| 摘要 |
<p>Diphenylamine is manufactured by a continuous vapour phase process which comprises passing undiluted aniline vapour at superatmospheric pressure into a reaction chamber maintained at 400-550 DEG C. and containing a non-base-exchanging catalyst such as alumina, titania, or bauxite; condensing the effluent from the reaction chamber, and separating the diphenylamine formed from excess aniline and ammonia. Specified pressures are 15-100 p.s.i.g. The aniline vapour is passed at a rate of between 15 and 2000 parts by weight of liquid aniline per hour per 100 parts by weight of catalyst. The aniline feed is stopped after a suitable period and air or other oxygen-containing gas is passed through the catalyst bed to burn off accumulated tar and carbonaceous matter, and regenerate the catalyst. In examples the process is described using various pressures, temperatures, feed rates and catalysts. Specification 473,739 is referred to.</p> |
