Abstract: The process of making N,N-dimethyl-N-alkylamines containing less than 1% of alkanols by hydrogenation of N,N-dimethylalkylamines on a catalyst of the copper chromite type containing an amount of manganese oxide effective to keep the alkanol level below 1%.

Abstract: The present invention provides grafted ethylene copolymers usable more especially as additives for inhibiting the depositions in crude oils.Said copolymer being formed of ethylene and at least one monomer with ethylenic unsaturation, chosen from vinyl esters of C.sub.2 to C.sub.18 monocarboxylic acids, the alkyl esters in the C.sub.1 to C.sub.12 range of unsaturated monocarboxylic acids from the C.sub.3 to C.sub.12 range and the .alpha., .beta.-unsaturated dicarboxylic compounds, on which are fixed the grafts of a homo or copolymer of an .alpha., .beta.-unsaturated monocarboxylic acid ester with at least one alkanol of a chain length equal to or greater than C.sub.12 and at least 20% of which is of a chain length equal to or greater than C.sub.22. Such copolymers may be used more especially as additives for inhibiting the deposition of paraffins and for improving the flow properties of the crude oils.

Abstract: The present invention relates to novel mixtures based on fatty diamines used for the preparation of surface active agents intended for the preparation of emulsions of hydrocarbon binders, wherein the fatty diamines of said mixtures have the formula: ##STR1## in which R is a saturated or non-saturated alkyl radical having from 8 to 22 carbon atoms, and 2.ltoreq.n.ltoreq.6.

Abstract: A hydrocarbon feedstock derived from crude oil or other sources is subjected continuously to thermal cracking under pressure and in the presence of hydrogen in order to convert the feedstock to products of lower molecular weight containing high proportions of olefinic components. In a first processing step, a catalytic hydrogenating pretreatment is performed at a temperature within the range of 300.degree. C. to 600.degree. C. and under a pressure within the range of 12 to 85 bars. In a second step, a thermal cracking treatment is performed under a pressure within the range of 10 to 70 bars with residence times of less than 0.5 second and at a temperature within the range of 625.degree. C. to 1,000.degree. C., the quantity of hydrogen employed being such that the molar concentration in the effluents is at least equal to 20%.