Abstract: Low molecular weight copolymers of the general formula: ##STR1## exhibit excellent concentrative action in the flotation of sylvinite ores thereby resulting in improved selectivity and recovery of sylvite (KCl). The low molecular weight copolymers perform concentrative action without resulting in any associated flocculation in the flotation process.

Abstract: Low molecular weight compolymers and terpolymers of the general structure: ##STR1## wherein R.sub.1 is hydrogen or a methyl radical, R.sub.2 is hydrogen or COOM and M is a hydrogen, alkali metal cation or ammonium ion, exhibit excellent depressive action in the flotation of non-sulfide mineral ores thereby resulting in improved selectivity and recovery. The low molecular weight copolymers and terpolymers, perform depressing action without resulting in any associated flocculation in the flotation system. These copolymers and terpolymers can be combined with other known depressing agents in nonsulfide ore flotation processes such as starch, dextrin, water soluble gum and the like, to obtain equivalent or improved selectivity and recovery than would be obtained using these depressants alone.

Abstract: Conventional starches are chemically crosslinked for use as selective depressants in the flotation of non-sulfide mineral ores. The process employing these crosslinked starches requires lower reagent dosages, exhibits improved selectivity and recovery and exerts a lower load on existing waste treatment facilities. The crosslinking agents employed are bifunctional and are used in sufficient quantities to result in 500 to 10,000 anhydroglucose units per crosslink.

Abstract: Low molecular weight hydrolyzed polymers or copolymers of the general structure: ##STR1## exhibit excellent depressive action in the flotation of non-sulfide mineral ores thereby resulting in improved selectivity and recovery. The low molecular weight, partially hydrolyzed polymers or copolymers perform depressing action without resulting in any associated flocculation in the flotation system. The partially hydrolyzed polymers or copolymers can be combined with other known depressing agents for non-sulfide ores, such as starch, dextrin, gum and the like, to obtain equivalent or improved selectivity and recovery than would be obtained using these depressants alone.

Abstract: Self-inverting emulsion polymers and their use as drainage aids, retention aids, saveall flotation aids and process water flocculants. The polymers are copolymers and homopolymers based on acrylamide, polymerized in the presence of water, an inert hydrophobic liquid, free radical catalyst and an emulsifier having a HLB of at least 7.