Patents
The invention relates to a for recovery of nickel from spent nickel catalyst of an oil refinery plant. This invention particularly relates to a for of nickel from spent catalyst by direct leaching with sulphuric acid in presence of small amount of a small amount of promoter selected from chlorate, perchlorate, permanganate, iodate, periodate salts of Sodium, Potassium. The invention is useful for recovery of nickel from the waste material such as spent catalyst, which is one of the rich sources of nickel and therefore important from the view of environmental protection, resource recycling and conservation. Novelty of the invention is in the use of a promoter which has not been used earlier for direct leaching of nickel from nickel catalyst. Another feature of the invention is complete nickel dissolution (more than 99.5%) from the spent catalyst without any prior treatment such as reduction/alkali/chlorination roasting etc. which are necessary steps in earlier developments.