| 摘要 |
<p>1295658 Hydration of sodium tripolyphosphate UNILEVER Ltd 19 Dec 1969 [24 Dec 1968] 61954/69 Heading C1A [Also in Divisions B8 and C5] Sodium tripolyphosphate (STPP) is hydrated at least partially by contacting the STPP with superheated steam at at least one point during its conveyance through a pipe by means of a carrier gas (i.e. pneumatic conveyance) and removing the hydrated STPP from the pipe. The weight ratio of STPP to carrier gas is advantageously in the range 10 : 1 to 2 : 1 and the weight ratio of steam to carrier gas 1 : 25 to 3 : 10 producing STPP of up to 15% moisture content, corresponding to 65% hexahydrate content. The steam nozzles may supply steam at a rate such that the ratio steam: STPP at each contact point does not exceed 5 : 100 and the ratio steam : STPP along the line is 0À5 : 100 to 5 : 100. The steam may be superheated to 200‹C. for a saturation temperature of 105-150‹C. The flow rate of STPP at the steam contact points is advantageously in the range of 20 to 30 metres/sec. The process is suitable for STPP having a high or a low phase I content. An apparatus comprising a pipe 1 for conveying the STPP and having spaced at intervals inlets 10a, 10b, 10c, 10d, containing steam injection nozzles 12 is provided (see Division B8). The STPP may be used for detergent compositions (see Division C5).</p> |
