C:Corrosive;
79-14-1Relevant articles and documents
Gas Evolution Oscillators. 2. A Reexamination of Formic Acid Dehydration
Smith, Kenneth W.,Noyes, Richard M.,Bowers, Peter G.
, p. 1514 - 1519 (1983)
At formic acid concentrations of about 0.3 M in warm concentrated sulfuric acid, carbon monoxide is evolved smoothly whether the solution is stirred or not.If such a solution is rapidly stirred, decay of formic acid obeys clean irreversible first-order kinetics.If the solution is not stirred, the concentration of dissolved carbon monoxide rises to a limit of about 0.07 M; this value is about 80 times the equilibrium solubility at 1 atm.In an unstirred solution, the system approaches a "pseudoequilibrium" in which the concentrations of dissolved HCOOH and CO are about equal.If the concentration of formic acid is increased to about 4 M, gas is evolved from a gently stirred solution in oscillatory pulses.The amount of gas evolved during a pulse decreases with successive pulses, the maximum change in dissolved-gas concentration being approximately 0.07 M per pulse.These observations indicate that the oscillations result from repetitive release of supersaturation by homogeneous nucleation; they invalidate the purely chemical explanation developed by Showalter and Noyes.Supersaturations of up to 80-fold suggest that formic acid in concentrated sulfuric acid can generate carbon monoxide in situ at concentrations that could otherwise only be attained with high-pressure apparatus.
Glycolic acid production using ethylene glycol-oxidizing microorganisms
Kataoka, Michihiko,Sasaki, Mie,Hidalgo, Aklani-Rose G.D.,Nakano, Michiko,Shimizu, Sakayu
, p. 2265 - 2270 (2001)
Screening for microorganisms oxidizing ethylene glycol to glycolic acid was carried out. Among stock cultures, several yeasts and acetic acid bacteria showed high glycolic acid producing activity. Pichia naganishii AKU 4267 formed the highest concentration of glycolic acid, 35.3 g/l, from 10% (v/v) ethylene glycol (molar conversion yield, 26.0%). Among soil isolates, Rhodotorula sp. 3Pr-126, isolated using propylene glycol as a sole carbon source, formed the highest concentration of glycolic acid, 25.1 g/l, from 10% (v/v) ethylene glycol (molar conversion yield, 18.5%). Rhodotorula sp. 3Pr-126 showed higher activity toward 20% (v/v) ethylene glycol than P. naganishii AKU 4267. Optimization of the conditions for glycolic acid production was investigated using P. naganishii AKU 4267 and Rhodotorula sp. 3Pr-126. Under the optimized conditions, P. naganishii AKU 4267 and Rhodotorula sp. 3Pr-126 formed 105 and 110 g/l of glycolic acid (corrected molar conversion yields, 88.0 and 92.2%) during 120 h of reaction, respectively.
Theoretical study of Al(iii)-catalyzed conversion of glyoxal to glycolic acid: Dual activated 1,2-hydride shift mechanism by protonated Al(OH) 3 species
Ohshima, Takashi,Yamamoto, Yoshihiro,Takaki, Usaji,Inoue, Yoshihisa,Saeki, Takuya,Itou, Kenji,Maegawa, Yusuke,Iwasaki, Takanori,Mashima, Kazushi
, p. 2688 - 2690 (2009)
Density functional theory calculations demonstrate that Al(iii)-catalyzed conversion of glyoxal to glycolic acid proceeds via a 7-membered dual Lewis acid-hydrogen bonding activation transition state of the 1,2-hydride shift, rather than the previously proposed 5-membered metal-alkoxide chelate activation transition state. The Royal Society of Chemistry 2009.
Facilitated series electrochemical hydrogenation of oxalic acid to glycolic acid using TiO2 nanotubes
Im, Sunmi,Park, Yiseul,Saad, Sarwar
, (2022/01/11)
In this study, the electrochemical reduction of oxalic acid (OX) was performed at electrodes made of TiO2 nanotubes (TNTs) in an aqueous medium under potentiostatic control in a two-compartment cell. The competing H2 evolution was almost non-existent at an applied potential of ?1.0 V vs Ag/AgCl. Thus, complete conversion of OX was achieved in high chemical (95%) and Faradaic (67%) yields. The selectivity of glycolic acid (GC) formation over that of glyoxylic acid (GO) is controlled by the length of the TNTs. A high selectivity (GC/GO ≈ 10) was obtained (glycolic acid/glyoxylic acid ≈ 10). The physical properties of the TNTs, such as length, uniformity, and mechanical strength, were controlled by varying the anodization time and the electrolyte composition.
PROCESSES FOR PREPARING ALDARIC, ALDONIC, AND URONIC ACIDS
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Paragraph 0113-0116, (2021/05/29)
Various processes for preparing aldaric acids, aldonic acids, uronic acids, and/or lactone(s) thereof are described. For example, processes for preparing a C2-C7 aldaric acid and/or lactone(s) thereof by the catalytic oxidation of a C2-C7 aldonic acid and/or lactone(s) thereof and/or a C2-C7 aldose are described.
Experimental and kinetic study of the conversion of waste starch into glycolic acid over phosphomolybdic acid
Dai, Hongqi,Qiao, Yongzhen,Wang, Xiu
, p. 30961 - 30970 (2021/11/19)
The starch used to enhance the paper surface dissolves in water during the production process and forms pollutants that accumulate in water when old corrugated cardboard (OCC) is returned to a paper mill for pulping and reuse. At present, anaerobic fermentation is widely used in the paper industry to treat starch-containing wastewater, producing biogas energy, or oxidative decomposition, which is a huge waste of valuable starch resources. Phosphomolybdic acid (PMo12) is a highly selective catalyst for the oxidation of carbohydrates; therefore, PMo12 can be envisaged as a suitable catalyst to convert waste starch into glycolic acid, an important high added-value chemical. In this paper, the catalytic oxidation technology of PMo12 was explored to produce glycolic acid from starch contained in OCC papermaking wastewater, and the kinetics and influencing factors of the catalytic oxidation reaction were studied. The results indicated that the PMo12-catalyzed oxidation of starch followed a first-order reaction; the reaction rate constant increased with increasing the temperature, the apparent activation energy of starch to monosaccharide was 104.7 kJ mol-1, the apparent activation energies of starch and monosaccharide to humins were 126.5 and 140.5 kJ mol-1, and the apparent activation energy of monosaccharide to glycolic acid was 117.2 kJ mol-1. The yields of monosaccharide and glycolic acid were 80.7 wt% and 12.9 wt%, respectively, and the utilization of starch resources was about 90.0 wt% under the following reaction conditions: temperature, 145 °C; reaction time, 120 min; pH, 2. Therefore, the feasibility of the PMo12-catalyzed oxidation of starch to produce high value-added glycolic acid is demonstrated, which has theoretical guiding significance and potential application value for the clean production and resource utilization of waste starch in the OCC papermaking process.
Homogeneous Reforming of Aqueous Ethylene Glycol to Glycolic Acid and Pure Hydrogen Catalyzed by Pincer-Ruthenium Complexes Capable of Metal–Ligand Cooperation
Zou, You-Quan,von Wolff, Niklas,Rauch, Michael,Feller, Moran,Zhou, Quan-Quan,Anaby, Aviel,Diskin-Posner, Yael,Shimon, Linda J. W.,Avram, Liat,Ben-David, Yehoshoa,Milstein, David
supporting information, p. 4715 - 4722 (2021/02/20)
Glycolic acid is a useful and important α-hydroxy acid that has broad applications. Herein, the homogeneous ruthenium catalyzed reforming of aqueous ethylene glycol to generate glycolic acid as well as pure hydrogen gas, without concomitant CO2 emission, is reported. This approach provides a clean and sustainable direction to glycolic acid and hydrogen, based on inexpensive, readily available, and renewable ethylene glycol using 0.5 mol % of catalyst. In-depth mechanistic experimental and computational studies highlight key aspects of the PNNH-ligand framework involved in this transformation.
Oxidative Conversion of Glucose to Formic Acid as a Renewable Hydrogen Source Using an Abundant Solid Base Catalyst
Takagaki, Atsushi,Obata, Wataru,Ishihara, Tatsumi
, p. 954 - 959 (2021/07/14)
Formic acid is one of the most desirable liquid hydrogen carriers. The selective production of formic acid from monosaccharides in water under mild reaction conditions using solid catalysts was investigated. Calcium oxide, an abundant solid base catalyst available from seashell or limestone by thermal decomposition, was found to be the most active of the simple oxides tested, with formic acid yields of 50 % and 66 % from glucose and xylose, respectively, in 1.4 % H2O2 aqueous solution at 343 K for 30 min. The main reaction pathway is a sequential formation of formic acid from glucose by C?C bond cleavage involving aldehyde groups in the acyclic form. The reaction also involves base-catalyzed aldose-ketose isomerization and retroaldol reaction, resulting in the formation of fructose and trioses including glyceraldehyde and dihydroxyacetone. These intermediates were further decomposed into formic acid or glycolic acid. The catalytic activity remained unchanged for further reuse by a simple post-calcination.
Electro-oxidation of glycerol into formic acid by nickel-copper electrocatalysts
Shen, Yi,Zhang, Jiali
, (2021/09/11)
Herein, non-precious metallic nickel-copper electrocatalysts were synthesized for electro-oxidation of glycerol in alkaline electrolytes. Activated carbon felt (ACF) is used as a supporting material because of its good conductivity, chemical inertness, and porous structure which is conducive to the transport of the reactants/electrons. The structural features of the catalysts were characterized by scanning electron microscopy, X-ray diffraction and X-ray photoelectron spectroscopy. The electrochemical activity of the catalysts was revealed by cyclic voltammetry, linear sweeping voltammetry, and chronoamperometry. The electrochemical results show that the Cu1Ni1@ACF catalyst possesses the highest current density of 1.31 mA cm-2 at 1.895 V. High-performance liquid chromatography results show that the as-prepared catalysts have high selectivities for formic acid (FA). Especially, the Cu1Ni1@ACF catalyst yields a selectivity of 97.4% for FA, which has so far been the largest value reported in the literature. Additionally, the effects of applied potentials and reaction time on product selectivity were studied.
The selective oxidation of glycerol over metal-free photocatalysts: insights into the solvent effect on catalytic efficiency and product distribution
Fan, Mingming,Haryonob, Agus,Jiang, Pingping,Leng, Yan,Yue, Chengguang,Zhang, Pingbo
, p. 3385 - 3392 (2021/06/06)
Selective oxidation of glycerol to high value-added derivatives is a promising biomass conversion pathway, but the related reaction mechanism, in particular the solvent effect, is rarely studied. In this work, O-doped g-C3N4was used as a metal-free catalyst to catalyze the selective oxidation of glycerol in different solvents. It was found that solvents can affect both catalytic efficiency and product distribution. A series of controlled experiments and theoretical calculation were applied to attest that the difference in interaction between glycerol and catalysts in different solvents is the main factor: competitive adsorption and hydrogen bond network from water inhibit the adsorption and activation of glycerol on the catalyst surface and reduce the conversion efficiency, while in acetonitrile, the stronger adsorption makes the oxidation reaction continue to yield esters. Two reaction routes in different solvents over O-doped g-C3N4are proposed for the first time, which is helpful for people to better understand the related reaction mechanism.
