There are two by-products of domestic production of potassium hydroxide, one is membrane method (metal anode method) and the other is ion membrane method. The production process from the whole production of potassium hydroxide to the production of sodium hydroxide is basically the same (the process flow is the same). The difference only lies in the difference between raw and auxiliary materials and operation control.

　　(1)隔膜方法(陽極)金屬電解沉積氫氧化鉀流程簡報如下:將精制后遇到的需要金屬陽極電解槽中電解水注射氯化鉀與直流電電解,生成氫氧化鉀陰極室,通過蒸發(fā)器蒸發(fā)液體氫氧化鉀產(chǎn)品,如繼續(xù)濃縮、脫色、制作人,固體氫氧化鉀的產(chǎn)品。方程如下:

　　(1) Diaphragm method (anode) metal electrolytic deposition potassium hydroxide process is as follows: inject the electrolytic water in the metal anode electrolyzer after refining into potassium chloride and electrolyze with direct current to generate the potassium hydroxide cathode chamber, and evaporate the liquid potassium hydroxide products through the evaporator, such as continuous concentration, decolorization, producer and solid potassium hydroxide products. The equation is as follows:

　　(2)離子膜法電解氫氧化鉀的工藝流程。

　　(2) The technological process of potassium hydroxide electrolysis by ion-exchange membrane method.

　　使用氯化鉀為原料,淡鹽水流出離子膜電解槽后去除氯和脫氯塔在飽和鹽水罐是由飽和鹽水,然后添加氫氧化鉀,碳酸鉀和其他化學物質,鹽水進入沉降器澄清,但是定居者的精制鹽水和懸浮物,鹽水精制的螯合樹脂塔將產(chǎn)生不利影響,鹽水懸浮物一般要求小于1ppm，所以需要通過鹽水過濾器。然后經(jīng)過二次精制，即將鹽水放入螯合樹脂塔中除去鈣、鎂，可以加入到離子膜電解槽的陽極電池中;同時，純水和液態(tài)堿一起進入陰極腔。直流電進入陽極室后，產(chǎn)生氯氣，排出新鮮鹵水，鹵水被分離器分離，氯氣輸送到主氯管。鮮鹵水一般為kcl200-220g /l，槽內去氯、去飽和。電解槽的陰極室產(chǎn)生氫氣和30-32%的液基，液基也通過分離器，氫氣被輸送到氫氣和氧氣總管。30-32%的液基可以作為商品出售，也可以送到蒸發(fā)器將液基蒸48%作為商品出售，再濃縮成片劑和固體氫氧化鉀產(chǎn)品。

　　Using potassium chloride as raw material, the dilute brine flows out of the ion-exchange membrane electrolyzer to remove chlorine and dechlorination tower. In the saturated brine tank, the saturated brine is used, and then potassium hydroxide, potassium carbonate and other chemicals are added. The brine enters the settler for clarification, but the refined brine and suspended solids of the settler will have adverse effects on the refined chelating resin tower of the brine. Generally, the suspended solids of the brine are required to be less than 1ppm, so it is necessary to To pass through the brine filter. After secondary refining, the brine is put into the chelating resin tower to remove calcium and magnesium, which can be added to the anode battery of the ion-exchange membrane electrolyzer; meanwhile, pure water and liquid alkali enter the cathode cavity together. After the direct current enters into the anode chamber, chlorine gas is generated, and fresh brine is discharged. The brine is separated by the separator, and the chlorine gas is delivered to the main chlorine pipe. The fresh brine is generally KCl 200-220g / L, which is de chlorinated and desaturated in the tank. The cathode chamber of the electrolytic cell produces hydrogen and 30-32% liquid base. The liquid base also passes through the separator, and hydrogen is delivered to the hydrogen and oxygen header. 30-32% of the liquid base can be sold as a commodity, or sent to the evaporator to evaporate the liquid base to 48% as a commodity, and then concentrated into tablets and solid potassium hydroxide products.

　　(3)由于生產(chǎn)工藝的不同，產(chǎn)品質量也有一定的差異，離子膜法生產(chǎn)的產(chǎn)品雜質相對比膜法少，質量好，成本略高，略高。表2和表3分別為離子膜法和膜法的產(chǎn)品質量標準。

　　(3) Due to the different production process, the product quality also has certain differences. The product impurities produced by the ion-exchange membrane method are relatively less than that produced by the membrane method, with good quality, slightly higher cost and slightly higher price. Table 2 and table 3 are the product quality standards of ion-exchange membrane method and membrane method respectively.