Carboxylic acid

About: Carboxylic acid is a research topic. Over the lifetime, 48544 publications have been published within this topic receiving 605696 citations.

Photodegradation of toluene over TiO2−xNx under visible light irradiation

Abstract: We report the photooxidation of toluene over nitrogen doped TiO2 (TiO2−xNx) under visible light irradiation. The photocatalytic oxidation of toluene in air over TiO2−xNx powders was studied using diffuse reflectance Fourier transform infrared spectroscopy (DRIFTS), gas chromatography (GC), ion chromatography (IC), and gas chromatography mass spectrometry (GC-MS), focusing on the photocatalytic decomposition processes of toluene. Results obtained indicate that toluene, weakly adsorbed on the catalyst surface, is initially photooxidized to benzaldehyde which adsorbs onto the TiO2−xNx surface more strongly, leading to the formation of ring-opening products such as carboxylic acids and aldehydes. No gaseous intermediates were detected during the photooxidation. Major intermediates adsorbed at the catalyst surface were oxalic acid, (COOH)2, acetic acid, CH3COOH, formic acid, HCOOH, and pyruvic acid, CH3COCOOH, whereas more complicated carboxylic species, including propionic acid, CH3CH2COOH, isovaleric acid, (CH3)2CHCH2COOH, and succinic acid, (CH2COOH)2, were also found in the early stage of the photooxidation. These intermediate products were gradually photodegraded to CO2 and H2O under visible light irradiation.

Polymerication processes and products therefrom

Abstract: 1. In a process for preparing a cation exchange resin having a water-insoluble matrix and cation exchange groups bonded thereto, the improvement comprising employing as said matrix a solid copolymer of macroreticular structure which is permeated by small channels or voids into which liquids are able to penetrate, which matrix is prepared by copolymerizing a mixture consisting essentially of (1) a monovinyl carbocyclic aromatic compound or an ester of acrylic or methacrylic acid, with (2) a polyethylenically unsaturated monomer selected from the group consisting of a polyvinyl carbocyclic aromatic compound, an ester of a dihydric alcohol and an α-β-ethylenically unsaturated carboxylic acid, diallyl maleate, and divinyl ketone; the aforesaid copolymerization being conducted while the monomers are dissolved in 25 to 150% by weight, based on monomer weight, of an organic liquid or mixture of organic liquids which is a solvent for said monomers but is unable to substantially swell the copolymers resulting from copolymerization.

Polymers useful as pH responsive thickeners and monomers therefor

Abstract: Novel aqueous thickener or thixotropic polymers are prepared by the copolymerization of (A) about 15-60 weight percent of a C 3 -C 8 alpha, beta-ethylenically unsaturated carboxylic acid monomer, preferably acrylic or methacrylic acid or a mixture thereof with itaconic or fumaric acid, (B) about 15-80 weight percent of a nonionic copolymerizable C 2 -C 12 alpha, beta-ethylenically unsaturated monomer, preferably a monovinyl ester such as ethyl acrylate or a mixture thereof with styrene, acrylonitrile, vinyl chloride or vinyl acetate, and (C) about 1-30 weight percent of a new and novel nonionic ethylenically unsaturated nonionic biphillic monomer such as tristyrylpoly(ethyleneoxy) x methyl acrylate, to provide a stable aqueous colloidal dispersion at an acid pH lower than about 5.0 but becoming an effective thickener for aqueous systems upon adjustment to a pH of about 5.5-10.5 or higher. These polymers adjusted to a pH of about 5.5 or higher are effective thickeners for a wide variety of aqueous systems including cosmetic products, drilling muds, aqueous coating compositions such as latex paint, and high solids compositions such as spackle, grouts, cements, and the like.

Extraction equilibria of organic acids with tri-n-octylphosphineoxide

Abstract: The extraction equilibrium of organic acids (acetic, glycolic, propionic, lactic, pyruvic, butyric, succinic, fumaric, maleic, malic, itaconic, tartaric, citric and isocitric) with tri-n-octylphosphine oxide (TOPO) was measured. The solvation numbers of the acids were the same as the numbers of the carboxyl groups on each acid molecule. The extraction equilibrium constant was controlled by the hydrophobicity of the acid when hexane was used as a diluent.