Patent GB-644873-A (GB)
Title: Production of polyolefinic hydrocarbons
IPC: C08F36/04
Filed: 1947-08-06
Abstract: Polyolefinic, polycyclic hydrocarbons produced by decomposition of a sludge containing non-aromatic hydrocarbon-hydrogen fluoride addition products (see Group IV (b)) are condensed with acid anhydrides or other derivatives, e.g. maleic, itaconic, and mesaconic anhydrides, and the products esterified or amidized to yield resinous and plastic materials.ALSO:Polyolefinic, polycyclic hydrocarbons are produced from a sludge composed of a complex addition product formed by reaction of non-aromatic hydrocarbons and hydrogen fluoride by subjecting it to catalytic decomposition at 50-200 DEG  C. in the presence of an inert hydrocarbon diluent boiling below about 150 DEG C. to decompose said complex product into a hydrogen fluoride vapour phase and a liquid phase comprising said polyolefinic hydrocarbons and at least part of said diluent.  An olefinic hydrocarbon of at least 4 carbon atoms, particularly a gasoline boiling from 30 DEG  to 250 DEG  C. formed by mixed polymerization of propene and butene, may be mixed with anhydrous HF, the proportion of HF to gasoline being 0.1-10 : 1 by weight, and the product separated into an upper hydrocarbon layer and a sludge phase.  The latter may be extracted with pentane to remove saturated hydrocarbons and then mixed with dried naphtha boiling at about 130-140 DEG  C., heated, and contacted with a decomposition catalyst to release HF and give a solution in naphtha of the desired hydrocarbons.  Metals, e.g. copper, aluminium, cobalt, lead, cadmium and brass, and non-activated carbons are suitable catalysts.  Other hydrocarbons used for sludge formation include branched paraffins, straight or branched mono- and poly-olefins or acetylenes, and cyclic olefins.  After drying, they are contacted with HF containing not more than 10 per cent water at about - 20 DEG  to 200 DEG  C. for not more than 2 hours.  Two mixers may be employed in series, the part-used HF separated from the hydrocarbon phase of the second being used in the first mixer, and fresh HF fed to the second mixer where it contacts the hydrocarbon phase separated from the product of the first.  The sludge may be treated in a settler and the sludge layer fed to an extractor having a leg into which pentane is fed just above the sludge outlet, and rises countercurrent to the sludge, extracting saturated hydrocarbons. After mixing with the diluent such as a paraffin of C5-C10 boiling at about 120-150 DEG  C., preferably in a proportion of 0.5-10 vols. naphtha per vol. of sludge, the sludge may be fed to a decomposition column.  An inert gas, preferably preheated to above the decomposition temperature, may be fed in at the bottom to strip the HF released.  The hydrocarbons obtained are alkali washed and fractionated to separate the polyolefinic product which may be further fractionated, usually at reduced pressure, to give a 300-400 DEG  C. fraction useful as a drying oil in paints and varnishes, a heavier fraction useful for coating compositions since it further polymerizes and oxidizes in air, and a light fraction boiling up to 300 DEG  or 325 DEG  C. which may be condensed with e.g. maleic, itaconic or mesaconic anhydride and esterified or amidized to give resins.  The polyolefinic hydrocarbons contain conjugated and additional non-conjugated unsaturation.  They may be mixed with natural drying oils or halogenated for use in insecticidal compositions.