synthesis characterization and catalytic activities of activated carbon and silica from bio waste materials

Abstract

Rice husk is one of the major agro- based biomass produced in large quantities in developing countries like India and China. Rice husk has high content of fixed carbon and can be used as a good raw material for the preparation of rice husk ash and activated carbon. The effect of the use of Mono Ethyl Amine (MEA), Di Ethyl Amine (DEA) and Poly Ethylene Imines (PEI) as part of our ongoing effort to improve the modification of the surface on activated carbon to increase the CO2 adsorptions capacities at high temperature. Rice husk Ash was prepared at 600oC temperature under N2 and steam atmosphere from rice husk named as RHNS-6, which was impregnated with MEA, DEA and PEI in 5, 10, 15, 20 and 25 wt. % PEI is a good polymer for gas molecules especially those associated with the CO2 molecule due to the molecule contains many nitrogen atoms to react with CO2. Characterized by BET, FTIR and CO2 adsorptions studies with GC. newline RHA prepared 600oC temperature under nitrogen steam atmosphere from rice husk named as RHNS-6. Preparations of 35wt% Cr/RHA and its characterization by XRD, Surface area, Pore size distribution and TGA. The vapor phase dehydration of alcohols like 1,4-butanediol has been studied over 35wt% Cr/RHA catalysts in the temperature range of 540 565 K. The dehydration of 1, 4-butanediol is only 36% when 35wt% Cr/RHA is implied as a catalyst. Catalytic activity of 35wt% Cr/RHA has also been used for dehydration of 1-phenylethanol in the temperature between of 520-540 K. The dehydration 1-phenylethanol is 95% initially. The material shows moderate activity and selectivity towards the product due to well dispersion of Chromia on the Rice husk ash, small particle size of Chromia and more acidic strength of the catalyst. There is no loss of activity during the time on stream due to high porosity and acidity. A comparative study of activity is carried out along with literature reported catalysts in dehydration over various oxide catalysts. newline RHA have almost above 80% SiO2 prepared by acid leaching method.