Patent GB-708254-A (GB)
Title: Improvements in or relating to the preparation of higher molecular weight alcohols and of olefins and detergent products therefrom
IPC: C07C303/24
Filed: 1950-11-03
Abstract: Higher alcohols are prepared by reacting C1-6 primary or secondary aliphatic or cycloaliphatic alcohols with C2-5 olefines or diolefines at temperatures between room temperature and 300 DEG  C. and at pressures between 50 and 2500 lb. per square inch gauge in the presence of a peroxide activator.  Molar ratios of alcohol to olefine of from 1 : 1 to 40 : 1 may be employed; preferably 1-5 parts by weight of alcohol per part of olefine are used at between 100 DEG and 300 DEG  C. and between 250 and 1500 lb. pressure.  Suitable peroxide activators are di-t-butyl peroxide, t-butyl hydroperoxide, benzoyl peroxide, cumene hydroperoxide, hydrogen peroxide, t-butyl perbenzoate, di-t-butyl perphthalate or per-adipate, acetyl peroxide, urea peroxide or mixtures of the same; these are used in amounts of 0.01-0.5 part per part of olefine and are preferably introduced portionwise.  Specified olefines are ethylene, propylene, the butylenes and pentenes, butadiene and isoprene; mixtures, e.g. of ethylene and propylene, may be used and saturates may be present. Alcohols mentioned specifically are methanol, ethanol, isopropanol, sec.-butanol, propyl methyl carbinol, isopropyl carbinol, butyl methyl carbinol, isobutyl methyl carbinol and cyclohexanol.  The reaction may be carried out batchwise or continuously.  Normally, the reaction is effected in an autoclave, the olefine being continuously fed in to maintain the selected reaction pressure.  The products obtained have a molecular weight not substantially in excess of 500. Ethylene gives rise to alcohols of the type R1R2C(OH).(C2H4)nH wherein R1 and R2 represent hydrogen atoms or alkyl groups which together contain not more than 5 carbon atoms or R1 and R2 together represent a cycloalkyl ring, and n varies from 1 to 18.  Mono-alkyl methyl carbinols react to yield 2-alkyl-2-alkanols, especially preferred being those of the type R.R1C(OH).CH3 where R is a straight chain C4-30 alkyl radical and R1 is a C1-4 alkyl radical.  The alcohols formed may be dehydrated to yield alkenes.  The 2-alkyl-2-alkanols form predominantly 2-alkyl-1-alkenes when the alkanols contain 7 or more carbon atoms and 2-alkyl-2-alkenes when they contain less than 7.  The dehydration may be effected by thermal or catalytic methods.  The 2-alkyl-2-alkanols dehydrate on heating to not substantially above 350 DEG  C. and contact agents such as solid phosphoric acid, clay, alumina or bauxite may be used. Isomerization occurs at the higher temperatures.  Dehydration is preferably effected by distilling the alcohol in the presence of a dehydrating agent such as the mineral acids, especially in the presence of an entrainer such as cyclohexane, isopropyl ether, t-butyl methyl ether, t-butyl ethyl ether, butyraldehyde, ethyl nitrate or certain aromatic hydrocarbons.  The alkenes R1R2.C = CH2 where R1 is a straight chain C4-30 alkyl radical and R2 is a C1-4 alkyl radical may be used in polymerizations, oxonations and alkylations; those which contain 7-36 carbon atoms may be used in the manufacture of synthetic lubricants, detergent-alkylates and oil-soluble sulphonates.  The alcohol products or fractions thereof may also be sulphated, e.g. by addition of an ethereal solution of oleum or chlorsulphonic acid to an ethereal solution of the alcohol, then diluting with cracked ice, neutralizing to pH 7 with caustic soda, washing with petroleum ether, diluting with isopropanol and desalting by addition of sodium carbonate. The products having 10-18 carbon atoms are detergents. Numerous examples are given, the following being typical: (1) ethylene is reacted in presence of di-tert.-butyl peroxide with methanol yielding primary alcohols, with isopropanol, cyclohexanol and sec.-butanol yielding tertiary alcohols and with ethanol yielding mixtures of secondary and tertiary alcohols, the products having molar weights of from 110 to 430; (2) in similar manner propylene is reacted with isopropanol and methanol respectively; (3) isobutylene is likewise reacted with isopropanol yielding higher alcohols including 2,4-dimethyl - 2 - pentanol and C11 tertiary alcohols, both being dehydrated over alumina to yield C1 and C11 olefines; (4) an isopropanolethylene condensate fraction obtained as in (1) and boiling at 125-165 DEG  C. is dehydrated over alumina to yield 2-methyl-heptene-1 and 2-methyl - heptenes -3, 4 and 5; another fraction B.P. above 200 DEG  C. is dehydrated in presence of sulphuric acid with cyclohexane as entrainer and yields 2-methyl-1-alkenes B.P. 180-468 DEG  C.; (5) an ethylene-ethanol condensate obtained as in (1) is fractionated and a C12-13 alcohol fraction is sulphated with chlorsulphonic acid; (6) a similarly obtained ethylene-methanol condensate fraction boiling at 285 DEG  C. is sulphated with oleum. Specification 583,181 is referred to.