GB584307A - Manufacture of preparations containing cupric oxychloride in a state of colloidal dispersion - Google Patents

Abstract

Cupric oxychloride preparations having a high content of colloidally-dispersed cupric oxychloride are produced by treating cupric chloride solution below 20 DEG C., advantageously between 0 DEG C. and 10 DEG C., with cupric oxide containing at least 4 per cent. water, a stabilizer, e.g., gelatine, glue or especially sulphite cellulose waste liquor optionally being incorporated in the resulting solution. In examples: (1) cupric chloride solution of 14.5 per cent. copper content is introduced during 3/4 hr. into dilute aqueous sodium hydroxide at 6-11 DEG C., the mixture being stirred thus for a further 1/2 hr. prior to heating at 85 DEG C. for 1/2 hr., maintaining the resultant precipitated copper oxide at 89 DEG C. for 5 mins. and washing, followed by addition, whilst moist, to a stirred aqueous cupric chloride solution kept at 2-7 DEG C. for 2 hrs. and stirred at room temperature for a further 18 hrs.; the product may be diluted with water to any extent to yield colloidal solutions. Alternatively, the copper chloride may be added to the cupric oxide, or the latter prepared from cupric sulphate, or the concentrations may be varied; (2) cupric chloride solution, containing 18 per cent. copper is introduced during approximately 1 hour into 30 per cent. sodium hydroxide solution maintained at 0-5 DEG C. and the resulting mixture is steam-heated to 83-85 DEG C. during 20-30 mins. and thus maintained for 25 mins., followed by rapid cooling to 70 DEG C. with added ice neutralization with hydrochloric acid, washing of the precipitated copper oxide at 50-60 DEG C. and subsequent addition, with ice, to a stirred cupric chloride solution kept below 7 DEG C., stirring being continued for 7 hrs. at 2-7 DEG C. and ultimately raising the temperature to 20-25 DEG C. during 5-6 hrs. and stirring for a further 6 hrs. to yield a product containing about 86 per cent. colloidal cupric oxychloride; (3) the product obtained as in (1) or (2) advantageously cooled to below 10 DEG C., is stirred with 47 per cent. sulphite cellulose liquor, stirring thus for an additional hour and for 2-3 hrs. at room temperature. The product may be diluted with hard water and is very insensitive to solutions of salt, e.g., sodium sulphate; (4) the aged product of (2) and a mixture of 47 per cent. sulphite cellulose liquor, 30 per cent. sodium hydroxide solution and water are simultaneously charged at room temperature into a stirring vessel when further similar charges are added uniformly, stirring being continued for 2-3 hrs. to yield a preparation having a degree of dispersion of about 64 per cent; (5) the preparation obtained as in (4) is stirred with a 5 per cent. methyl cellulose solution; (6) crystalline cupric chloride is introduced into a stirred mixture of cupric oxide, obtained as in (2), and ice-water; after stirring in an ice-bath for 6-7 hrs. stirring is continued for 18 hrs. at 10-15 DEG C. to yield a homogeneous green mass containing about 50 per cent. colloidal oxychloride. Specification 392,556 is referred to.