黑碳制备的不同热解温度对其吸附菲的影响

Effects of pyrolytic temperature of phenanthrene on its adsorption to black carbon

在300-700℃热解小麦秸秆24h，提取制备黑碳,测定了黑碳化学组成和BET比表面积，研究了菲在黑碳上的吸附与解吸，测定了菲在黑碳上的最大不可逆吸附量．结果表明，随热解温度升高，黑碳比表面积增大，芳构化程度加深，表面疏水性增强；相应地，黑碳对菲的吸附容量和最大不可逆吸附量增大，吸附与解吸非线性程度和解吸迟滞也变得更显著；Freundlich吸附等温式能较好描述菲在黑碳上的吸附与解吸．

Pyrolyzing wheat straw for 24h in the range of 300-700℃, the chemical composition of black carbon and the BET specific surface areas were determined; the phenanthrene adsorption and desorption on black carbon were studied, and the greatest irreversible adsorption amount on black carbon was measured. The specific surface areas of black carbon increased with enhancement of pyrolytic temperature, aromatization degree deepened and surface hydrophobicity strengthened. Relevantly the adsorption capacity and maximum irreversible adsorption amount of phenanthrene by black carbon increased, the adsorption and desorption nonlinearity degree and the hysteresis of desorption also changed more significantly. The phenanthrene adsorption and desorption on black carbon could be described better by the Freundlich adsorption isothermal type.