Showing papers on "Sodium hypophosphite published in 1977"

Method for waste recovery from a process of the production of diphenylolpropane

Abstract: The essence of the invention consists in heating the dian waste in the presence of sodium hypophosphite as a catalyst in amount of 001 - 05% by weight at a temperature of 150 to 250° C and under reduced pressure in the range of 5 to 50 mm Hg As a result a destillate is obtained containing as main components phenol, o- and p-isopropenyl-phenol and their dimers at yield of about 40-74% by weight calculated in relation to the initial amount of dian waste The distillate obtained was made up with fresh phenol or with phenol and acetone and brought into contact with strongly acid cation exchanger, such as Wofatit KPS, Zerolit 225, Wofatit OK-80, in consequence the o- and p-isopropenylphenol and their dimers reacted with phenol to obtain the dian, the latter being then separated by known methods

Method of making a magnetic powder

Abstract: A method is provided for making a magnetic powder composed principally of cobalt from a mixture solution containing metal salts, such as cobalt salt, and the like, catalysts, such as palladium chloride, and the like, and reducing agents, such as sodium hypophosphite, and the like. Protein, such as albumin or hemoglobin, is added to the mixture solution to promote dispersion of cobalt particles therein. The magnetic powder thus obtained is suitable for use in the production of audio and video tapes.

Electro-deposition of a nonmagnetic conductive coating for memory wire protection

Abstract: Plated memory wire is provided with a nickel-phosphorous alloy protective coating through an electro-deposition process. The protective coating is electrically conductive, nonmagnetic and has a bright surface amenable to good solder bonding. The memory function is provided by a Saccharin-type nickel-iron-cobalt film and the protective overcoating is applied by submerging the wire in an electrolyte bath composed of 360 g/l of nickel sulfate (NiSO 4 .6H 2 O), 80 g/l of sodium sulfate (Na 2 SO 4 ), 60 g/l of sodium hypophosphite (NaH 2 PO 2 .H 2 O) and 25 g/l of boric acid (H 3 BO 3 ). The static bath is maintained at room temperature and the wire is moved through it at approximately eighteen inches per minute. An electro-deposition current density of from 20 to 80 ma./cm. 2 of plating area is employed.

Electrolyzer for solution of salt

Abstract: PURPOSE:To provide a multielectrode type electrolyzer of improved construction and functions, which is useful for the production of sodium hypophosphite by electrolyzing seawater or a solution of salt.

Eliminating and recovering nickel from aq. effluent - by boiling with sodium hypophosphite and catalyst such as palladium chloride

Abstract: A process for eliminating and recovering Ni from aq. effluent solns. comprises treating the solns. with sodium hypophosphite, using agitation at about boiling point maintaining the pH at 9-11, in the presence of at least 0.2 mg/l. of a catalyst selected from alkaline earth metal oxides and Gp. VIII metal chlorides. The process, which is simple and effective, recovers the Ni in an easily separable form, which is easy to reuse. The specified temp. is 90-100 degrees C and the specified catalysts is palladium chloride.

Production of electrically conductive paths on an insulating substrate

Abstract: this process applies to printed circuits obtained by the imagewise deposition of nickel using a procedure such as that described in U.S. Pat. No. 3,853,589 followed by electroless copper plating onto the nickel pattern. We have found that by depositing the nickel before the copper, as compared with direct deposition of the copper, gives less deposition on the areas between the conductive paths and hence better insulation between them.The process can be performed in five stages including (a) coating a substrate, for instance by a gravure technique, with an active agent including a water-soluble quaternized bipyridilium compound, e.g. N,N'-dimethyl-4,4'-bipyridilium dimethosulphate or N,N'-bis(4-cyanophenyl)4,4"-bipyridilium dichloride and a suitable binder therefore such as polyvinyl alcohol, (b) imagewise exposing the coating where the conductive paths are to be deposited to sensitizing radiation, (c) contacting the surface with a solution of palladium chloride in hydrochloric acid, preferably containing 0.5 to 0.15 g/l PdCl2, (d) contacting the substrate with an aqueous electroless nickel plating bath, preferably at pH 8 to 9, and (e) contacting the substrate with an electroless copper plating bath.Further reduction in the metal deposition between the conductive paths is obtained by contacting the surface of the substrate with an aqueous solution of a reducing agent such as sodium hypophosphite between steps (c) and (d), rubbing the surface of the substrate between steps (d) and (e), or both procedures.

Reduction of thallium(III) by sodium hypophosphite in aqueous solution in the presence of certain complexones

Abstract: 1. The authors have used spectrophotometry to study the kinetics of the reduction of thallium(III) by sodium hypophosphite in the presence of nitrilotriacetic acid, ethylenediaminetetraacetic acid, and diethylenetriamine pentaacetic acid. 2. Addition of complexones to a solution of thallium(III) makes it more resistant to reduction by H2PO2− and increases the activation energy of the reaction.

Vanadometric estimation of germanium

Abstract: Germanium is determined titrimetrically using sodium vanadate as the oxidant, after reducing Ge(IV) to Ge(II) by sodium hypophosphite. Germanium in presence of the associated elements like zinc, cadmium, arsenic and silver as well as in the synthetic mixture of germanium-cadmium sulphide has been estimated.