GB491221A - Process for producing diesel oils - Google Patents

Abstract

Diesel oils are obtained by mixing (a) the paraffinic oils prepared by catalytic conversion of carbon monoxide and hydrogen with (b) liquid or solid carbonaceous products poorer in hydrogen. Suitable fractions under (a) are those boiling above 200 DEG C.; suitable products under (b) are pit-coal tar oils, brown coal tar oils, low temperature distillation oils, shale oils, wood tar and the like obtained by high or low temperature coking of pit-coal, brown coal, shale, wood, peat and the like, extraction products of pit-coal and brown coal, products of mild hydrogenation, and solid hydrocarbons. If the last are insoluble in the paraffinic hydrocarbons they are brought into solution or suspension by means of dissolving agents. The hydrogen content of the products poor in hydrogen should not be so low as to cause excessive precipitation on addition of the paraffinic hydrocarbons; in some cases it is desirable, prior to mixing, to treat the product poor in hydrogen with a small quantity of gas oil to precipitate the insoluble substances which are then separated off. The substances so precipitated can be hydrogenated to useful oils. Also, in some cases the product from which the precipitate has been removed may be subjected to mild hydrogenation prior to mixture with the paraffinic hydrocarbons. The final mixture may be treated with fuller's earth and/or lye. The constituents are preferably mixed in such proportions as to give a Diesel oil of density 0,84-0,86 and a solidification point of about -20 DEG C. In the examples, Diesel oils are produced from (1) pit-coal tar oil of density 1,09, and a synthetic paraffinic oil of density 0,76 and initial B.P. 200 DEG C.; (2) brown coal tar of density 0,907 and B.P. 200-300 DEG C., and a synthetic oil of density 0,77 and B.P. 200-310 DEG C.; (3) a pit-coal distillate of density 1,07 and B.P. 215-360 DEG C. and the synthetic oil of example 2; (4) a pit-coal low temperature tar fraction of density 0,991 and B.P. 200-320 DEG C. and the synthetic oil of example 2; (5) a dephenolated pit-coal low temperature tar fraction of density 0,996 and B.P. 200-320 DEG C. and the synthetic oil of example 2; (6) an incompletely hydrogenated brown coal oil of density 0,901 and B.P. 200-300 DEG C. and the synthetic oil of example 1; (7) a pit-coal first stage hydrogenation oil of density 0,974 and B.P. 200-320 DEG C. and the synthetic oil of example 2; (8) a liquefied extract obtained by mild hydrogenation of pit-coal and having a density of 1,028 and B.P. 200-320 DEG C., and the synthetic oil of example 2; and (9) a heavy anthracene oil, first purified by treatment with gas oil, and a synthetic oil of B.P. 200-310 DEG C.