Three-phase equilibrium conditions of hydrates (water-rich liquid, hydrate, and vapor) of carbon dioxide and methane binary mixtures were Investigated In the temperature range of 273-288 K and the pressure range of 1.2-11.0 MPa. The vapor-phase concentrations were measured by a gas chromatograph. The results obtained were In good agreement with previous measurements done by researchers at the University of Michigan who had calculated the carbon dioxide concentration In the vapor phase. The data obtained In this work did not show unusual hydrate phenomena, as reported In a more recent publication by researchers In Hungary.

The use of inorganic salts as catalysts for the reactions of D-glucose in aqueous solutions in a batch reactor is reported. The type of salt and effect of reaction time were examined in detail at a fixed salt (5 mM) and Dglucose concentration (0.1 M) and at a temperature of 140°C. Al(III) and Cr(II) salts gave the highest conversion of D-glucose. Typical reaction products were organic acids like lactic acid, levulinic acid, furanics like hydroxymethylfurfural and insoluble products (humins). The chemoselectivity is a clear function of the type of inorganic salt. For Al(III), the major water soluble product was lactic acid, for Zn(II) HMF was formed in the highest yields. A reaction scheme is proposed to explain the observed product compositions.

We herein present a study on the application of homogeneous catalysts in the form of metal salts on the conversion of trioses, such as dihydroxyacetone (DHA), and glyceraldehyde (GLY) to lactic acid (LA) in water. A wide range of metal salts (26 in total) were examined. Al(III) salts were identified as the most promising and essentially quantitative LA yields (>90 mol%) were obtained at 140 °C and a reaction time of 90 min. A reaction pathway is proposed and a kinetic model using the power law approach was developed for the conversion of DHA to LA with pyruvaldehyde (PRV) as the intermediate. Good agreement between experimental data and the model was obtained. Model predictions, supported by experiments, indicate that a high yield of LA is favoured in dilute solutions of DHA (0.1 M) at elevated temperatures (180 °C) and reaction times less than 10 min.

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A wide range of metal halides and triflates were examined for the conversion of D-glucose to HMF in DMSO. Chromium and aluminium salts were identified as the most promising catalysts. The effect of process variables like initial D-glucose concentration (0.1-1.5 M), reaction time (5-360 min) and reaction temperature (100-140°C) on the yield of HMF were examined at a fixed Al(OTf) 3 concentration (50 mM). Highest yields of HMF (60 mol%) were obtained using 1 M D-glucose (16 wt%), Al(OTf) 3 (5 mol%) at a temperature of 140°C. A reaction pathway involving initial isomerisation of D-glucose to D-fructose followed by a number of dehydration steps is proposed. Kinetic analysis reveals that the reaction is second order in D-glucose with an activation energy of 138 kJ mol -1 .

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Poly(o-aminobenzoic acid) and copolymers of o-aminobenzoic acid and aniline were synthesized as excellent candidates for the precursor of polyaniline. The reaction conditions were optimized with emphasis on the isolated yield. The polymers were characterized by a number of techniques including infrared spectroscopy, ultraviolet-visible spectroscopy, X-ray photoelectron spectroscopy, thermal analyses, and scanning electron microscopy. The yield of poly(o-aminobenzoic acid) was remarkably improved by addition of sodium hydroxide (an equivalent mole amount to the monomer) into the reaction system. Spectroscopic results indicate that the polymer has principally an Emeraldine structure. The copolymers were also obtained at high yield by addition of sodium hydroxide (an equivalent mole amount to o-aminobenzoic acid). The polymerization mechanism was briefly discussed on the basis of the pH effect upon the yield and easy elimination of the carboxyl group via a ring structure. The copolymer as well as poly(o-aminobenzoic acid) were found to be the precursors to produce polyaniline with elimination of carbon dioxide by heat treatment.

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