Pennwalt Corporation

Atlantic Richfield Company

Atochem North America, Inc.

Gregory A Wheaton

David M Gardner

Ming N Sheng

Jar-lin Kao

Altaf Husain

Harold Shalit

Martin Nosowitz

A continuous method is provided for preparing alkanesulfonyl halides, particularly chlorides and alkanesulfonic acids in high yields without the formation of undesirable side-products, and without the net production of hydrogen chloride as a by-product. The method involves the continuous electrolysis of an alkanethiol (RSH) or dialkyl disulfide (RSSR') in an aqueous hydrochloric acid-containing solution, continuously removing the electrolyzed product mixture from the electrolysis zone, and recovering the alkanesulfonyl chloride (RSO.sub.2 Cl) or alkanesulfonic acid (RSO.sub.3 H) product from the mixture. The alkyl groups in the dialkyl disulfide (R and R') may be straight or branched chain, substituted or unsubstituted, have 1 to 20 carbon atoms, preferably 1 to 12 carbon atoms, and may be different, but are preferably the same. The aqueous hydrochloric acid-containing medium and any unreacted sulphur compounds may be recycled through the electrolysis chamber.

Preparation of alkanesulfonyl halides and alkanesulfonic acids

Alkanesulfonic acids and alkanesulfonyl chlorides, free of undesirable side products arising from side-chain chlorination, are prepared by oxidation with hydrogen peroxide of the corresponding alkanethiol, dialkyldisulfide or alkyl alkanethiolsulfonate mixed with aqueous hydrochloric acid.

Oxidation of thiols, disulfides and thiolsulfonates

A method for decolorizing color contaminated alkanesulfonic or arenesulfonic acids represented by Formula I:

Decolorization of alkanesulfonic and arenesulfonic acids

An ozone-containing gas is used for removing oxidizable odorous impurities and color from alkanesulfonyl chlorides.

Purification of alkanesulfonyl chlorides

Dialkanesulfonyl peroxide (RSO.sub.2 --O--O--O.sub.2 SR) is prepared in a continuous process by electrolyzing the corresponding alkanesulfonic acid at an elevated temperature (to keep the peroxide product in solution) in a continuous-flow electrolysis cell, removing the solution from the electrolytic cell, cooling the solution to precipitate the peroxide product, and recycling the supernatant alkanesulfonic acid back to the cell.

Continuous preparation of dialkanesulfonyl peroxide

Arsenic impurities are removed from anhydrous hydrogen fluoride by treating the hydrogen fluoride with elemental chlorine and anhydrous hydrogen chloride or a fluoride salt or both and then separating the purified anhydrous hydrogen fluoride, preferably by distillation, from the nonvolatile arsenic compounds.

Removal of arsenic from hydrogen fluoride

In the preparation of alkali metal chlorates, an aqueous alkali metal chloride is electrolyzed in the presence of at least one additive chosen from among silicates, fluorides, polybasic hydroxyalkanoic acids or their alkali metal salts, and sulfides. The use of such additives improves the power efficiency of chlorate production by eliminating the disadvantageous effects caused by the presence of transition metals.

Method for preparing alkali metal chlorates by electrolysis

In the process for oxidizing methacrolein to a methacrylic acid salt with an oxidizing gas in a strongly alkaline medium at a temperature of 0 to 100.degree. C. and in the presence of a finely divided silver catalyst and recovering methacrylic acid by acidification, the improvement which comprises carrying out said oxidation in the presence of a small amount of dissolved alkali metal carbonate.

Silver-catalyzed oxidation of methacrolein to methacrylic acid

A process for the preparation of a cyclic alkylene carbonate ester which comprises reacting in a liquid phase a cyclic or linear olefin having from 2 to 15 carbon atoms with carbon dioxide at a temperature of from 30.degree. to 160.degree. C., at a total pressure of from 100 to about 2,000 psig and a pH value of between about 4 and 8, in the presence of oxygen or an oxygen-containing gas and a catalytic amount of a mixture of (a) iodine or an iodide of a metal selected from Groups IA, IB, IIA, IIB, VB, VIIB and VIII of the Periodic Table of Elements, (b) a carbonate of a metal selected from Groups IB, IIA, IIB and VIII of the Periodic Table of Elements, (c) a catalytic iron compound and (d) a catalytic soluble cupric salt, and recovering resulting cyclic alkylene carbonate ester.

Preparation of alkylene carbonates from olefins

A process for the preparation of a cyclic alkylene carbonate ester which comprises reacting in a liquid phase a cyclic or linear olefin having from 2 to 15 carbon atoms with carbon dioxide at a temperature of from 50 to 160.degree. C., at a total pressure of from 200 to about 2,000 psig and a pH value of between about 4 and 8, in the presence of oxygen or an oxygen-containing gas and a catalytic amount of a mixture of (a) iodine or an iodide of a metal selected from Groups IA, IB, IIA, IIB, VB, VIIB and VIII of the Periodic Table of Elements and (b) a catalytic iron compound, copper compound of mixture thereof deposited on an inert supporting material, and recovering resulting cyclic alkylene carbonate ester.

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Logan Township, NJ, United States of America

Gregory A Wheaton