A Zero-Waste Process for the Treatment of Spent Potliner (SPL) Waste

This work presents a deep analyses of an environmentally friendly process to recover all valuable minerals contained in the spent potliner (SPL) such as graphite carbon and aluminum fluoride (AlF3) and production of sodium sulfate (Na2SO4) and gypsum (CaSO4) when H2SO4 is used as the leaching agent. The level of emission of hazardous gases such as HCN (weak acid) and HF are minimized by direct scrubbing of the HCN in aqueous AgNO3 solution to produce a stable silver cyanide (AgCN) product. The HF can be recovered as a liquid by condensation and used within the process and/or in production of metal fluorides such as the highly-soluble potassium fluoride (KF); a main source of fluoride in industry. Almost pure CO2 gas is also recovered from the process gas streams.

A new chromogenic and fluorescent chemosensor based on a naphthol–bisthiazolopyridine hybrid: a fast response and selective detection of multiple targets, silver, cyanide, sulfide, and hydrogen sulfide ions and gaseous H2S

This optical probe selectively recognized the titled analytes by the color changes, which are applicable by solution or solid kits.

A closed-loop electrogenerative recycling process for recovery of silver from a diluted cyanide solution

A closed-loop process for the complete recovery of silver from a diluted silver cyanide solution has been constructed based on an electrogenerative process.

Silber(I)-cyanid-Komplexe mit Aminen und Azaaromaten

Silver cyanide can be treated with liquid amines or azaaromaticsLto give crystalline complexes of various compositions, among them complexes of the simple type cyanido(amine)silver(I):L=isobutylamine and 4-picoline. Other AgCN:Lratios obtained were: 1:2 (benzylamine and 4-benzylpiperidine), 2:1 (2,4-lutidine), 2:3 (morpholine and 3,4-lutidine) and 3:4 (3,5-lutidine). The packing diagrams were analyzed in terms of Ag–Ag and Ag–CN contacts and N–H···N hydrogen bonds. The contacts often give rise to chains, which are sometimes linked to layers by hydrogen bonds.

An Innovative Model of Managing Silver Metal from Electronic Scrap Using a Combination of Chemical Leaching Followed by Biosorption and Biodegradation

This paper attempts to propose an innovative strategy/model for the recovery of precious metal like silver from e-waste by employing combined technologies. Firstly, silver is leached using free cyanide from electronic scrap thereby forming silver-cyanide complex. In the second step, silver-cyanide is removed using biosorption using passiveEicchorniaroots powder biomass. Lastly, the residual silver-cyanide remaining after biosorption is biodegraded using live heterotrophic bacterial consortium. Feasibility study showed that the overall system strategy worked efficiently for the management of e-waste.