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Absorption of carbon dioxide (CO2) by blended diethanolamine (DEA) + 2-amino-2- methyl-1-propanol (AMP) and single DEA solvents were compared using hollow fiber membrane contactor (HFMC). Experimental results showed AMP additive has positive influence to improve CO2 absorption flux and the optimum AMP/DEA mass concentration ratio is between 0.2 and 0.4. Decreasing gas liquid ratio could greatly promote CO2 absorption, and operating temperature has weak effect on CO2 flux. Besides, large CO2 flux can be achieved with high concentration of DEA+0.2AMP solution due to the decrease of liquid phase resistance to mass transfer, but the optimal DEA concentration was recommended to be about 15% for DEA+0.2AMP solution considering the costs of amines in HFMC.

The dependence of chemical equilibrium constant on the reaction temperature and pressure and the feed molar ratio were theoretically calculated for indirect ethanol synthesis from syngas through the coupling of CO with methyl nitrite (MN) to dimethyl oxalate (DMO) and the hydrogenation of DMO to ethanol. It shows that the coupling process and the hydrogenation of DMO to ethanol are highly favorable at all temperatures and pressures, especially at low temperature. The hydrogenation of DMO to ethylene glycol (EG) and the further reaction of ethanol with H2 to high alcohol are thermodynamically favorable at low temperatures, below 630 and 450 K, respectively. Additionally, high reaction pressure is facilitated to EG and high alcohol formation. Accordingly, moderate reaction temperature (up 538 K) and low reaction pressure (below 1 MPa) are beneficial to ethanol production.

Isolation of phenols from the middle oil fraction(170-230°C) of tar produced in the multi-cogeneration system has been investigated for the purpose of recovering valuable pure phenols, such as phenol, cresols, xylenol and ethyl-phenol. Phenolic compounds were separated from the middle oil by liquid-liquid extraction using alkali and sulfuric acid. The yield of phenolic fraction from the middle oil (170-230°C) is up to 37%, which is much higher compared with those of metallurgical coke plants. Chromatography-mass spectrometry was used to analyse phenolic compounds. The result shows that the phenol content is less than 2%, and main compounds are cresol(14%), xylenol(20%) . Phenols of the middle oil fraction(230-280°C) was also analysed, which main contain methyl naphthol(20%).

Experiments were performed to investigate the release behavior of potassium and sodium in the biomass high-temperature entrained-flow gasification with the addition of acid oxide SiO2, basic oxide MgO, amphoteric oxide Al2O3. The results showed that the volatilization of alkali was found to strongly depend on temperature. High gasification temperature strengthened the alkali release. When the reactor temperature was 1200°C, the volatilization of alkali species were about 37.87% for K and 71.14% for Na. Three additives all favored the retention of potassium and sodium and the content of water-soluble potassium and sodium in the ash. Among the three additives, MgO had the best retention effect. The potassium and sodium content in the gas phase was as low as 46.6% and 67.3% compared with raw straw, respectively. In the entrained-flow gasification with short residence time, the additives retained more alkali metals by the physical and chemical adsorption. Part of the additive utilized as physical adsorbent during the gasification enhanced the ash melting point of the residue carbon.

A silica supported Cu catalyst with good performance for ethylene glycol (EG) production was prepared by the hydrolysis of tetramethoxysilane (TMOS) in one phase solution using methanol as co-solvent, followed by the precipitation of copper on SiO2 by ammonia evaporation. XRD, SEM and TEM were carried out to characterize the structural and morphology properties of the catalyst. The results showed that Cu particles were homogeneously dispersed on the support and thus lead to the high catalytic performance.