MUMBAI, India, Aug. 31 -- Intellectual Property India has published a patent application (202641100672 A) filed by Minimines Cleantech Solutions Private Limited on August 20, 2026, for A Process For Selective Nickel Recovery From Spent Catalysts Using Recyclable Choline Chloride-Sulfonic Acid Des.
Inventors include Anupam Kumar; and Arvind Bhardwaj.
The application for the patent was published on August 28, 2026, under issue no. 35/2026.
Abstract: A PROCESS FOR SELECTIVE NICKEL RECOVERY FROM SPENT CATALYSTS USING RECYCLABLE CHOLINE CHLORIDE-SULFONIC ACID DES The invention relates to hydrometallurgical recovery of nickel from spent nickel catalysts. A spent catalyst containing nickel sulphide, nickel oxide, alumina, sulphur-bearing species, iron, and carbonaceous deposits is first calcined in an oxidizing atmosphere to convert sulphides to nickel oxide, remove carbon, and evolve sulphur oxides, followed by off- gas scrubbing, cooling, and size reduction. Nickel is then selectively dissolved using a deep eutectic solvent formed from choline chloride and an organic sulfonic acid at about 1:2 molar ratio, the solvent exhibiting proton activity and chloride-based stabilization of soluble nickel-chloro complexes [NiCl3]- and [NiCl4]2-. After solid-liquid separation, dissolved iron is removed by controlled pH adjustment, and metallic nickel is recovered by electrowinning or electrodeposition. The depleted solvent is dehydrated and replenished with fresh sulfonic acid for reuse. The process improves selectivity, solvent recyclability, and alumina residue valorization in nickel recovery.
Disclaimer: Curated by HT Syndication.
