Abstract: A process for processing a leach solution of black mass of spent alkaline batteries which leach solution comprises metals dissolved to an acidic solution. The process comprises removing of one or more elements from the leach solution by a cementation operation by applying at least one non-noble metal in a metal form as a cementation agent and one or more additional cementation agents from both sulphate and nitrate groups to process the leach solution into a product of at least manganese- and zinc-containing sulphate solution which is suitable for use as micronutrients alone, in fertilizers and/or together with a plant protective agent to aid growth and health of plants. In addition, the invention also relates to a process for processing a black mass of spent alkaline batteries.