摘要:
An extraction process is described for the selective separation of metal ions belonging to the group Cu and Co, in aqueous solution of Cu- and Co-ions, wherein there is used as the extraction medium one or more unsaturated fatty acids, optionally in solution and/or in admixture with saturated fatty acids and an aliphatic oxime.
摘要:
An improved process for the manufacture of reinforced shaped articles from water-hardening materials. A plurality of continuous networks of synthetic organic polymer material having at least two meshes per square centimeter are incorporated in said water-hardening materials as reinforcement. The networks are prepared by forming meshes in an unfibrillated film of the synthetic organic polymer material.
摘要:
The invention relates to a method for removal of alkali metal carboxylates from mixtures which contain a cycloalkanone and a cycloalkanol, in particular cyclohexanone and cyclohexanol, and which have been obtained in oxidation in the liquid phase of the corresponding cycloalkane with gas containing molecular oxygen.According to the invention, alkali metal carboxylates are removed from such mixtures containing a cycloalkanone and a cycloalkanol by washing the mixture with an aqueous acid solution, in particular an aqueous solution of carboxylic acid with 1-6 carbon atoms per molecule.The invention provides a solution to the problem of the so-called alkali entrainment, which leads to loss of cycloalkanone owing to condensation into undesired high-boiling by-products in the following distillation for gaining pure cycloalkone. This substantial loss is prevented by the method according to the invention.
摘要:
The invention concerns a process in which a shaped article is prepared by first coating the inside of a mold with a coating powder, curing the coating, introducing a thermosetting mass in the mold and curing to form an article provided with a decorative layer. The invention consists in the use of a polyester-based coating powder, obtained by absorbing a liquid catalyst in part of the unsaturated components making up the powder, separately grinding that part and a mixture of the remaining components to about the same particle size and mixing the powders thus obtained. The invention assures better curing of the coating.
摘要:
Polypyrrolidone polymers and copolymers are obtained by polymerizing 2-pyrrolidone, optionally with another lactam, in the presence of a catalyst and accelerator, first in the mass until at least 10% of the monomer is converted but the reaction product is still capable of suspension, then completing the desired degree of polymerization by suspending the reaction mixture in an inert liquid dispersion agent that does not dissolve the desired polymer. Relatively high molecular weight polymers are prepared in a short amount of time using this two-stage procedure.
摘要:
2-pyrrolidones are prepared by hydrogenating a succinonitrile in the liquid phase in the presence of ammonia by passing an ammoniacal solution of a succinonitrile over a fixed bed catalyst, particularly of the trickle-phase type, in which the catalyst is nickel on an alkaline support such as calcium hydroxide or calcium carbonate. Attractive yields are achieved without the expense of filtering off and separating used catalyst as in prior procedures.
摘要:
A process is described for the recovery of 2-pyrrolidone monomer from polypyrrolidone waste material by heating the latter in the presence of a small amount of strong acid, and distilling off the said monomer.
摘要:
A process for removing melamine from liquids containing melamine by biological means. The aqueous solution or suspension of melamine is brought into contact with microorganisms or enzyme preparations having melaminase activity, and the resulting mixture is maintained under anaerobic conditions whereby at least a portion of the melamine is biodegraded.
摘要:
Single-component or two part polyurethane-based lacquers are prepared on the basis of a polymeric polyhydroxy compound having a high molecular weight in the range of 300 to 5000, such as poly(oxytetramethylene)glycol, a low molecular weight diol such as ethylene glycol, at least one isocyanate such as toluene diisocyanate and tris-(.beta.-hydroxypropyl)-isocyanurate or its ethoxylated derivative together with the customary accelerators, additives, solvents and the like used in lacquer manufacture. These lacquers exhibit exceptional hardness, high impact resistance, good adhesion to the substrate to which they are applied as well as corrosion resistance.
摘要:
Process for the preparation of a porous, pure silica which is particularly suitable as a catalyst support for a chromium-oxide catalyst used in polymerizing of olefins. The process comprises the steps of converting a silicon-halogen compound to a silica and then admixing with water to form a silica gel. The gel is then spray-dried to achieve the required particle size and pore volume.The silica can then be made into a catalyst by placing on the support a chromium compound and then heating in a non-reducing atmosphere.