Abstract
The lack of developed method for the treatment of acidic copper etching wastewater has always been a tricky problem in the printed circuit board (PCB) industries. In this study, an improved approach of decomplexation & neutralization & precipitation by NH3·H2O coupling with oxidation by O2 for the removal of Cu(II) and Cu(I) from acidic copper etching wastewater was explored. After the wastewater being treated using NH3·H2O with the constant addition of O2 at 30 °C under the v(NH3·H2O):v(waste) of 0.35, 96.9% of Cut was effectively removed in the form of Cu2(OH)3Cl precipitates. The removal mechanisms for Cu(II) are as follows. (1) NH3·H2O reacts with H+, leading to the enhancement in the pH value. (2) Cu(II)-Cl(-I) complex reacts with NH3·H2O to produce Cu2(OH)3Cl. For Cu(I), the removal mechanisms were proposed as follows. (1) The stable CuCl43− is de-complexed by NH3·H2O to produce Cu(NH3)4+. (2) Then, Cu(NH3)4+ is oxidized by O2 to produce Cu(NH3)42+. (3) Cu(NH3)42+ reacts with Cl(-I) and H2O to produce Cu2(OH)3Cl.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
