization temperature of Karanja seed shell between the ranges of 400-6000C. The optimized conditions (Activation concentration, temperature and time) were all studied. Optimized condition for the preparation of activated carbon is found to be 16N of acid concentration, carbonization temperature

4500C and carbonization time 10 min, as per yield point of view. References 1. Subramanian, K.A., Singal, “Utilization of liquid biofuels in automotive diesel engines, Biomass and Bio energy”, 2005; 29:65-72. 2. Azam A.M., and Nahar N. M., “Prospects and potential of fatty acid methyl esters of some non-traditional seed oil for use as biodiesel in India”. Biomass and Bioenergy.2005; 29:293-302. 3. Tiwari S, Saxena M, Tiwari SK “Mahua oil based resins for the high-temperature curing of fly ash coatings”. Journal of applied polymer Science.2003; 87 (2): 110-120. 4. Ashish S. Saksule, “adsorbents from Karanja seed oil cake and applications”. International Journal of Chemical Engineering and Applied Sciences, ISSN 2278 –1366 Original Article, 2012.

Received 16 November 2013 Accepted 3 December 2013 Correspondence to Mr. Akash Dhobale

Department of Petroleum

Refining & Petrochemical

Technology,

Laxminarayan Institute of

Technology, Nagpur- 440033

E-mail: [email protected]