Method for separating suspended solid materials from aqueous systems with colloidal flocculants
AssigneesFraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V., Leibniz-Institut FüR Polymerforschung Dresden E.V.
InventorsWerner Jaeger, Bernd-Reiner Paulke, Simona Schwarz, Mandy Mende
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Abstract
The invention relates to a method for separating suspended solid materials from aqueous systems, in which the latter is mixed with a flocculant made of polymer colloidal particles with cationic surface charge and subsequently the flocculated material is separated from the aqueous system.
Claims13
A method for separating suspended solid materials from an aqueous medium comprising mixing the aqueous medium with a flocculant made of a polymer colloidal particles with cationic surface charge to obtain a flocculated material and subsequently separating the flocculated material from the aqueous medium, wherein
- the colloidal particles are formed by emulsion copolymerisation of one or more hydrophobic vinyl monomers with one or more cationic vinyl monomers,
- wherein the emulsion copolymerisation is implemented in a feed method wherein the one or more cationic vinyl monomers are fed in a continuous manner,
- wherein the charge density of the colloidal particles is from 5 μC/cm2 to 35 μC/cm2 and the size of the colloidal particles is from 50 nm to 1,000 nm, and wherein the one or more hydrophobic vinyl monomers are styrene and/or a homologue thereof, the one or more cationic vinyl monomers are N-methacryloyloxyethyl-N,N,N-trimethylammonium chloride, N-methacryloyloxyethyl-N,N-dimethyl-N-benzylammonium chloride and/or 4-vinylpyridine, and the cationic surface charge is bonded to the particle surface directly or via a spacer.
A method for separating suspended solid materials from an aqueous medium comprising mixing the aqueous medium with a flocculant made of a polymer colloidal particles with cationic surface charge to obtain a flocculated material and subsequently separating the flocculated material from the aqueous medium,
- wherein the colloidal particles are formed by emulsion copolymerisation of one or more hydrophobic vinyl monomers with one or more cationic vinyl monomers,
- wherein the charge density of the colloidal particles is from 5 μC/cm2 to 35 μC/cm2 and the size of the colloidal particles is from 50 nm to 1,000 nm, and wherein the one or more hydrophobic vinyl monomers are styrene and/or a homologue thereof, the one or more cationic vinyl monomers are N-methacryloyloxyethyl-N,N,N-trimethylammonium chloride, N-methacryloyloxyethyl-N,N-dimethyl-N-benzylammonium chloride and/or 4-vinylpyridine, and the cationic surface charge is bonded to the particle surface directly or via a spacer.
Dependencies are inferred from the claim text.