PRODUCTION OF NON-CAKING BLENDS OF SODIUM TRIPOLYPHOSPHATE HEXAHYDRATE AND SODIUM NITRILOTRIACETATE MONOHYDRATE OR DIHYDRATE

摘要

1300507 Blend of sodium tripolyphosphate and sodium nitrilotriacetate KNAPSACK AG 19 April 1971 [20 Feb 1970(2)] 22123/71 Addition to 1219749 Heading C5D A non-caking blend of sodium tripolyphosphate hexahydrate and sodium nitrilotriacetate monohydrate or dihydrate is prepared by spraying water or an aqueous solution as hereinafter defined having a temperature of between 0 and 80‹ C., on to anhydrous sodium tripolyphosphate or a blend of anhydrous sodium tripolyphosphate and sodium nitrilotriacetate, which is constantly agitated, the aqueous solution being used in quantities sufficient to provide all the water needed for the formation of the hexahydrate and when an excess proportion of water is used simultaneously flowing a gas and/or air stream over the sprayed material to evaporate the water in excess. The aqueous solution contains (a) a portion of the anhydrous sodium tripolyphosphate, (b) a portion of the anhydrous sodium tripolyphosphate or (c) a portion or the whole of the sodium nitrilotriacetate together with a portion of the anhydrous sodium tripolyphosphate. When water alone is the spray, the blend to be sprayed contains the overall quantity of the anhydrous sodium tripolyphosphate and sodium nitrilotriacetate. Carboxymethyl cellulose may be incorporated as a binder. The blends may contain 20-70% by wt. of sodium nitrilotriacetate.