Abstract: Particulate ore is pelletized by forming an intimate mixture with particulate binder in the presence of moisture, forming green pellets by agitation of the mixture and then firing these to produce ore pellets and the particulate binder comprises particles of a water soluble, partly cross-linked, polymer formed from water soluble, ionic, ethylenically unsaturated monomer or monomer blend, wherein the extent of cross-linking is insufficient to render the particles predominantly water insoluble but is sufficient to increase the dry strength of the ore pellets.

Abstract: A water absorbing particulate polymer material wherein the polymer material when in dry powder form has a particle size of about 50 .mu.m to about 500 .mu.m and wherein the particles consist of internally bonded finer particles which finer particles have a size below 50 .mu.m. The process of using the water absorbing polymer, material to convert a wet sticky mass of inorganic particulate such as coal fines into a crumbly or flowable solid. A process using a water absorbing particulate polymer material to convert a wet sticky mass of organic particulate material into a crumbly or flowable solid wherein the organic matter can be, for example, food waste or sewage.

Abstract: Particulate water-soluble or water-swellable polymeric material is provided with a substantially uninterrupted continuous coating of crystalline material. Single particles or aggregates having a size below 1 mm in size can be made by mixing the polymeric particles with a substantially saturated or supersaturated aqueous solution of crystallizable material (optionally a melt of hydrate crystallizable material) and thereby depositing it as a continuous crystalline coating on the particles.

Abstract: A liquid composition is disclosed which comprises a substantially stable dispersion in a liquid phase of particles comprising a detergent enzyme and a protective polymeric material that is impermeable to liquid detergent concentrates but releases the enzyme when agitated in aqueous wash liquor and comprises an outer polymeric shell and/or a polymeric matrix through which the enzyme is distributed.

Abstract: Polymeric compositions are stabilized against molecular weight degradation by the inclusion in the composition of an inhibitor which is preferably an ethylenically unsaturated compound. The invention is of particular value when the polymer is a polymer of (meth)acrylamide in which the amount of contamination of the polymer with free (meth)acrylamide monomer is extremely low and the inhibitor has LD.sub.50 above 400.

Abstract: Pellets of iron ore or other water insoluble particulate material are made from a mixture of the particulate material, moisture and a pelletizing binder by forming moist green pellets, a water displacing additive is applied to the surface of these pellets after they are substantially wholly formed, and the pellets are then dried. The preferred water displacing additive is a solution of a silicone in an organic solvent.

Abstract: High molecular weight polymer that can form a viscous aqueous solution is chemically modified by mixing the previously formed polymer (as a powder, reverse phase dispersion or oil-in-water emulsion) with water and the reagent for effecting the chemical modification so as to form a viscous aqueous mixture having a viscosity of at least 1OOO cps (Brookfield RVT) and then feeding this mixture as intermittent batches into one end of a tower through which it moves with substantially plug flow and from which it is withdrawn, at the end of the reaction, as intermittent batches. The apparatus for this purpose is also novel.

Abstract: A water absorbent water insoluble polymeric element, such as a fibre, film, coating, bonding layer or foam, is made by forming a substantially linear polymer by polymerisation of water soluble ethylenically unsaturated monomer blends comprising carboxylic and hydroxylic monomers and then reacting the carboxylic and hydroxylic monomers in the linear polymer to form internal cross links within the polymer.

Abstract: The use of very high molecular weight polymers which are substantially completely water soluble as flocculants in paper making improves drainage time without adversely affecting formation, even when used in high shear processes.

Abstract: Bentonite swelling clay is provided to a paper making mill as a fluid concentrate containing more than 15% bentonite wherein swelling of the bentonite is prevented by inorganic electrolyte in the concentrate, and the bentonite swells upon dilution either before addition of the cellulosic suspension or after addition.

Abstract: Water soluble polymerizable acrylic prepolymers can be formed from ethylenically unsaturated monomers that include monomers that provide a pendant group that is a blocked, saturated, ethylenic group, followed by unblocking the pendant saturated ethylenic group to leave a pendant ethylenically unsaturated group. These prepolymers can be copolymerized through these unsaturated groups, for instance after impregnation into a permeable substrate as in chemical grouting or shut off processes, to form cross linked solid polymers. The polymerizable monomers that are ethylenically unsaturated but which also include the blocked ethylenic group are also novel.

Abstract: Sewage sludge and other organic suspensions are prepared for filter press or belt press dewatering by substantially simultaneous treatment with a cationic coagulant polymer and a cationic flocculant polymer. A novel composition comprising a dry blend of the two polymers can then be formed to provide a combined solution for mixing with the suspension.

Abstract: A new process for producing allyl ethers, usually C.sub.8-30 alkyl (CH.sub.2 CH.sub.2 O).sub.5-100 allyl ether, by forming a solution of an alcohol, usually a surfactant alcohol, in a solvent capable of forming an azeotrope with water, azeotroping the mixture to remove substantially all the water, adding an alkalimetal alkoxide, usually sodium methoxide, removing the alkanol formed, usually by azeotroping with the solvent, adding a halide, usually allyl chloride, and recovering the allyl ether. The ethers are useful as monomers, for example to produce polymers by copolymerising with copolymerisable ethylenically unsaturated comonomers for a wide range of applications.

Abstract: Agrochemical and other particulate compositions are formed by coacervation. The coacervate is preferably formed from two water soluble coacervating polymers and stabilizes the particles against agglomeration. The coacervate is preferably formed from a relatively low molecular weight cationic polymer and a relatively high molecular weight anionic polymer.

Abstract: The use of very high molecular weight polymers which are substantially completely water soluble as flocculants in paper making improves drainage time without adversely affecting formation, even when used in high shear processes.

Abstract: An aqueous suspension of coagulatable material is coagulated by adding polymeric coagulant to the suspension and then separating the resultant coagulated material from the liquor. The coagulatable material may be present in the aqueous suspension as a suspension of suspended solids or as colloidally dispersed solids. The suspension may be coal tailings or other aqueous (generally mineral) suspension. The polymeric material must be a low molecular weight, highly ionic, polymeric material. It is added to the aqueous suspension while in the form of polymeric particles having a size mainly above 30 .mu.m and that will dissolve into the suspension and coagulate the coagulatable material. A counterionic, high molecular weight, flocculant is generally added subsequently in order to flocculate the coagulated material.

Abstract: Water absorbent particulate polymers and their uses are described. Friable aggregates may be made by bonding substantially dry polymer particles with an aqueous liquid and drying the aggregates. These aggregates can be broken down to the individual polymer particles upon mixing with an aqueous medium and thus can have the flow properties of relatively coarse particles and the performance properties of relatively fine particles. They may be soluble nd used as flocculants or viscosifiers or binders for, for instance, iron ore pelletisation. Alternatively they may be swellable and insoluble, for instance for converting a sticky particulate mass (such as coal fines filter cake) to a crumbly solid.

Abstract: A Bayer alumina recovery process is described in which lime is added at an intermediate or final wash stage of the red mud recovery circuit to improve flocculation, especially with flocculants having lower anionic content. The process is particularly useful with liquors containing high amounts of sodium carbonate and for process where the mud is settled by mud stacking.

Abstract: Suspended solids are separated from an aqueous suspension by mixing into the suspension first and second flocculants that would normally be incompatible in solution but which are added in the form of solids which dissolve into the suspension, and the resultant flocculated material is separated from the flocculated suspension.

Abstract: Particulate material such as iron ore is agglomerated into pellets or other agglomerates by being homogeneously mixed in the presence of moisture with a binder followed by agglomeration of the moist mixture, and the binder comprises a water soluble anionic polymer having intrinsic viscosity of from about 2 to about 7 dl/g and containing 5 to about 20% by weight carboxylic monomer groups (measured as sodium salt). The preferred polymer of is the copolymer of acrylamide and 5 to 20%, preferably 5 to 15%, sodium acrylate. The binder may also comprise bentonite.