A process for the manufacture of crude dipentene from crude rubber and for the recovery of liquid rubber
Реферат: 235,380. Bamber, M. K. June 5, 1924. Distilling plant. -Waste crude scrap or vulcanized rubber is heated in a still to a temperature not exceeding 350‹ C. at a pressure not exceeding two atmospheres until about half to three-quarters of the charge is vaporized, the distillate is condensed at about atmospheric pressure yielding a liquid consisting mainly of crude dipentene, and a gas which is led to the furnace for heating the still, and the liquid residue, called " liquid rubber," is collected and used as a substitute for drying oils. By varying the pressure in the still, the ratio of condensable to uncondensable vapours may be varied, a high pressure producing less dipentene. The viscosity of the liquid residue is low when half the charge is volatilized, and increases as the distillation proceeds. A suitable still consists of an inclined cylinder 30 with an outlet 31 for the liquid rubber and outlet 32 for the vapours. The charge is admitted .through an opening 33, a sliding door 35 preventing the escape of vapour. A grid 38 separates the melted from the unmelted rubber.
Process for the selective hydrogenation of the keto group in nonconjugated olefinic ketones
Номер патента: CA1086332A. Автор: Peter S. Gradeff,Giuseppe Formica. Владелец: Rhodia Inc. Дата публикации: 1980-09-23.