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Summary: In this work, we studied the effects of char structural evolution and alkali and alkaline earth metallic species (AAEMs) catalysis on the reactivity during the char gasification with CO2, H2O, and their mixture. The gasified chars with different carbon conversion levels were prepared, and their physicochemical structures were characterized via nitrogen adsorption and FT‐Raman techniques. The concentrations of AAEMs in different modes were obtained by the sequential chemical extraction method. The reactivities of the raw and gasified chars were analyzed by the thermogravimetric analysis. The gasification atmospheres had varied effects on the physicochemical structure of coal char. The gasified char obtained in the CO2 atmosphere had a lower aromatic condensation degree compared with that obtained in the H2O atmosphere, irrespective of the temperature. The impact of the atmospheres on the specific surface area of the char varied with the temperature because H2O and CO2 have different routes of development of pore structure with coal char. A large specific surface area facilitates the exposure and dispersion of more AAEMs on the surface of the channel, which is conducive to their contact with the gasification agent to play the catalytic role. Thus, the reactivity of the gasified char is well correlated with its specific surface area at different gasification temperatures. In the absence of AAEMs, the chemical structure of coal char becomes the dominant factor affecting the reactivity. [ABSTRACT FROM AUTHOR]

Cu/SBA-15 nanomaterials were synthesized by means of a simple impregnation reduction method using excess NaBH as reducing agent. The morphology and structure of synthesized materials were characterized by powder X-ray diffraction, N adsorption-desorption isothermal and transmission electron microscope. The catalytic activity of Cu/SBA-15 toward the reducing reaction of p-nitrophenol was investigated using UV-Vis spectroscope as monitor and discussed further from the viewpoints of reactive kinetics and thermodynamics. Results show that the ordered structure of mesoporous materials was still remained as Cu nanoparticles incorporated into SBA-15, and that the specific surface areas and pore diameters of materials enlarged. Cu/SBA-15 as catalytic exhibited an excellent catalytic activity and over 99.0% of p-nitrophenol was reduced into p-aminophenol. The time to complete reaction shortened as increasing of reaction temperature as well as Cu nanoparticles loaded amount. The activity energy of reduction reaction was 64.09 kJ mol and the rate constants increased as rise of the reaction temperatures from the pseudo-first-order reaction model. The thermodynamic analysis reveals that the activity parameters of reaction were as follows: enthalpy change 61.65 kJ mol, entropy change −87.68 J mol K, and Gibbs free energy change increased slightly as increasing the reaction temperature. [ABSTRACT FROM AUTHOR]

A new flame-retardant protein viscose fiber with safely wearing performance has been prepared through blending protein solution, flame retardant (hexaphenoxycyclotriphosphazene) and viscose spinning solution, in which wool protein was used and added to spinning solution on the basis of 16% flame retardant, and the properties of the fiber were investigated. The product has more compact structure inside the fiber and evenly scattered small pores on the surface. Flame-retardant protein viscose fiber can reach the flame-retardant standard both before and after 30 times wash test, and the mechanical strength of the fiber was also improved. The introduction of hexaphenoxycyclotriphosphazene lowered the primary decomposition temperature of viscose fiber, reduced its weight loss. The flame-retardancy of the fiber can be improved by the introduction of protein. In thermal processes, the major product of thermal decomposition was CO2, no hazardous and noxious gases were released. Due to the introduction of protein, moisture regain of the fiber is a little lower than that of viscose fiber, but higher than flame-retardant viscose fiber. Warmth retention property was also improved. Friction coefficient of the product is lower than that of flame-retardant viscose fiber. Bulking intensity was increased, which is better than that of viscose fiber. [ABSTRACT FROM AUTHOR]

MnTiO x catalysts with different quantities of Ti are synthesized with a hydrothermal method and employed in the catalytic oxidation of benzene. By controlling the relative content of Mn and Ti, the effect of Ti content has been investigated from physicochemical properties and activity points of view. Ti enables the formation of Lewis acid with electrophilic properties and simultaneously leads to the increase of Mn4+ and surface lattice oxygen numbers. Additionally, it is established that the addition of Ti4+ can lead to the partial substitution of Mn3+ in MnTiO x to create the Mn-O-Ti structure, improving the active oxygen transfer capacity, which is crucial for catalytic activity. After optimization, the best catalytic performance sample is MnTiO x -0.33 with the T 90 = 258 oC at GHSV = 45000 ml·g-1·h-1. It is proposed that the catalytic oxidation of benzene takes place on the surface of MnTiO x -0.33 through the MVK mechanism. [Display omitted] • The strong interaction between Mn and Ti led to the formation of Mn-O-Ti entity. • Ti incorporated into manganese oxides boosted the oxygen migration ability. • Lewis acid promoted the formation of Mn4+ from Mn2+, Mn3+ in MnTiO x catalysts. • The best catalytic performance sample is MnTiO x -0.33 with 74.6% surface Mn4+ conc. • The lattice oxygen played a critical role in the benzene oxidation process. [ABSTRACT FROM AUTHOR]

The catalytic oxidation over the selective catalytic reduction (SCR) catalysts is efficient and economical for the removal of elemental mercury (Hg0). Herein, we studied the catalytic oxidation of Hg0 over the MnCeTiO x catalysts with different Ce contents synthesized by a polyethylene glycol-assisted (PEG) co-precipitation method. By increasing the contents of Ce loaded, the oxidizability of MnCeTiO x was reduced, but the NH 3 -SCR performance and H 2 O/SO 2 resistance were improved. The MnCe(0.1)TiO x catalyst presented high NO conversion rate exceeding 80% at 160–360 °C and gas space hourly velocity (GHSV) of 80, 000 h−1 and Hg0 oxidation efficiency beyond 95% at 100–300 °C and 400, 000 h−1, respectively. The surface-active oxygen including chemisorbed surface O and unsaturated-coordinated surface lattice O acted as the active sites for Hg0 oxidation. The competitive adsorption and oxidation of SO 2 and NH 3 could suppress the adsorption of Hg0. NO and SO 2 could be oxidized into active intermediates, such as NO 3 -* and SO 4 2-* , which benefited the oxidation of Hg0. However, the NH 3 was a strong Lewis base and reducing agent, which could be oxidized to NH 2 * or NH* and then hinder the oxidation of Hg0. These results clarified the interaction among the multi-components during the oxidation of Hg0 over the SCR catalysts, which is beneficial to the development of Hg0 treatment techniques in low-temperature flue gas. [Display omitted] • MnCeTiO x catalysts with different Ce contents were synthesized. • MnCe(0.1)TiO x presented high NO conversion and Hg0 removal efficiency. • The surface-active oxygen acted as the active site for Hg0 and NO oxidation. • NO and SO 2 could benefit the oxidation of Hg0. [ABSTRACT FROM AUTHOR]