US2322794A - Hydrocarbon conversion - Google Patents

Description

y z u U G. EGLOFF NM. QM. NJN NN HYDROCARBON CONVERSION Filed May 5l, 1940 June 29, 1943.

Patented June 29, -1943 HYDROCARBON' CoNvERsIoN Gustav Egloi, Chicago, Ill., assignor to Universal Oil Products Company, Chicago, Ill., a corporation of Delaware Application May 31, 1940, Serial No. 338,167

4 Claims.

This invention relates to a process for convert- Ing hydrocarbon oil into substantial yields of high antiknock gasoline and further improving the antiknock value o! hydrocarbon fractions boiling substantially within the gasoline range.

More specically it relates to a process for producing high antiknock gasoline by contacting hydrocarbon distillates with powdered cracking catalysts under conditions adequate to produce high yields of desirable motor fuel.l The fractions contemplated for conversion include naphtha, kerosene, gas oil, wax distillate and the like, preferably `of petroleum origin, although similar suitable stocks from other hydrocarbon sources may likewise be employed.

In one specic embodiment the present invention comprises contacting naphtha with a powdered catalytic agent under cracking conditions oi temperature and pressure, separately contacting a higher boiling hydrocarbon fraction containing substantially no gasoline with a powdered catalytic agent in a second step, combining the reaction products under conversion conditions of temperature and pressure, i'ractionating the reaction products, recovering gas and gasoline and recycling a portion of the insuillciently converted oil boiling above the gasoline range. A part ot the process gases may also be recycled.

'I'he invention is further understood by reference to the accompanying drawing which is diagrammatic and should not' be construed as limiting it to the exact conditions of apparatus shown therein.

Naphtha charging stock which may be cracked or straight' run is introduced through line I,

of approximatny coo-1200 F. The reaction A products pass through line 33 containing valve I4 to fractionator 35. Gasoline and gas are recovered through line 36 containing valve 31, condenser and valve 39 entering receiver 40. The

gasoline is removed through suitable stabilizers,

not shown, through line 4I and valve 42. AA portion of the process gases may be removed through line 43 and valve 44. Another portion of the process gases may be recycled through 1ine V45 containing valve 46, pump 41 and valve 48, joining with line I and thus being passed lthrough coil 5 for further conversion.v Alternatively the recycled process gases may bypass heaters 5 and 24 and pass directly to'heater I5. Higher boiling Iractionator bottoms may be removed fromfrac- Vtionator 35 through line 49 and valve 50. A part through line 49 and may be recovered therefrom` by suitable means and maybe regenerated for l further use. or in certain instances may' be d iscarded. The catalytic agents employed in the present process may vary considerably 'and it is not es'- sential that the same catalyst be used in the various steps. The amount of catalyst used is apand valve I3 to line I4 and valve I5 and thence to coil I6 which is disposed in heater I1. In place ot coil II, a heated or unheated reaction chamber.

may be used. Although shown Aas a coil, this-may comprise any type of reaction zone, such as a reactionv chamber. A gas oil charging stock is in` troduced through line I8, valve I9, pump 2li, valve 2|, line 22 and -valve'23 to coil 24 which is disposed in heater 25. A powdered cracking catarst step for reforming the naphtha may comproximately 0.1-l0% and preferably 0.5-5% by weight of oil. The catalytic agent used in the prise alumina, bauxite, magnesite, etc., or may comprise one or more of these materials, having deposited thereon promoting oxides of chro! mium, molybdenum, tungsten, vanadium, titanium, zinc oxide and the like. These agents are used as a ne powder, preferably of particle size approaching colloidal dimensions. I

lyst is introduced from catalyst, charger 23 55 The catalytic agent employed 11n the second step for cracking the higher boiling oil may co prise the so-called silica-alumina, silica-zirconia and silica-alumina-zirconia catalysts which may. have added thereto minor portions of promoting compounds and particularly the oxides of elements such as chromium, molybdenum, vanadium, thorium, titanium andthe like, and which are preferably prepared by the separate or simultaneous precipitation of the components under conditions such that nely divided powder l esults. This may then be followed by suit le washing and drying steps so that alkalil metal ions aresubstantially eliminated. It is within the scope of the invention to use naturally-occurring earths or clays which may or may not have been further activated by chemical treatment, for example, with strong mineral acids.

As an alternative, a suitable catalyst for the primary reforming step comprises a mixture vof the catalysts just mentioned with those described vabove in connection with the primary reforming step. Thus, for example, when bauxite or alumina is used in the primary step and silica-alumina is used in the secondary step, the two catavlysts are mixed and recovered as a mixture. 'This mixed catalyst maybe reactivated by treatment with an oxygen-containing gas whereby the carbonaceous and hydrocarbonaceous deposits are removed, and a portion of the regenerated material may be returned to the primary reforming step, being mixed with the fresh reforming catalyst.

Since comparatively small quantities of catalytic agents are employed vand since these catalysts may be relatively inexpensive, it is not necessary to completely recover them and in some instances they may be discarded without further use. f

It should be borne in mind that vthe various catalytic materials described are not necessarily exactly equivalent in their action.

The following example is givengto illustrate the practicability and utility of.. the process, but should not be construed as ,limiting it to the exact conditions or catalytic materials used therein. Y Y

A Pennsylvania naphtha having an octane number of approximately 30 may be mixed with a powdered catalyst consisting essentially of a major portion of alumina having deposited thereon a relatively minor portion of chromia and reformed at a temperature of approximately 1075 F. A gas oil charging stock may be mixed with a silica-alumina composite and converted at a temperature of'approximately 1000 F. The reaction products are mixed and maybe treated at a temperature of approximately 1050 F. and finally fractionated to recover gasoline and gas. portion of ,the insuiilciently converted oil boiling above the gasoline range may be returned to the gas oil cracking step. A portion of the' process gases may be returned to the naphtha reforming step. A yield of approximately 80% of 79 octane number gasoline, together with small quantities of gas and higher boiling oil suitable for use as a fuel oil, may be recovered in this manner. I claim as my invention:

l. A process for the productionA of high antijknock gasoline, which comprises catalytically reforming a relatively light oil in the presence of a powdered dehydrogenating catalyst, simultaneously therewith catalytically cracking a heavier hydrocarbon oil in the presence of a powdered cracking catalyst which is diierent from the dehydrogenating catalyst, combining products of reaction from both conversion steps, subjecting the mixture to continued conversion in the presence of the mixed dehydrogenating and cracking catalysts, and thereafter separating gasoline from lower and higher boiling conversion products.

2. A process for the production of high antlknock gasoline, which comprises catalytically reforming a relatively light oil in the presence of a powdered dehydrogenating catalyst, simultaneously therewith catalytically cracking a heavier hydrocarbon oil in the presence of a powdered cracking catalyst comprising a siliceous material which is different from the dehydrogenating catalyst, combining products of reaction from both conversion steps, subjecting the mixture to continued conversion in the presence of the mixed dehydrogenating and cracking catalysts, fractionating resultant conversion products to separate fractionated vapors in the gasoline boiling range from higher boiling conversion products and returning at least a portion of said higher boiling conversion products to the second mentioned conversion step.

3. A process for the production of high anti; knock gasoline, which comprises catalytically reforming a relatively light oil in the presence of a 'powdered dehydrogenating catalyst, simultaneously therewith catalytically cracking a heavier hydrocarbon oil in the presence of a powdered cracking catalyst comprising a siliceous material which is diierent from the dehydrogenatlng catalyst, combining products of reaction from both conversion steps, subjecting the mixture to continued conversion in the presence of the mixed dehydrogenating and cracking catalysts, separating vaporous conversion products from nonvaporous liquid residue containing the mixed catalysts, fractionating said vaporous conversion products to separate fractionated vapors in the gasoline boiling range from higher boiling conversion products and returning said higher boiling conversion products to the second mentioned conversion step.

4. A process for the production of high antiknock gasoline, which comprises catalytically reforming a, relatively light oil in the presence of a powdered dehydrogenating catalyst, simultaneously therewith catalytically cracking a heavier hydrocarbon oil in the presence of a powdered cracking catalyst comprising a siliceous material which is different from the dehydrogenating catalyst, combining products of reaction from both conversion steps, subjecting the mixture to con- Y tinued conversion in the presence of. the mixed dehydrogenating and cracking catalysts, separating vaporous conversion products from nonvaporous liquid residue containing the mixed catalysts, fractionating said vaporous conversion products to separate fractionated vapors in the gasoline boiling range from higherboillng conversion products.' returning said higher boiling conversion products to the second mentioned conversion step, cooling and condensing said fractionated vapors, collecting resultantl distillate and gas and returning at least a portion of said gas to the 'rst and second mentioned conversion steps.

GUSTAV E GIDFF.

Images