Recovery of copper from printed circuit board (PCB) acidic etching wastewater: Ammonia regulates the crystallization of high valued copper salt was written by Guo, Yi;Zheng, Jiayi;Yan, Xu;Liu, Xueming;Xu, Wenbin;Liu, Weizhen;Li, Xiaoqin;Lin, Zhang. And the article was included in Surfaces and Interfaces in 2022.Electric Literature of CuH2O2 This article mentions the following:
In electronic and elec. industries, a huge amount of acidic cupric etching wastewater was produced during the manufacture of printed circuit board (PCB). Reclamation of copper is necessary for resource recovery and environmental protection. Herein, ammonia (NH3·H2O) and sodium hydroxide (NaOH) were investigated and compared as neutralizers to regulate the sequential crystallization of basic copper chloride (Cu2(OH)3Cl), copper hydroxide (Cu(OH)2), and copper sulfate (CuSO4·5H2O). Crystal phase and micro-morphol. were analyzed by X-ray diffraction and scanning electron microscope; product quality was evaluated by laser particle size analyzer, thermogravimetry, and inductively coupled plasma. The results showed that ammonia as the neutralizer can regulate the formation of spherical Cu2Cl(OH)3 particles with compact surface, good fluidity, and low moisture-absorption-ability, which can be used as a precursor to producing Cu(OH)2 and CuSO4·5H2O with higher purity. Mechanism anal. revealed that ammonia acts as ‘a storage of OH– and Cu2+‘ in the aqueous phase due to its weak alkalinity and the ability to complex with Cu2+ to form stable Cu(NH3)2+n. As a result, OH- and Cu2+ were slowly released to the solution and slowed down the crystallization kinetics of copper-containing precipitates This work proposed a promising and harmless resource recycling method, and also inspired the understanding and utilization of metal crystallization law in the ammonia buffer system. In the experiment, the researchers used many compounds, for example, Cuprichydroxide (cas: 20427-59-2Electric Literature of CuH2O2).
Cuprichydroxide (cas: 20427-59-2) belongs to copper catalysts. Transition metal-catalyzed chemical transformation of organic electrophiles and organometallic reagents belong to the most important cross-coupling reaction in organic synthesis. Copper nanoparticles can also catalyze the coupling reaction of phenols, thiols, xanthogenates, nitrogen-containing nucleophiles, selenium ruthenium nucleophiles and the like.Electric Literature of CuH2O2
Referemce:
Copper catalysis in organic synthesis – NCBI,
Special Issue “Fundamentals and Applications of Copper-Based Catalysts”