| 摘要 |
<p>1388160 Zinc sulphate purification SOC de PRAYON 15 June 1972 [23 June 1971] 27997/72 Heading ClA In a process for purifying an iron-containing zinc sulphate solution comprising precipitating the iron at a pH <4 as the basic sulphate, jarosite or goethite, decanting the slurry obtained and filtering the underflow from the decanter, the underflow is filtered on a continuous, plane, horizontal, filtration surface and the residue is washed on the filter surface thus freeing the cake from water-soluble zinc and copper compounds before a significant amount of hydrolysis to water-insoluble basic sulphates can take place. Several countercurrent washings may be provided by recycling the wash liquid on to the cake.</p> |
