GB666206A - An improved process for neutralizing capillary active, sulphonated products - Google Patents

Abstract

A process for neutralizing sulphonated mono-or diglycerides of higher fatty acids having at least 8 carbon atoms in the molecule, is characterized by adding the crude sulphonation product to an inert organic solvent for the sulphonation product in which solvent there is suspended a neutralizing agent slightly soluble or insoluble in the said solvent. The crude sulphonation product is applied to the suspension of the neutralizing agent in the form of a thin jet. Any organic solvent may be used which does not react in an undesirable way with the sulphonating agent under the neutralizing conditions, for example aliphatic alcohols such as methyl alcohol, ethyl alcohol, propyl alcohols, butyl alcohols and amyl alcohols, polyhydric aliphatic alcohols such as ethylene glycol and glycerols, ketones such as acetone and methyl ethyl ketone, ethers such as dimethyl ether, diethyl ether and diisopropyl ether, but ethyl and propyl alcohols are preferred. Hydrocarbons and halogenated hydrocarbons are suitable solvents but less satisfactory than the alcohols. Mixtures of solvents may be used. The organic solvents may contain water or water may be emulsified with water-immiscible organic solvents. As neutralizing agents may be used any substance of alkaline reaction and only slightly soluble or insoluble in the organic solvent, examples of which are the hydroxides such as calcium and magnesium hydroxide, oxides such as calcium and magnesium oxides and salts having an alkaline reaction such as phosphates or sulphites and carbonates and/or bicarbonates such as sodium carbonate, sodium bicarbonate, potassium carbonate, potassium bicarbonate, ammonium carbonate and ammonium bicarbonate. Preferably the neutralized sulphonated product should be soluble in the organic solvent and the neutralized sulphonated product should be precipitated together with unused neutralizing agent. The sulphonated product may be obtained from the solution by evaporation of the solvent after filtration though the latter is not essential. In the example a mixture of sulphonated coconut oil monoglycerides is poured as a thin jet into a suspension of sodium bicarbonate in ethanol. At approximately 25 DEG C. water formed by the neutralization will be absorbed by the sodium sulphate produced, which is insoluble in the alcohol.