A process for the enhancement of the iron arrears to extend from the hydrometallurgical recovery of zinc

摘要

Jarosite-type residues obtd. in the hydrometallurgical prodn. of Zn are calcined until more or less all of the Fe salts have transformed into oxides. Volatile products given off during calcination are recovered and treated to give a cpd. contg. sulphate anions. The solids are washed to give a red pigment of Fe. The red pigment is used in anticorrosive paints and for colouring bitamens, bricks and tiles. The volatile prodts. can be used to produce H2SO4 or dihydrating CaSO4, waste, normally stored and often leading to pollution of the environment, is effectively utilised.