Microwave Prepared Straw Activated Carbonand Its Impact On Toluene Adsorption

Our country is agricultural country, the crop straw which has high yield, widedistribution, variety, is the precious resources for peasant life and agriculturaldevelopment for a long time. But now agricultural residue is hard to conduct secondarydevelopment because of its low grade and complex composition in the life andproduction. At the same time, the serious phenomenon of the agricultural wasteappeared, such as stacking, landfill and incineration, because of the lack of policyguidance and investment. So it not only causes waste of resources and serious pollutionof the environment that restricts the development of human beings. At the same time,traditional activated carbon that have single raw materials and high price have complexpreparation process and high energy consumption, so its price is higher.This experiment through the single factor experiment and orthogonal experimentto analyze the effects of activating agent, the quality of impregnation ratio, microwavepower, spark time etc. the properties of activated carbon on the preparation conditions,and obtain the optimal preparation process by specific surface area and pore sizeanalysis. The results show that using zinc chloride as the best preparation technologicalconditions for activating agent: microwave power500W, the quality of impregnationratio1:2, activation time4min of activated carbon prepared has the largest specificsurface area of1230m2/g, preparation conditions of activated carbon surface area ofinfluence extent: micro wave power> activation time> impregnation mass ratio.Through the characterization of self-made straw activated carbon shows: theself-made straw activated carbon with microspore structure, pore rich open, the carbonskeleton is clear; the self-made straw activated carbon contains less oxygen containing functional groups showed that the adsorption is mainly physical adsorption; zincchloride in straw preparation of activated carbon process out of the support also reducecarbon skeleton the activation energy of activation of straw.This experiment studied the self-made activated carbon and commercial activatedcarbon on the properties of toluene adsorption study. Through the change of the bedheight, initial concentration of toluene, the gas linear velocity is studied under differentconditions of adsorption properties. Experiments show that: the adsorption capacity oftoluene by activated carbon increased with the initial concentration, the increase of bedheight, with the gas linear velocity decreases slightly downward trend. The unit area ofstraw activated carbon and activated carbon adsorption of toluene was0.267,0.276mg/m2respectively showed that straw charcoal and commercial activated carbonhave the same adsorption capacity, achieving straw resources and the purpose of usingwaste treat waste.The drawn toluene isotherms were fitted by Langmuir and Freundlich derivedactivated carbon adsorption of toluene belongs to the first class of the curve, Langmuirequation better than the Freundlich equation fitting effect, the correlation coefficient R2reached0.99778, Langmuir equation fit the description toluene straw activated carbonadsorption behavior.