Abstract: A process for purifying a hydrogen peroxide solution is disclosed, comprising treating a 10 to 60% by weight hydrogen peroxide solution having a pH between 1.5 and 5.0 and containing anionic impurities with a hydrogencarbonate type or carbonate type anion exchange resin while adding an acid or a salt thereof having an acid dissociation constant pKa in water of not more than 5 to the hydrogen peroxide solution to be treated continuously or semi-continuously in an amount of from 0.5 to 5 milli-equivalents per liter of hydrogen peroxide solution. The hydrogen peroxide decomposing activity of the anion exchange resin can be inhibited without decreasing a rate of removal of strong acid radicals in the anionic impurities thereby minimizing oxygen evolution due to decomposition of hydrogen peroxide.

Abstract: A metallic ion sorber capable of absorbing ions of a metal excluding iron and cobalt and a method of sorbing ions of a metal excluding iron and cobalt are disclosed. The sorber comprises an ethylene copolymer containing from 40 to 95% by weight of ethylene and from 5 to 60% by weight of at least one of aminoalkyl acrylate compounds represented by formula: ##STR1## wherein R.sub.1 represents a hydrogen atom or a methyl group; R.sub.2 and R.sub.3 each represents an alkyl group having from 1 to 4 carbon atoms; and n represents an integer of from 1 to 4, and having a number average molecular weight of from 5,000 to 50,000.

Abstract: A metallic ion sorber capable of absoring ions of a metal excluding iron and cobalt and a method of sorbing ions of a metal excluding iron and cobalt are disclosed. The sorber comprises an ethylene copolymer containing from 40 to 95% by weight of ethylene and from 5 to 60% by weight of at least one of aminoalkyl acrylate compounds represented by formula: ##STR1## wherein R.sub.1 represents a hydrogen atom or a methyl group;R.sub.2 and R.sub.3 each represents an alkyl group having from 1 to 4 carbon atoms; andn represents an integer of from 1 to 4,and having a number average molecular weight of from 5,000 to 50,000.

Abstract: A uranyl ion selective electrode having a responsive membrane, an inner reference electrode, and a uranyl ion inner solution is disclosed, in which the responsive membrane is obtained by treating a membrane material with an ion-exchanger comprising at least one uranyl ion complex formed between a uranyl ion and a neutral phosphoric ester or a neutral phosphorous ester as a complexing agent, a diluent excellent in compatibility with the ion-exchanger, and a solvent mediator having affinity for the membrane material. The electrode is excellent in concentration responsiveness, reproducibility, accuracy, and durability and is particularly suitable for use in uranyl ion analysis in the atomic energy industry.

Abstract: A method for the removal of nitrogen oxides from heavy oil combustion exhaust gases containing nitrogen oxides, sulfur oxides and dusts by a catalytic reduction process using a moving catalyst bed reactor wherein the exhaust gases are catalytically contacted with ammonia at 250.degree. to 450.degree. C., which is characterized in that a sealing gas having a temperature of 200.degree. C. or higher, preferably 280.degree. C. or higher, and a pressure higher than the average pressure at the outlet and inlet of the moving catalyst bed reactor is introduced into the portions of the reactor where the catalyst is taken out therefrom and is again supplied thereto, whereby the decrease of the catalyst activity can be effectively prevented.

Abstract: A method for heat recovery in the processes of the removal of nitrogen oxides from exhaust gases containing sulfur oxides and nitrogen oxides by a catalytic or non-catalytic reduction thereof with ammonia. After passing through the reaction zone for the reduction of nitrogen oxides the down flow gases are subjected to the submitted air in a heat exchanger. The process is characterized in that the molar ratio of ammonia to sulfuric anhydride and the concentration of steam in the gases at the inlet of the heat exchanger is controlled in the range of O<NH.sub.3 /SO.sub.3 <2, preferably O<NH.sub.3 /SO.sub.3 <1.5 and more than 12% by volume, preferably more than 15% by volume, respectively, and thereby the process can continuously proceed without the production of ammonium sulfate and the deposition or adhesion thereof onto the surface of the various devices in the apparatus therefor.

Abstract: A method for removing nitrogen oxides from combustion exhaust gases obtained after removing sulfur oxides by a wet process, which is characterized in that the gases obtained after removing sulfur oxides from the combustion exhaust gases by a wet process are introduced into a wet electrostatic precipitator to remove most of the impurities such as dusts, fumes and mists, passed through a dummy catalyst layer in the form of a fixed bed or a moving bed to remove the remaining impurities which is set before or after heating the gases to a temperature suitable for the reaction of reducing nitrogen oxides, and passed through a metal oxides catalyst layer in the form of a fixed bed in the presence of ammonia which is used at least in the stoichiometric amount required for reducing nitrogen oxides to nitrogen gas by which the gases containing nitrogen oxides are reduced to harmless gases.