PROCESS FOR THE SELECTIVE RECOVERY OF TRANSITION METALS FROM ORGANIC RESIDUES

• Main Authors: Guidetti, Stefania, Angelis, Alberto Renato
• Format: Patent
• Language: English
• Published: 16.12.2021
• Subjects: CHEMISTRY; CRACKING HYDROCARBON OILS; FERROUS OR NON-FERROUS ALLOYS; FUELS; LUBRICANTS; METALLURGY; MINERAL WAXES; PEAT; PERFORMING OPERATIONS; PETROLEUM, GAS OR COKE INDUSTRIES; PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL; PRETREATMENT OF RAW MATERIALS; PRODUCTION AND REFINING OF METALS; PRODUCTION OF LIQUID HYDROCARBON MIXTURES, e.g. BY DESTRUCTIVEHYDROGENATION, OLIGOMERISATION, POLYMERISATION; RECOVERY OF HYDROCARBON OILS FROM OIL-SHALE, OIL-SAND, ORGASES; REFINING MIXTURES MAINLY CONSISTING OF HYDROCARBONS; REFORMING OF NAPHTHA; SEPARATION; TECHNICAL GASES CONTAINING CARBON MONOXIDE; TRANSPORTING; TREATMENT OF ALLOYS OR NON-FERROUS METALS

There is a process for the selective recovery of transition metals from an organic stream containing transition metals. The organic stream and possibly a first extractor if solid, are melted up to the liquid state. The extractor consists of an ionic liquid or a mixture of two or more ionic liquids and the ionic liquid contains an ammonium salt as cation and as anion an anion with chelating properties. A melted organic stream and a first extractor, optionally melted, are fed to a first liquid-liquid extraction unit working at a temperature of at least 150° C. where the liquid-liquid extraction is carried out obtaining a liquid mixture containing an ionic liquid, or a mixture of two or more ionic liquids, and metals. After extraction, the liquid mixture is cooled at a temperature between 0° C. and 70° C. and becomes biphasic; then the cooled mixture is sent to a first separation unit, to separate a liquid phase that contains ionic liquids and metals, and a metal-depleted solid phase. After the first separation, the separated metal-depleted solid phase is optionally sent to a washing unit to which a solvent is fed, so as to eliminate the residual ionic liquid by transferring it into the solvent and obtaining a metal-depleted solid phase. Then the separate liquid phase containing ionic liquids and metals is sent into a liquid-liquid precipitation and separation unit, adding a counter-solvent, thereby obtaining a solid phase containing the metals and a liquid stream containing counter-solvent and ionic liquids.