KOH活化石墨毡阳极用于印刷电路板蚀刻液的电解再生

Preparation and Performance of KOH Activated Graphite Felt Anode for Electrolytic Regeneration of PCB Etchant

石墨毡电极的润湿性和电化学活性对印刷电路板蚀刻液电解再生装置的性能有重要影响。在900℃下,用KOH对石墨毡进行活化处理,并将KOH活化石墨毡作为电解池阳极对酸性蚀刻废液进行电解再生。用SEM、XPS表征和分析了活化前后石墨毡炭纤维的表面形貌和元素组成。通过循环伏安(CV)和电化学阻抗谱(EIS)分析了石墨毡电极的电化学性能。结果表明,KOH活化石墨毡炭纤维表面含氧量由原始石墨毡的2.60%(原子百分数,下同)增加到6.27%,润湿性得到改善。缺陷C数量增多,对Cu(I)电化学氧化活性提高。KOH活化石墨毡比表面积较原始石墨毡增加了约42倍。KOH活化石墨毡用于电解实验,阳极电势和槽电压较原始石墨毡分别降低0.10和0.05~0.06 V。

The wettability and electrochemical activity of the graphite felt（ GF） have a significant impact on the performance of the apparatus for electrolytic regeneration of PCB etchant. GF activated with KOH at 900 ℃ is employed as the anode of the cell for electrolytic regeneration of acidic CuCl_2 etchant. The morphology and the element composition of activated GF and untreated GF are characterized by SEM and XPS,respectively. The electrochemical performance of the two GF electrodes is evaluated through cyclic voltammetry（ CV） and electrochemical impedance spectroscopy（ EIS）. The results show that the oxygen content of the activated GF increases to 6. 27 at% from 2. 60 at% of the untreated GF,and the wettability is improved. The electrochemical activity towards oxidation of Cu（ I） is improved,which can be ascribed to the increase of the number of the defective carbon. The BET specific surface of the GF increases by - 42 times after KOH activation. The anode potential and the cell voltage of the activated GF decreasesby 0. 10 V and 0. 05 - 0. 06 V,respectively,compared with the untreated GF in the etchant electrolytic regeneration experiment.