GB742258A - Process for the production of salts and other compounds of metals - Google Patents

Abstract

Calcium and sodium oxalates are prepared by reacting carbon dioxide with amalgams of the respective metals under anhydrous conditions the surface of the amalgam being continuously disrupted by the action of high speed brush or scrapers, preferably scraping the amalgam against the reactor wall. In an example 0.1 per cent sodium amalgam was reacted with dry carbon dioxide at 20 DEG C. while being continuously disrupted by a brush disc rotating at 1000 r.p.m. having resilient steel arms. The carbon dioxide was previously dried by sodium hyposulphite and yellow phosphorus and was oxygen free. When the reaction was complete distilled water was added in the absence of air whilst stirring and the aqueous oxalate solution recovered. Specification 491,879 [Group III], is referred to.ALSO:<PICT:0742258/III/1> Compounds of metals are formed by reacting a metal amalgam under anhydrous conditions with a gaseous reactant whilst rapidly and continuously disrupting the surface of the amalgam with a brush or scraper moving at high speed, preferably such as to brush or scrape the amalgam against the wall of the reactor. Reactions specified are the production of potassium or zinc hyposulphite by sulphur dioxide with potassium amalgam or zinc amalgam, and the peroxides of barium and sodium by reacting oxygen with the respective amalgams, but the process is stated to be suitable for reactions involving carbon monoxide, carbon dioxide, sulphur trioxide, sulphur dioxide, nitrogen peroxide, nitric oxide, chlorine peroxide, chlorine and oxygen. In the apparatus of Fig. 1 a resilient steel wire arm 1 rotating on spindle 2, scrapes the wall of the reactor 4 to which amalgam is fed by line 5. The gaseous reactant is fed through the hollow spindle 2 and channels 3 and the reaction products and gases are evacuated through a channel 6 closed by gate 8. Alternatively the brush or scraper 1 may take the form of a spiral brush working in a cylinder. The reactions are preferably effected in the absence of oxygen, unless it be a reactant, and it is further desirable when possible to extract the reaction product from the amalgam under anhydrous conditions Specification 481,879 is referred to.