| 摘要 |
<p>Prodn. of phthalic anhydride by passing a naphthalene, air mixt. through a fluidised bed contg. a K2O:V2O5 molar ratio 1-6 and a softening temp. 320 deg.C catalyst deposited, at 1-35%, by wt. total mass, as a glass on silica gel of pore size 40-60A and max. sieve size 50 B.S. V2O5 and K2O mixt. is melted, cast, ground to 100 BS sieve size and mixed in a tumbling mill with silica gel of pre size 40-60 angstrom and particle size 50-200 B.S. The mixt. is placed in a hopper and passed through a control valve to a fluidising column. Preheated compressed air is introduced through a distributing ring at the base and flows through the particles to maintain them in a fluidised state. Column temp. is 350-400 deg.C.</p> |
