Abstract: A process is disclosed wherein arsenic dissolved in wastewater or groundwater is removed from solution by precipitation thereof as calcium arsenate formed by the reaction of the arsenic with lime or hydrated lime in a heated solution at a pH of about 11 to about 13. It is preferred that the arsenic is first converted by oxidation to its pentavalent form.

Abstract: Particulates of a superabsorbent partially, neutralized acrylic polymer, e.g., polyacrylic acid, having a mean particle size ranging from 100 to 500 .mu.m, essentially monodisperse and essentially devoid of fines having a particle size of less than 100 .mu.m, having a nonuniformly surfaced spheroidal particle morphology and containing less than 50 ppm of residual monomer, well suited for a variety of hygienic applications, are prepared by (i) polymerizing a suspension of an acrylic monomer charge I in an organic medium and producing a suspension of acrylic polymer gel particles, (ii) next absorbing a second acrylic monomer charge II into the gel particles, (iii) polymerizing in the gel particles the second acrylic monomer charge II, (iv) azeotropically dehydrating the acrylic polymer particulates thus obtained, (v) then treating the dehydrated particulates with hydrogen peroxide, and (vi) drying the superabsorbent particulates thus treated.

Abstract: Catalytic compositions based on zeolite Y for use in the treatment of oxygenated effluents containing NO.sub.x, comprising 70 to 90% of zeolite NH.sub.4 Y having a specific surface between 750 and 950 m.sup.2 /g exchanged to cupric ions, wherein the copper content is between 2 and 12% relative to the weight of the zeolite; and 10 to 30% of a binder are disclosed. Processes for the preparation of such catalytic compositions are also disclosed.

Abstract: Thermoplastic compositions containing, per 100 parts by weight of a thermoplastic material containing at least one alkenyl aromatic hydrocarbon polymer or copolymer and, if required, at least one other thermoplastic of elastomeric resin:(a) from 5 to 30 parts by weight of melamine and melamine isocyanurate,(b) from 2 to 10 parts by weight of at least one polyol containing at least 4 hydroxyl functions per molecule, and(c) from 0 to 14 parts by weight of at least one organic ester of phosphoric acid.A process for their preparation consists of mixing the various constituents at a temperature higher than the softening point of the alkenyl aromatic hydrocarbon polymer or copolymer, between 150.degree. and 200.degree. C., for a duration between 1 and 5 minutes in an internal mixer or extruder.Articles obtained by transformation of the above compositions are formed having low combustion rates.

Abstract: Copolyamides having high crystallinity over the whole composition range, a melting enthalpy .DELTA.H>3.5 cal/g and a melting point T.sub.M higher than 270.degree. C. and articles manufactured therefrom are disclosed, said copolyamides comprising, by moles:a) 1 to 99% of a unit A of formula--(NH--R--NHCO--AR.sub.1 --CO)--in which R is a --(CH.sub.2).sub.n --carbon chain where n is coma) between 4 and 20, and AR.sub.1 is the residue from the condensation of terephthalic acid and/or of the diester form thereof; andb) 99 to 1% of a unit B of formula--(NH--R--NHCO--AR.sub.2 --CO)--in which R is the same carbon chain as in unit A and AR.sub.2 is the residue from condensation of naphthalene-2,6-dicarboxylic acid and/or the diester form thereof.

Abstract: Inclusion blocks of a substance chosen from ion exchange resins contaminated with radioactive elements, water which can, where appropriate, contain pollutants, solid-phase wastes in the form of blocks or pulverised preparations or liquid-phase wastes are prepared. For this purpose, the substances(s) to be included is/are embedded in a (meth)acrylic resin obtained in situ by direct polymerisation, without prior preparation of a prepolymer syrup, using a monomer system based on at least one (meth)acrylic monomer possessing a high boiling point, such as dicyclopentadienyloxyethyl methacrylate.Application to the storage of industrial pollutants, in particular substances contaminated with radioactive elements; and application of the water-inclusion blocks as prosthesis materials.

Abstract: A process for absorbing a water-soluble oil present as an aqueous emulsion in a cutting fluid which comprises contacting said cutting fluid with a composition containing at least one norborene polymer selected from polycyclo [2.2.1]-2-heptene or poly-5-methylbicyclo[2.2.1]-2-heptene, and at least one alkaline earth metal halide as an agent for breaking an aqueous emulsion of a water-soluble oil.

Abstract: Process for the removal of organic pollutants prevalent on a liquid or solid surface by sprinkling a polymer chosen from polybicyclo(2.2.1.) heptene-2 and polymethyl-5-bicyclo(2.2.1) heptene-2. The polymer is first agglomerated using a plasticizing agent. The process is used for the decontamination of water ways.

Abstract: This invention relates to novel reactive amino or hydrazino peroxides (hereinafter generally referred to as "AHP's") and derivatives all having a Structure A: ##STR1## in which the definitions of P, R11, R22, X, Q and x, y and z are given in the Summary Of The Invention section, for example, 4,4-di-(t-butylperoxy)pentanohydrazide (I-1), and the use of these novel compounds in curing unsaturated polyester resins, in initiating polymerization of ethylenically unsaturated monomers, for modifying rheology, for crosslinking and curing olefin polymers and elastomers, for producing novel graft and block copolymers, and for producing novel polymers with covalently bound performance additive functions.

Abstract: The invention relates to a catalyst comprising a rare metal of Group VIII of the Periodic Table of Elements which has been deposited on an inert support and which has been used to dehalogenate .alpha.-halogenated carboxylic acids in the presence of hydrogen, and a rare metal of Group VIII of the Periodic Table of Elements which has been deposited on an inert support and which is such that the granulometry of b) is very much lower than that of a) to form a homogeneous mixture as a result of the action of currents of .alpha.-halogenated carboxylic acid and hydrogen.It is particularly useful for regenerating palladium catalysts used in the purification of crude monochloroacetic acid.

Abstract: The invention relates to a process for the manufacture of 1,1,1,2-tetrafluorochloroethane and of pentafluoroethane.The process which consists of gas phase catalytic fluorination of at least one pentahaloethane of formula C.sub.2 HX.sub.2-n F.sub.3+n in which X denotes a chlorine or bromine atom and n the number 0 or 1, by hydrofluoric acid, is characterized in that a catalyst is employed consisting of a catalytic quantity of chromium in an oxidation state equal to or greater than 3 and of an activated charcoal as support.The selectivity for 1,1,1,2-tetrafluorochloroethane and pentafluoroethane reaches approximately 95% and even more.

Abstract: New and novel stabilized polymer compositions and processes for preparing them which employ new and novel carboxylic acid hydrazides bearing a 2,2,6,6-tetra-alkyl-4-piperidine ring and new and novel polymeric compositions stabilized therewith are provided.

Abstract: The acyl cyanides (nitriles), notably benzoyl cyanide, are prepared by reacting an acid halide with an alkali metal cyanide, in an anhydrous solvent medium, in the presence of an alkylene oxide compound and a polar compound other than water, e.g., glycerol, ethylene glycol, formamide or a sugar derivative.

Abstract: The acyl cyanides (nitriles) are prepared by reacting an acid halide with an alkali metal cyanide, in the presence of an alkylene oxide compound and a catalytically effective amount of water.

Abstract: To replace cleaning compositions based on 1,1,2-trichloro-1,2,2-trifluoroethane (F113), the invention provides a composition comprising, by weight, 30 to 69% 1,1,1,3,3-pentafluorobutane (F365-mfc), 30 to 60% methylene chloride and 1 to 10% methanol. These three compounds form a positive azeotrope (B.p.=32.1.degree. C. at normal pressure).The composition, optionally stabilized, can be used for the cleaning and/or the drying of solid surfaces, in particular for removing flux from printed circuits and for degreasing mechanical components.

Abstract: To replace cleaning compositions based on 1,1,2-trichloro-1,2,2-trifluoroethane (F113), the invention provides a composition comprising, by weight, 30 to 70% 1,1,1,3,3-pentafluorobutane (F365-mfc) and 70 to 30% methylene chloride. These two compounds form a positive azeotrope (B.p.=33.6.degree. C. at normal pressure).The composition, optionally stabilized, can be used for the cleaning and/or the drying of solid surfaces, in particular for removing flux from printed circuits and for degreasing mechanical components.

Abstract: The invention relates to high basicity polyaluminumchlorosulfates and their preparation process, said polyaluminumchlorosulfates being useful in the treatment of drinking water, aqueous effluents, and in the papermaking industry and having the formula:Al(OH).sub.a Cl.sub.b (SO.sub.4).sub.c M.sub.d N.sub.ein which:M is an alkaline-earth metal;N is an alkaline metal;a, b, c, d and e are numbers such that:1.95<a<2.4; 0<c<0.15; 0<d<0.16;0<e<1.7; a+b+2c=3+2d+e.

Abstract: In the process of removing heavy metals from aqueous solutions (groundwater) by precipitation of a salt thereof, an oxidizing agent is optionally used to increase the valence of said metal, and a precipitation-enhancing agent is added to maximize particle size of the precipitate and to facilitate its separation from said solution.

Abstract: Porous particles of MgCl.sub.2 which have essentially the shape of two truncated right cones connected by their larger bases, which truncated cones are incurved towards the axis of symmetry perpendicular to the bases, at the intersection of the envelope of the truncated cones with two orthogonal planes passing through the said axis of symmetry. These particles are impregnated with a transition metal compound and employed as a catalytic component in the polymerization of olefins. The resultant polyolefins, especially polyethylene, polypropylene and their copolymers, are comprised of particles with a distinctive structure.

Abstract: Polymer bound hindered amine light stabilizers are prepared by reacting hindered amine light stabilizers containing reactive hydrazide functionalities with anhydride containing polymers or copolymers. The reactions may be carried out in an inert solvent or in a melt blending step. The polymer bound hindered amine light stabilizers are useful alone or may also be used to stabilize other polymers, copolymers or polymers blends against the deleterious effects of heat and/or light.