电渗析器免拆清洗实例

用静态溶垢试验和静态模拟试验选出的清洗剂清洗电渗析器，结果表明：用质量分数为2％ HCl，5％多聚磷酸盐，2％HCl 2％CaCO3，0.1mol／L NaOH依次循环清洗电渗析器可清洗掉常见电渗析器垢物和污染物．     

A study on the removal of urea from aqueous solution with immobilized urease and electrodialysis

A five-compartment electrodialyzer with immobilized urease was developed for the removal of urea from aqueous solution. The immobilized urease, supported on polyurethane foam, was placed in the central (dilute) compartment, where urea was hydrolyzed and the products NH₄⁺ and CO₃^2-/HCO₃^? were removed simultaneously by electrodialysis. The system was studied both under constant current and under constant voltage. The effects of urea concentration and applied current or voltage on the removal of urea and ammonium ions from the dilute solution were investigated. The variations of the pH of dilute solution, the current or voltage of system, and current efficiency were also examined during reaction-electrodialysis. The removal of urea by enzymic reaction was not affected significantly by the applied electric field. The current effieiencies for removing ammonium ions from dilute solution were mostly within 40-80%, and the removal percentage of ammonium ions was dependent on current density and current efficiency.     

一种低温煤焦油混合酚钠盐的分解新方法

低温煤焦油含有苯酚、甲酚、二甲酚等几十种多取代苯酚类化合物,提取苯酚类化合物现有两种方法,最常用的酸碱法虽简便,但产生大量废酸、废碱,会污染环境、腐蚀设备等;溶剂萃取法污染较少,但操作复杂,成本增加,并降低剩余煤焦油加氢制燃料的收率。本文介绍了一种低温煤焦油混合酚钠盐的分解新方法,采用由两个双极性膜和一个阳膜为基本单元构成的双极膜电渗析装置,分解混合酚钠盐,生成混合苯酚化合物。可以有效解决传统煤焦油加工技术中大量酸、碱废水的排放,是一项绿色化学工艺技术。