Patent GB-994341-A (GB)
Title: Platy talc beneficiation
IPC: B03D1/012
Filed: 1961-06-23
Abstract: Talc is subjected to froth flotation to increase its content of platy talc by preparing an aqueous slurry, having a pH of 6.8 to 8 and a solids content of less than 30% by weight, of talc of particle size of 20 Tyler mesh or smaller and subjecting the slurry to froth flotation in the presence of at least 0.01 pounds per ton of solids of a synthetic organic wetting agent. Talc of enhanced platy talc content is recovered in the froth. The wetting agent may be cationic, anionic or nonionic amphoteric type and is preferably an alkyl sulphosuccinate.  Sulphosuccinates referred to are di-(1-methyl-4-ethylhexyl) sodium-, mono-2-ethylhexyl mono-1-metylheptyl sodium-, mono-2-ethylhexyl mono-1-methyl-4-ethylhexyl sodium-, di-(1-methylheptyl) sodium-, di-(2-ethylhexyl) sodiumdi-(1-isobutyl-3-methylbutyl) sodiumdi-(1-butyamyl) sodium-, di-(n-heptyl) sodium-, di-(n-octyl) sodiumdi-(1-methylhexyl) sodium-, sulphosuccinates, and mono-n-octadecyl di-sodium sulphosuccinate.  A small amount of a water soluble frother not exceeding 0.10 pounds per ton may also be added, suitable frothers being polypropylene glycol methyl ethers, ethyl alcohol, methyl alcohol or n-butyl alcohol; depressants such as starch, glue, dextrin or guar gum may also be added.  pH control may be effected with hydrochloric acid hydrobromic or nitric acid. The froth containing the platy talc may be finely passed to a thickener and thickened slurry recovered of a filter from which it is taken up in water to form a sprayable slurry which may be dried in suspension in hot gases at 300-900 DEG  F. Specification 961,194 is referred to.ALSO:Talc is subjected to froth flotation to increase its content of platy talc by preparing an aqueous slurry, having a pH of 6,8-8 and a solids content of less than 30% by weight, of talc of particle size of 20 Tyler mesh or smaller and subjecting the slurry to froth flotation in the presence of at least 0,01 pounds per ton of solids of a synthetic organic wetting agent. Talc of enhanced platy talc content is recovered in the froth. The wetting agent may be cationic, anionic or nonionic amphoteric type and is preferably an alkyl sulphosuccinate. Sulphosuccinates referred to are di-(1-methyl-4-ethylhexyl) sodium-, mono 2-ethylhexyl mono 1-methylheptyl sodium-, mono 2-ethylhexyl mono 1-methy-4-ethylhexyl sodium-, di-(1-methylheptyl) sodium-, di-(2-ethylhexyl sodium-, di-(1-isobutyl-3-methylbutyl) sodium-, di-(1-butylamyl) sodium-, di-(n-heptyl) sodium-, di-(n-octyl) sodium-, di-(1-methylhexyl) sodium-sulphosuccinates and mono n-octadecyl di-sodium sulphosuccinate.  A small amount of a water soluble frother not exceeding 0,10 pounds per ton may also be added, suitable frothers being polypropylene glycol methyl ethers, ethyl alcohol, methyl alcohol or n-butyl alcohol, depressants such as starch, glue, dextrin or guar gum may also be added.  pH control may be effected with hydrochloric acid, hydrobromic or nitric acid.  The froth containing the platy talc may be finally passed to a thickener and thickened slurry recovered of a filter from which it is taken up in water to form a sprayable slurry which may be dried in suspension in hot gases at 300-900  DEG F.