Selective removal of nickel from iron substrate by non-cyanide strippers①
(1. School of Resource and Environment, Central South Forest University, Changsha 410004, China;2. School of Resources Processing and Bioengineering, Central South University,
Changsha 410083, China;3. Department of Mining and Metallurgical Engineering, McGill University,Montreal, QC, H3A 2B2, Canada)
Changsha 410083, China;3. Department of Mining and Metallurgical Engineering, McGill University,Montreal, QC, H3A 2B2, Canada)
Abstract: A novel nickel stripper using ammonia as the key component was developed to substitute cyanide for removing nickel film from iron substrates. Its compositions are: ammonia 150 g/L, hydrogen peroxide 50 g/L, ammonium chloride 100 g/L, EDTA 7.5 g/L, copper chloride 15 g/L and glucopyrone 1.2 g/L. The optimum operating conditions are: pH 9.5 11, temperature 40 50℃and stripping time 1 h. It shows many advantages over the traditional cyanide stripper including no toxicity, mild operation, lower cost, larger holding capacity, faster stripping rate and good protection for the base metal, and can meet the technical requirements in industry.
Key words: nickel stripping; non-cyanide composition; environment-friendly technology