Produits Chimiques Ugine Kuhlmann

Compagnie Europeenne Du Zirconium Cezus

Ugine Aciers

Jean G Guerin

Pierre Brun

Paul Besson

Michel Bakes

The process and the device according to the invention relate to the introduction, at a stable, known flow rate, of sublimable tetrachloride into a column for continuous extractive distillation under pressure of the chlorides. The sublimable tetrachloride is dissolved in a hot dissolver in a liquid solvent such as KAlCl.sub.4, and is then recirculated by pump at a stable, known flow rate into an evaporator connected to the column. The solution is then heated in an evaporator in order to sublime the majority of the product which it contains, the sublimed vapors thus passing into the column at a stable, known flow rate. The process according to the invention is adapted, in particular, to a plant for the production of ArCl.sub.4 of nulear purity and of HfCl.sub.4.

Process for introducing zirconium tetrachloride, hafnium tetrachloride

A method of preparing carbon tetrachloride of high purity from a crude mixture comprising lower aliphatic hydrocarbons, includes a step of liquid-phase chlorination at about 160.degree.-200.degree. C. and a step of vapor-phase chlorolysis at about 450.degree.-600.degree. C. in the presence of a metal chloride catalyst such as MoCl.sub.5. This method has both economic and anti-pollution advantages in the treatment of otherwise waste residues from the industrial manufacture of, for example, vinylchloride monomer, ethylene and propylene oxides or chloroprene. Carbon tetrachloride is an old product having known utilities as solvent for resins, waxes, lacquers and for dry cleaning; also as fire-extinguisher, extractor of seeds, anthelmintic in hookworms, exterminator of grain weevils, etc.

Method of preparing carbon tetrachloride

The invention relates to a process for the separation of zirconium, and hafnium tetrachlorides from mixtures thereof. The process according to the invention consists of selectively absorbing zirconium tetrachloride and hafnium tetrachloride vapors in a solvent medium circulating counter-current to these vapors in a distillation column, wherein the solvent consists of a molten chloroaluminate and/or chloroferrate of potassium. The process described may be used to obtain hafnium-free zirconium tetrachloride which may then be used to prepare nuclear-grade zirconium, and hafnium tetrachloride containing little zirconium.

Process for the separation of zirconium and hafnium tetrachlorides from

Perchloromethyl mercaptan is prepared with about 10% saving in raw materials by an improved process comprising (i) chlorinating carbon disulfide in the presence of iodine to produce a first chlorinated liquor, (ii) separating said liquor by distillation into a high-boiling fraction of technical-grade perchloromethyl mercaptan and a low-boiling fraction, A, (iii) chlorinating fraction A in the presence of iodine and absence of any substantial amount of metallic halides to produce a second chlorinated liquor, (iv) separating said second liquor by distillation into a high boiling fraction of crude perchloromethyl mercaptan and a second low-boiling fraction, B, consisting essentially of sulfur dichloride, and (v) heating fraction B at about 90.degree.-150.degree.C in presence of a metallic halide to form sulfur monochloride and regenerate chlorine.

Growing community of inventors

Grenoble, France

Jean G Guerin