Manufacture of Liquid Sulphur Dioxide

Fifty years ago the world production of liquid sulphur dioxide was less than 1,00,000 tons. Over the past few decades use of sulphur dioxide in petroleum refining as solvent, in manufacture of paper pulp, in textiles as sulphites, bisulphites and hydrosulphites and in effective control of fermentation in wine making and as preservative for fresh fruits and vegetable has increased the demand many fold. 

Liquid sulphur dioxide finds occasional use as a refrigerating liquid for the manufacture of ice and as a solvent for the extraction of fats and oils from bones and other waste animal matter. It is also employed in the refining of natural petroleum, owing to its property of dissolving aromatic and other heavy hydrocarbons which are present in petroleum distillates.1 When the distillate is shaken with liquid sulphur dioxide at a low temperature, separation into two layers occurs, one of which is the sulphur dioxide solution, the other the purified distillate containing paraffin hydrocarbons and naphthenes, which remain unaffected. 

Techno Economic Evaluation of Processes Involved to Manufacture Liquid Sulphur Dioxide and Liquid Sulphur Trioxide... 

This process is stiU in use in India in some of existing manufacturing units. However, the cost of production being high these are being replaced by latest technique of producing liquid Sulphur dioxide using molten Sulphur and liquid SO3. 

The liquid chromatographer, at the first thought of such a system, may well be dismayed at the problems of toxicity and mechanical handling that appears to accompany the use of such materials. However, in the early days of refrigeration, entirely sealed systems were manufactured successfully for use in domestic environments employing both ammonia and liquid sulphur dioxide as the refrigerating liquid. It follows that the development of sealed LC systems incorporating such materials for use by scientists in a laboratory environment appears distinctly possible. 

An electrolytic method for the manufacture of cupric sulphate depends on the electrolysis of a solution of sodium sulphate, using copper electrodes, and passing a current of carbon dioxide through the liquid. The copper dissolves at the anode, and is precipitated as carbonate at the cathode. The carbonate is subsequently dissolved in sulphuric add.1... 

The cold process for manufacturing sulfuric acid is, in turn, based on the cold process for sulfur dioxide. The cold process for sulfur dioxide is described in detail in the Appendix in a paper entitled Ashar NG (1999) Liquid sulfur dioxide without compression or refrigeration presented by one of the authors in Calgary (Canada) (1999) at a conference organized by British Sulphur. 

Mathieu, L. 1910. The determination of sulfurous acid. Ann.fals. elfraudes 3,410-415. Mathieu, L. 1913. Liquide sulfure dioxide in fermentation. Rev. vUicwUe 41, 421-428. Maxwell, F. 1916. Sulphitation in White Sugar Manufacture. N. Roger, London. May, P. 1927. The determination of sulphur dioxide in dried fruit. Analyst 62 (614), 271-273. 

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