PREPARATION OF RICE STRAW ACTIVATED CHARCOAL BY 2- STEP H3PO4 ACTIVATION
Objective: To determine optimal conditions required for activated charcoal production from rice straw with high quality for medical and pharmaceutical applications using chemical activation process.
Methods: Effects of different pretreatment protocols in 2-step H3PO4 activation of Thai rice straw on adsorption properties, pore structure, and surface chemistry were investigated. The rice straw was carbonized at 400 Â°C for 2 h. The obtained charcoal was then impregnated with 85% H3PO4 in the ratio of 1:4 w/v for 24 h, followed by carbonization at 500, 600 and 700 Â°C for 1 h.
Results: The results indicated that the 2-step H3PO4 activation, impregnating and carbonization at 700 Â°C was more efficient in producing activated charcoal because of showing the highest iodine adsorption (629 mg/g), methylene blue adsorption (198 mg/g) and Pb2+ions adsorption (64.19%). The adsorption capacity on iodine, methylene blue, and Pb2+ ions were compared. The results showed that rice straw activated charcoal was most efficient highest to adsorb Pb2+ ions. This adsorption capacity was higher than that of the commercial medical-grade activated charcoal.
Conclusion: The rice straw activated charcoal which was prepared by 2-step H3PO4 activation tends to be potential for medical and pharmaceutical applications.
Keywords: Rice straw, Activated charcoal, Phosphoric acid
2. Estrellan CR, Iino F. Toxic emissions from open burning. Chemosphere 2010;80:193-207.
3. Park J, Lee Y, Ryu C, Park YK. Slow pyrolysis of rice straw: analysis of products properties, carbon, and energy yields. Bioresour Technol 2014;155:63-70.
4. Sarnklong C, Cone JW, Pellikaan W, Hendriks WH. Utilization of rice straw and different treatments to improve its feed value for ruminants: a review. Asian-Australas J Anim Sci 2010;23:680-92.
5. El-Hendawy A-NA. Surface and adsorptive properties of carbons prepared from biomass. Appl Surface Sci 2005;252:287-95.
6. Harry Marsh and Francisco Rodriguez-Reinoso. Activated carbon. United Kingdom. Elesevier; 2006.
7. United States Pharmacopeia and National Formulary, Rockville, MD; 2013.
8. Cooney DO. Activated Charcoal in Medical Applications. Marcel Dekker. New York; 1995.
9. Roy GM. Activated carbon applications in the food and pharmaceutical industries. U. S. A. Technomic publishing; 1995.
10. Chang KL, Chen CC, Lin JH, Hsien JF, Wang Y, Zhao F, et al. Rice straw-derived activated carbons for the removal of carbofuran from an aqueous solution. New Carbon Mater 2014;29:47-54.
11. Hsu NH, Wang SL, Liao YH, Huang ST, Tzou YM, Huang YM. Removal of hexavalent chromium from acidic aqueous solutions using rice straw-derived carbon. J Hazard Mater 2009;171:1066-70.
12. American Standard of testing Material. Standard test method for Determination of Iodine Number of Activated Carbon ASTM D; 1995. p. 4607-94.
13. Japanese IND. Standard committee. JIS, K; 1958. p. 1426.
14. Zaman ZC, Hamid SBA, Das R, Hasan MR, Zain SM, Khalid K, et al. Preparation of carbonaceous adsorbents from lignocellulosic biomass and their use in removal of contaminants from aqueous solution. Bioresources 2013; 8:6523-55.
15. Fierro V, Muniz G, Basta AH, El-Saied H, Celzard A. Rice straw as a precursor of activated carbons: Activation with orthophosphoric acid. J Hazard Mater 2010;181:27-34.
16. Boeriu CG, Bravo D, Gosselink RJA, Van Dam JEG. Characterisation of structure-dependent functional properties of lignin with infrared spectroscopy. Ind Crops Prod 2004;20:205-18.
17. Olorundare OF, Msagati TAM, Krause RWM, Okonkwo JO, Mamba BB. Activated carbon from lignocellulosic waste residues: effect of the activating agent on porosity characteristics and use as adsorbents for organic species. Water Air Soil Pollut 2014;225:1-14.
18. Puziy AM, Poddubnaya OI, MartÃnez-Alonso A, SuÃ¡rez-GarcÃa F, TascÃ³n JM. Surface chemistry of phosphorus-containing carbons of lignocellulosic origin. Carbon 2005;43:2857-68.
19. Bansal RC, Goyal M. Activated carbon adsorption: Taylor and Francis Group; 2005.
20. MihajloviÄ‡ MT, LazareviÄ‡ SS, JankoviÄ‡-ÄŒastvan IM, JokiÄ‡ BM, JanaÄ‡koviÄ‡ ÄT, PetroviÄ‡ RD. A comparative study of the removal of lead, cadmium and zinc ions from aqueous solutions by natural and Fe (III)-modified zeolite. Chem Ind Chem Eng Q 2014;20:283-93.
21. Faur-Brasquet C, Reddad Z, Kadirvelu K, Le Cloirec P. Modeling the adsorption of metal ions (Cu2+, Ni2+, Pb2+) onto ACCs using surface complexation models. Appl Surface Sci 2002;196:356-65.