摘要 |
FIELD: chemical engineering. SUBSTANCE: invention relates to preparation of granulated materials having low melting and destruction temperatures such as dimethylaminoborane used as reducing agent in organic synthesis and in non-electric metallization process. Method of invention includes melting of substance, dispersing of melt into drops, and crystallization of drops upon cooling below solidification temperature of drops. Novelty consists in that dispersing of melt into drops is effected under constant pressure of melt and pressure of inert gas 0.02-0.05 MPa and crystallization is performed in two steps: drops are preliminarily cooled to temperature from -5 to -20 C for 5- 10 s and then to temperature from -25 to -35 C for 30-50 s, after which solidified granules are dropped into container for collection of final product. In the proposed method, melting should be advantageously performed at 38-42 C and pressure of inert gas 0.02- 0.03 MPa, feeding drops into crystallization should be performed by way of their free fall in inert gas atmosphere with feeding rate 2 to 20 kg/h, and cooling should be performed on cooled tape continuously moving with constant velocity, e.g. 0.10 m/s, whereas wetting angle of dimethylaminoborane to tape is <EMI ID=0.137 HE=3 WI=3 TI=CHI> 63.5 deg. EFFECT: enhanced process efficiency. 4 cln
|