含镍三氯化铁蚀刻废液再生研究

Study of the Regeneration of FeCl_3 Waste Etching Solution Containing Ni

以铁粉为还原剂,再生含镍三氯化铁蚀刻废液.一阶段将蚀刻废液中的Fe3+还原成Fe2+;二阶段置换去除其中的Ni 2+;将除镍废液经H2O2氧化后转化成FeCl3溶液.实验过程中系统考察了废液稀释比、反应时间、铁粉加入量、反应温度、H2O2和HCl混合液加入量对蚀刻废液再生效果的影响.结果表明,在Fe3+还原Fe2+的优化反应条件下(稀释比为1∶1,反应时间为1h,铁粉加入量为理论量1.2倍,反应温度为60℃),Fe3+的最佳还原率达95.7%;在Fe粉置换Ni 2+的优化反应条件下(铁粉加入量为理论量3倍,反应温度为85℃,反应时间为3h),Ni 2+的最佳置换率达86.6%;在利用H2O2氧化Fe2+的优化反应条件下(H2O2和HCl混合液加入量与废液体积比为1∶1),Fe2+的最佳氧化率达94.4%.处理后的废液建议经浓缩、组分调整处理后循环使用.

At the first stage,iron powder was added to the waste etching solution and Fe^3＋ was reduced to Fe^2＋ ; at the second stage, Ni^2＋ in the waste solution was replaced by iron powder; at the final stage, FeCl2 was oxidized into FeCl3 by adding H2O2. The effects of dilution ratio, reaction time, the amount of iron powder added, reaction temperature, the added amount of the mixture of H2 O2 and HCl on the waste etching solution regeneration were systematically investigated. The results showed that under the optimum conditions of reducing Fe^3＋ to Fe^2＋ （ dilution ratio 1： 1, reaction time 1 h, the amount of iron powder added 1.2 times, reaction temperature 60℃）, the reduction rate of Fe^3＋ reached 95.7%. Under the optimum conditions of replacement Ni^2＋ （ the amount of iron powder added 3 times, reaction temperature 85℃, reaction time 3 h）, the replacement rate of Ni^2＋ reached 86.6 %. Under the optimum conditions of oxidation of Fe^2＋ by using H2O2, the oxidation rate of Fe^2＋ reached 94.4%. After the enrichment process and solution component adjusted, the treated waste etching solution can be recycled in etching process.