Abstract:The objective of this work was to investigate adsorptive characteristic of wheat straw biochar (WSBC) for removal of cadmium ions (Cd2+) from aqueous solution. Batch adsorption experiments were carried out to evaluate the effects of pH value of solution, adsorbent dosage, and co-existing cations on the adsorption of Cd2+ using biochar, and the structural characteristics of biochar were analyzed. The results showed that the biochar contained a large amount of oxygen-containing group on the surface. The adsorption efficiency depended on pH value of solution. The adsorption kinetic data were fitted with pseudo-first-order, pseudo-second-order, Elovich, and intra-particle diffusion models. The pseudo-second-order model provided the best fitting for the adsorption kinetics of Cd2+ onto WSBC. In addition, three isotherm models, Langmuir, Freundlich, and Temkin ones were applied to determine the isotherm parameters of adsorption process. The results indicated that the adsorption isotherm was described well with the Freundlich model. Thermodynamics analysis suggested that Cd2+ adsorption onto WSBC was spontaneous and endothermic process.
马锋锋, 赵保卫, 刁静茹. 小麦秸秆生物炭对水中Cd2+的吸附特性研究[J]. 中国环境科学, 2017, 37(2): 551-559.
MA Feng-feng, ZHAO Bao-wei, DIAO Jing-ru. Adsorptive characteristics of cadmium onto biochar produced from pyrolysis of wheat straw in aqueous solution. CHINA ENVIRONMENTAL SCIENCECE, 2017, 37(2): 551-559.
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