申请人:Sachem, Inc.
公开号:EP0834346A2
公开(公告)日:1998-04-08
In one embodiment, the invention relates to a process for purifying solutions containing a hydroxide compound, including the steps of: (A) providing an electrochemical cell containing an anode, a cathode, a cation selective membrane and a bipolar membrane, the bipolar membrane having an anion selective side facing the anode and a cation selective side facing the cathode, wherein the cation selective membrane is positioned between the anode and the bipolar membrane, and the bipolar membrane is positioned between the cation selective membrane and the cathode, thereby defining a feed compartment between the cation selective membrane and the anode, a recovery compartment between the bipolar membrane and the cation selective membrane, and a water compartment between the bipolar membrane and the cathode; (B) charging a solution of an ionic compound at a first concentration to the water compartment, and water to the recovery compartment; (C) charging a solution containing the hydroxide compound at a second concentration to the feed compartment; (D) passing a current through the electrochemical cell to produce the hydroxide compound at a third concentration in the recovery compartment; and (E) recovering the hydroxide compound from the recovery compartment.
在一个实施方案中,本发明涉及一种用于纯化含有氢氧化化合物溶液的工艺,包括以下步骤:(A) 提供包含阳极、阴极、阳离子选择性膜和双极性膜的电化学电池,双极性膜具有朝向阳极的阴离子选择性侧和朝向阴极的阳离子选择性侧,其中阳离子选择性膜位于阳极和双极性膜之间,双极性膜位于阳离子选择性膜和阴极之间、双极性膜位于阳离子选择性膜和阴极之间,从而在阳离子选择性膜和阳极之间形成进料室,在双极性膜和阳离子选择性膜之间形成回收室,在双极性膜和阴极之间形成水室;(B) 将第一浓度的离子化合物溶液注入水室,并将水注入回收室; (C) 将含有第二浓度氢氧化化合物的溶液注入进料室; (D) 将电流通过电化学电池,以便在回收室中产生第三浓度的氢氧化化合物;以及 (E) 从回收室中回收氢氧化化合物。