Polyorganosiloxane collectors in the beneficiation of fine coal by froth flotation
AssigneeDow Corning Corporation
InventorsFook L. Ng, Bruce S. Higgs
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Abstract
A froth flotation process for the beneficiation of fine coal is disclosed which employs as a collector a water-dispersible polyorganosiloxane or a mixture of water-dispersible polyorganosiloxanes which contain either aryl radicals or aryl radicals combined with polyethylene oxide and polypropylene oxide radicals. Preferred polyorganosiloxanes are those which contain both aryl radicals and polyethylene oxide and/or polypropylene oxide radicals. The process of this invention is espeically useful for the beneficiation of difficult-to-float fine coals.
Claims34
A froth flotation process for the beneficiation of fine coal, which process comprises the steps of forming an aqueous slurry of the fine coal, adding a collector and a frothing agent to the aqueous slurry of fine coal, subjecting the aqueous slurry of fine coal containing the collector and frothing agent to froth flotation and separating the floated material which consists essentially of the beneficiated fine coal, wherein the collector is a water-dispersible polyorganosiloxane, or a mixture of water-dispersible polyorganosiloxanes, of the general formula
- R.sub.a Q.sub.b SiO.sub.(4-a-b)/2
- where a has an average value of 0 to less than four, b has an average value of greater than zero to less than four, the sum (a+b) has an average value of 0.9 to 2.7, R is a monovalent alkyl radical containing 1 to 20, inclusive, carbon atoms or a --OH radical, and Q is an aryl radical, attached to silicon through a Si--C bond, which is selected from the group consisting of phenyl, benzhydryl, benzyl, alpha-methylbenzyl, methylbenzyl, tolyl, phenethyl, alpha-methylphenethyl, and beta-methylphenethyl radicals.
A froth flotation process for the beneficiation of fine coal, which process comprises the steps of forming an aqueous slurry of the fine coal, adding a collector and a frothing agent to the aqueous slurry of fine coal, subjecting the aqueous slurry of fine coal containing the collector and frothing agent to froth flotation, and separating the floated material which consists essentially of the beneficiated fine coal, wherein the collector is a water-dispersible polyorganosiloxane, or a mixture of water-dispersible polyorganosiloxanes, of general formula
- Q.sub.c R.sub.(3-c) SiO[R.sub.2 'SiO].sub.n [R'QSiO].sub.m SiR.sub.(3-d) Q.sub.d
- where n has a value of 0 to 100, inclusive;
- m has a value of 0 to 70, inclusive;
- c and d are both independently equal to 0 or 1;
- the sum (m+c+d) is equal to or greater than 1;
- R is a monovalent alkyl radical containing from 1 to 20, inclusive, carbon atoms or a --OH radical;
- R' is a monovalent alkyl radical containing from 1 to 20, inclusive, carbon atoms;
- and Q is an aryl radical attached to silicon through a Si--C bond.
A froth flotation process for the beneficiation of fine coal, which process comprises forming an aqueous slurry of the fine coal containing a collector and a frothing agent, subjecting the aqueous slurry of the fine coal containing the collector and frothing agent to a froth flotation manipulation, and separating the tailing of the froth flotation manipulation from the floated material which consists essentially of the beneficiated fine coal wherein the collector is a water-dispersible polyorganosiloxane or a mixture of water-dispersible polyorganosiloxanes of general formula
- Q.sub.c R.sub.(3-c) SiO[R.sub.2 'SiO].sub.n [R'QSiO].sub.m SiR.sub.(3-d) Q.sub.d
- where n has a value of 0 to 100, inclusive;
- m has a value of 0 to 70, inclusive:
- c and d are both independently equal to 0 or 1;
- the sum (m+c+d) is equal to or greater than 1;
- R is a monovalent alkyl radical containing from 1 to 20, inclusive, carbon atoms or a --OH radical;
- R' is a monovalent alkyl radical containing from 1 to 20, inclusive, carbon atoms;
- and at least two different Q radicals are present where the first Q radical is an aryl radical and the second Q radical is selected from the group consisting of polyethylene oxide radicals and polypropylene oxide radicals where said Q radicals are attached to silicon through a Si--C bond.
Dependencies are inferred from the claim text.