农业废弃物香芋柄对含Mn2+废水的吸附

以废弃香芋柄作为新型生物吸附剂，通过静态吸附实验，研究了pH、温度、吸附时间、Mn2+初始浓度等因素对香芋柄吸附Mn2+的影响，分析了吸附过程的热力学、动力学和等温吸附规律. 结果表明，溶液初始pH=4，香芋柄用量6 g/L，30℃下吸附60 min，溶液中Mn2+吸附去除率达90.79%以上，吸附容量高达18.16 mg/g. 应用Langmuir和Freundlich模型描述香芋柄对Mn2+的吸附过程，结果显示Freundlich吸附等温线拟合效果更好. 吸附动力学实验数据符合准二级动力学模型. 计算得到热力学参数DG<0, DH>0, DS>0，表明该吸附过程是自发和吸热的过程.

Batch Adsorption of Mn2+ from Aqueous Solution by Agricultural Waste Biomass Taro Stem

With waste taro stem as novel biosorbent, the effects of pH value, temperature, adsorption time and Mn2+ initial concentration on the biosorption capacity of taro stem for Mn2+ were studied by static adsorption experiment. The unit mass of adsorption process was analyzed in thermodynamics and kinetics and adsorption isotherm. The results showed that removal rate of Mn2+ in wastewater was more then 90.79% and adsorption capacity up to 18.16 mg/g when taro stem usage was 6 mg/L, adsorption time 60 min, initial pH=4 of wastewater and temperature 30℃. Langmuir and Freundlich adsorption models were applied to describe the isotherms and isotherm parameters. The Freundlich isotherm was found to be the better theoretical correlation of experimental data. The kinetic experimental data were properly correlated with the pseudo-second-order kinetic model. Thermodynamic parameters of DG, DH and DS were calculated. Their values showed that the overall adsorption process was endothermic and spontaneous.