A hydrometallurgical process for recovery of metals and/or semimetals from waste materials, such as high-tech or green-tech wastes, and/or electrical and electronic waste containing compound semiconductor materials and/or back contact materials and/or transparent electrically conducting oxides (TCOs), wherein the waste materials according to the invention are mixed thoroughly with a reaction solution of water, 1 to 5% by mass sodium bisulphate and 1-5% by mass sodium chlorite or with a reaction solution of water, 1 to 50% by mass organosulphonic acid and in the stoichiometric ratio to the organosulphonic acid 1-5% by mass of an oxidizing agent, and the metals and/or semimetals that are to be recovered are dissolved.