Abstract:
A process for the simultaneous replacement of a first catalyst by a second catalyst which first catalyst is circulating as a moving bed of solid particles in a hydrocarbon treating unit, which unit comprises at least one processing reactor. The first catalyst is withdrawn downstream of the reactor, or of each reactor, in the direction of catalyst circulation. The second catalyst is simultaneously injected upstream of the reactor or of each reactor. The bulk density of the material withdrawn downstream of the reactor, or of each reactor, is measured continuously. The withdrawal of the first catalyst and the injection of the second catalyst into the reactor concerned are interrupted when the bulk density so measured is equal to that of the second catalyst.
Abstract:
The invention concerns a jet engine fuel having the following characteristics:i) distilling range from 140 to 300.degree. C.;ii) cis-decalin/trans-decalin ratio greater than 0.2;iii) aromatics content less than 22% by volume;iv) sulfur content less than 100 ppm, andv) lower heating value per unit volume greater than 34.65 Mj/liter.Also process for making the same wherein for example a cut from catalytic cracking distilling between 140 and 300.degree.0 C. is subjected to a hydrotreatment step and then to a dearomatization step.