Recovery of metallic copper from waste printed circuit boards via H3NO3S-NaCl-H2O2 leaching system

Chemically Benign Electrometallurgical Treatment of Waste-Printed Circuit Board in Polyethylene Glycol for Metal Recovery

“…Still, the upkeep of cost and energy consumption effectiveness remains challenging. For HM, corrosive chemicals are required to induce metal leaching. , Highly toxic acidic and alkali leaching reagents, such as H 3 NO 3 S-NaCl-H 2 O 2 , NH 3 -(NH 4 ) 2 SO 4 , cyanide, halide, thiourea, and thiosulfate, are most frequently utilized for common metal extractions or precipitation, such as Sn, Pb, Fe, Cu, and Zn. , HM’s metal leaching selectivity and efficiency could be controlled and tailored with solvent selection, making it generally more suitable to handle more valuable metals than PM. However, the non-pH-neutral solvent and the generation of toxic fume release from metal dissolution are the common criticisms for employing HM as a metal leaching strategy, and it requires a stoichiometric amount of acid or alkaline reagents that induces substantial chemical and post-treatment processing cost.…”

Environment-friendly acids for leaching transition metals from spent-NMC532 cathode and sustainable conversion to potential anodes

“…In the case of p-toluenesulfonic acid (p-TSA) and sulfamic acid (SA) very much less research has been done in the recycling eld, especially for the leaching of transition metals. 43,44 p-TSA is a strong organic acid and it is used as a hydrogen bond donor of deep eutectic solvents, which are reported to be economically and environmentally sustainable agents. It has a higher degree of selective recovery of metals, its water solubility limit is good and it is cost effective.…”

“…This acid is not harmful either to living systems or to non-living systems and the production of harmful gases is relatively minimal. [43][44][45][46] Mostly in the case of organic acids, the functional groups play a major role. Since p-TSA has sulfonyl groups, it ionizes completely in an aqueous medium and produces H + ions faster than other acids.…”

“…So, comparing these two acids with HCl and H 2 SO 4 environmentally, economically and experimentally, these acids are feasible, non-toxic, show low corrosiveness and are efficient at leaching metals. [43][44][45][46][47][48] Herein, we have demonstrated a simple, facile approach for recycling an NMC532 cathode with the aid of two different acids, namely p-TSA and SA, respectively. These acids can be used for leaching transition metals from an NMC532 cathode and subsequently form mixed metal oxalates.…”