Described is a method of recycling the sludge which arises during the zinc-phosphating of steel surfaces. The sludge is preferably digested with nitric acid, the iron selectively extracted from the digested solution by liquid/liquid extraction and the extract thus obtained re-used in the preparation of zinc-phosphating solution. The preferred extraction solvent is a solution of phosphoric acid mono-2-ethylhexyl ester in kerosine.
申请公布号
DE4032956(A1)
申请公布日期
1992.04.23
申请号
DE19904032956
申请日期
1990.10.18
申请人
HENKEL KGAA, 4000 DUESSELDORF, DE
发明人
BUCHMEIER, WILLI, DR., 4000 DUESSELDORF, DE;ROLAND, WOLF ACHIM, DR., 5650 SOLINGEN, DE
