莴苣皮生物材料吸附水溶液中阳离子染料的研究

Removal of cationic dyes from aqueous solution by biosorption on lettuce peel

采用莴苣皮粉剂为生物材料吸附剂对亚甲蓝（MB）、亮甲酚兰（BCB）、中性红（NR）3种阳离子染料进行了吸附研究。考察了吸附剂量、吸附剂粒径、吸附时间、染料浓度及pH值等因素对染料吸附的影响，确定了最佳吸附条件。结果显示，莴苣皮粉剂对3种阳离子染料的去除率均较高，当初始pH值等于或大于4时，用2．0g60～80目的莴苣皮粉剂对浓度为100mg·L^-1的3种阳离子染料处理60min后的去除率都在85％以上；吸附等温线符合Langmuir或Freundlich模式，用Lagergren准一级反应动力学方程对吸附过程进行模拟，拟合良好。上述结果表明，莴苣皮可成为一种很有前途的阳离子染料废水处理生物材料。

The potential feasibility of a low cost biomaterial as sorbent for removal of cationic dyes from aqueous solution was investigated. Particles prepared from lettuce peel had been used for biosorption of three cationic dyes, methylene blue （ MB）, brilliant cresyl blue （BCB） and neutral red （NR）. The effects of various experimental parameters （e. g. sorbent amount, particle size, contact time, initial dye concentration and pH etc. ） were examined and optimal experimental conditions were decided. Three dyes studied could be removed effectively by lettuce peel. For example, above the value of initial pH 4, 2. 0 g sorbent particles in 60 80 mesh was chosen to adsorb 100 mg·L^-1 three cationic dyes, after 60 min biosorption, the percentages of three dyes adsorbed were all exceed 85%. The isothermal data fitted the Langmuir or Freundlich models. The biosorption processes followed the pseudo-first-order rate kinetics. The results indicated that lettuce peel was an attractive candidate for removing cationic dyes from dye wastewater.