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In this study, Manganese oxide (MnO x) was supported on activated coke modified by (NH 4) 2 S 2 O 8 (ACs) to obtain novel MnO x /ACs catalysts with high NO x removal performance by excessive impregnation method. The influence of precursor and loading amount of MnO x on the catalytic efficiency were studied. The Mn 3 O 4 supported on ACs samples prepared with manganese acetate tetrahydrate as precursor and the loading amount of 8% Mn is the most effective in NO x removal among modified samples and its removal efficiency is 97% at 180 °C. And the adsorption state and reaction behaviors of NH 3 , NO and O 2 on MnO x /ACs catalysts were measured by in situ diffuse reflectance infrared Fourier transform spectroscopy (in situ DRIFTS) in different conditions in order to study the effect of MnO x and the reaction mechanism. The results suggested that Eley-Rideal and Langmuir-Hinshelwood mechanism existed simultaneously for the selective catalytic reduction of NO over the MnO x /ACs catalyst. Image 1 • High efficiency of DeNO x catalyst was formed by Mn 3 O 4 loaded on active coke. • The best precursor agent and loading amount were discussed. • The mechanism of the reaction occurred on the catalyst was studied. [ABSTRACT FROM AUTHOR]

The influence of balance gas mixture on decomposition of dimethyl sulfide was investigated experimentally by a wire-cylinder pulse corona reactor at room temperature. A new type of high voltage pulse generator with a thyratron switch and a Blumlein pulse-forming network was used in the experiments. The experiments were conducted at a fixed pulse frequency of 100pps. The DMS decomposition efficiency as well as energy yield was investigated using varying oxygen concentration (0.6–21.0%), humidity (0–1.0%) and different balance gas (air, N2, Ar). Breakdown voltage of DMS in Ar is lower than that of DMS in N2, both of which are proportional to the gas pressures. The conversion of DMS in Ar is more efficient than that in N2 and air at a fixed peak voltage. In addition, it is found that 5% oxygen is the optimum concentration in decomposition of DMS, due to higher conversion of DMS and relatively fewer yields of by products, such as O3, NO x and SO2. The highest DMS removal efficiency where the energy yield was 1.24mgkJ−1 was achieved with the gas stream containing 0.3% H2O in air. [Copyright &y& Elsevier]

By-products produced from dry flue gas desulfurization (DFGD) have been used in many engineering applications. Structural fill and/or mine reclamation applications utilize more than 74 and 22% of the annual DFGD production in Europe and the United States, respectively. In China, although there are reports showing the applications of DFGD materials in the production of bricks, precast concrete, highway construction, and agricultural applications, large-scale, high-volume uses have developed slowly. One of the major roadblocks to high-volume utilization is lack of knowledge regarding the associated utilization issues. In order to better understand the environmental response of Chinese DFGD materials, this study compared the leaching characteristics of three typical DFGD materials produced from different flue gas sources (i.e., coal-fired boiler, iron and steel sintering plant, and circulating fluidized bed (CFB) boiler). The goal of this study is to characterize the release of inorganic constituents of concern (COCs) under the leaching conditions (i.e., pH dependence, percolation column, and diffusion-controlled conditions) representing different potential application scenarios. Except for Se, the maximum concentrations of all selected COCs (Hg, B, Mo, As, Ba, Cd, Cr, Pb, Sb, Co, and Tl) under all tested leaching conditions were lower than the toxicity levels. The high release of Se observed under acidic conditions in the pH-dependent leaching tests might be adversely promoted by nitric acid induced oxidation of sparingly soluble selenite minerals to soluble selenate counterparts. Rapid initial releases of Mo, Se, B, and Tl were found during the early stages of the percolation column leaching tests. B, Mo and Se were found to be the most readily leachable COCs under the scenarios when the leaching is equilibrium-controlled. Under a diffusion-controlled leaching environment, Cr and Tl showed the highest cumulative mass release among the COCs. [ABSTRACT FROM AUTHOR]

Abstract: Amino-functionalized SBA-16 were prepared by silylating various N-(2-aminoethyl)-3-aminopropyltrimethoxysilane (AEAPS) contents on the SBA-16 supports, and their hydrophobicity, thermal and hydrothermal stabilities were investigated with water adsorption isotherms, temperature-programmed-degradation mass spectrometry (TPD-MS) and N2 adsorption–desorption. The functionalized SBA-16 samples show super hydrophobicity to the SBA-16 support, due to the coverage of silanol groups by amino-groups. The amino-groups silylated on SBA-16 are thermally stable up to 200°C both in He and in air. Decomposition in He and combustion of the amino-groups in air were observed at higher temperature (beyond 200°C), respectively. The functionalized SBA-16 samples show high hydrothermal stability and they are related to the extent of silylation. [Copyright &y& Elsevier]