Cui L, Liu C, Wu G
Key Laboratory of Catalysts and Materials Science of Hubei Province, College of Chemical and Material Science, South-central University for Nationalities, Wuhan 430-074, China.
Environ Technol. 2008 Sep;29(9):1021-30. doi: 10.1080/00207210802166872.
Biosorption of Methylene Blue (MB) from aqueous solution using orange peel biosorbent was experimentally investigated. The effects of dye concentration, solution pH, salt concentration and contact time were investigated in a batch model. The results showed that adsorption equilibrium was reached within one hour at two initial MB concentrations (200 and 1000 mg 1(-1)). The uptake of MB was significantly affected by the pH of dye solution. As the pH decreased, the uptake of MB decreased and was zero at pH 2. The Langmuir isotherm model fitted the experimental data well, and the maximum adsorption capacities of the orange peel were 246.8 +/- 10.6 and 370.3 +/- 31.0 mg g(-1) at pH 7 and pH 10, respectively. The uptake of MB was significantly affected by the high concentration of salts. Adsorption of MB onto orange peel was reversible, and the sorption/desorption efficiencies remained almost 100% even up to seven reuse cycles when the biosorbent loss was taken into consideration. The binding sites were identified to be primary carboxyl groups present in orange peel. The main mechanism of MB adsorption is considered to be electrostatic interaction.
采用橙皮生物吸附剂对水溶液中的亚甲基蓝（MB）进行了生物吸附实验研究。在间歇模型中考察了染料浓度、溶液pH值、盐浓度和接触时间的影响。结果表明，在两种初始MB浓度（200和1000 mg L⁻¹）下，1小时内达到吸附平衡。MB的吸附量受染料溶液pH值的显著影响。随着pH值降低，MB的吸附量减少，在pH 2时为零。Langmuir等温线模型能很好地拟合实验数据，橙皮在pH 7和pH 10时的最大吸附容量分别为246.8±10.6和370.3±31.0 mg g⁻¹。高浓度盐对MB的吸附有显著影响。MB在橙皮上的吸附是可逆的，考虑到生物吸附剂的损失，即使在多达7个重复使用周期中，吸附/解吸效率仍几乎保持100%。已确定结合位点为橙皮中存在的伯羧基。MB吸附的主要机制被认为是静电相互作用。
