合成纳米锰钾矿去除废水中Cd2+的实验研究

利用合成纳米锰钾矿去除模拟废水中Cd(Ⅱ),研究不同去除反应条件对废水中镉离子去除率的影响.结果表明:合成纳米锰钾矿对水溶液中Cd2+的去除平衡时间约为2h;在Cd2+质量浓度为50mg·L-1、溶液初始pH=6.50、反应温度25℃、处理剂粒径96～120μm、每升模拟废水中投加2g合成纳米锰钾矿时,平衡后Cd2+去除率为90.6%.当Cd2+质量浓度不高于300 mg·L-1时,吸附等温线近似符合Langmuir模型,合成纳米锰钾矿最大理论吸附量为120.5mg·g-1.纳米锰钾矿对于Cd2+的去除是表面配位吸附、静电吸附、离子交换三种模式共同作用的结果.

Removal of Cd2+ by Synthetic nano-Cryptomelane from Sewage

Removal rates of Cd(Ⅱ) from sewage prepared in laboratory by synthetic nano-cryptomelane under several factors were measured,and the influence of different factors on the rates was studied.Results show that it takes 2 hours for the removal process to reach balance.When the concentration of Cd2+ is 50 mg·L-1 and the initial pH value is 6.50,the Cd2+ removal rate reaches to 90.6% by putting 2 g of nano-cryptomelane into the sewage for 2 hours at 25℃.The adsorption isotherm is fitted by Langmuir model,and the theoretical maximum adsorption capacity is 120.5 mg·g-1 when the concentration of Cd2+ is less than 300 mg·L-1.The Cd2+ removal is realized by the co-work of the surface coordinate reactions,surface electrostatic adherences and ion exchanges of the synthetic nano-cryptomelane.