Through the analysis of trial use of heavy oil emulsifying technology in C-glass furnaces,the feasibility of this technology in oil-fired fiberglass furnaces is expounded,in the hope of discussing with the experts in the industry to further tap the potential of this technology so as to expand its use to reduce the operation cost of involved factories and contribute to the energy saving action in the country as well.
<p><a></a><a>The development of Earth-abundant reusable and no-toxic heterogeneous catalyst applied in the pharmaceutically, bio-active relevant compounds synthesis as well as other organic syntheses still remains as the most important goal of the general chemical research. N-methylated compounds, as one of the most essential bioactive compounds,</a> have been widely used in the fine and bulk industries for the production of high-value chemicals including pharmaceuticals, agrochemicals, and dyes. As their reports, activated toxic methyl iodide and dimethyl sulfoxide were usually employed in the traditional N-methylation, which easily suffer from narrow scopes of amines, generation of by-products, and a large amount of waste. <a>Very recently, </a>transition metal-catalyzed methylation of amines has become an efficient, practical, and cost-effective method for the one-pot selective synthesis of N-methylamines with C<sub>1</sub> sources. Herein, we first developed a simple and <a>environmentally friendly</a> method for the preparation of efficient, reusable, and low-cost graphene spheres encapsulated Ni/NiO nanoalloy catalysts (Ni/NiO@C) for highly selective synthesis of the N-methylated compounds by using various functional amines and aldehydes under easily handle-able and industrially <a></a><a>applicable </a>conditions.<b> </b>A large number of primary, secondary amines (more than 70 examples) could be converted smoothly to the corresponding N, N-dimethylamines with the participation of different functional aldehydes. The gram-scale synthesis was also demonstrated in an excellent yield; not only that, the catalyst was further proved that it could be easily recycled by its intrinsic magnetism and reused up to ten times without losing activity and selectivity. Both of them are the great advantages in contrast to other catalysts reported previously. And also, for the first time, we have developed the highly efficient, cost-effective tandem synthesis of N, N-dimethylamines products in a one-pot process by means of aldehydes and NH<sub>3</sub>. As far as we know, this is the first example of the synthesis of tertiary amines with the combined reaction process of reductive amination of aldehydes and N-methylation of primary amines only with the single one earth-abundant metal catalyst. Overall, the advantages of this newly developed method including operational simplicity, high stability, easily recyclable, cost-effective of the catalyst, and good functional group compatibility for the synthesis of N-methylation products, as well as the highly efficient and industrial applicable tandem synthesis process.</p>
The rapid development of large-scale livestock husbandry has caused serious air pollution problems (e.g., The Tuzuoqi demonstration farm belonging to the Yili Group. The farm is located in the suburb of Hohhot City in northern China). In this study, the gases in typical areas of a large-scale dairy farm were sampled and measured for volatile organic compounds (VOCs), hydrogen sulfide, and ammonia concentrations. Fifty-two species of VOCs were identified. The VOCs emitted from the cowshed mainly consisted of halogenated hydrocarbons (16,960 µg/m3), ketones (15,700 µg/m3), esters (9889 µg/m3), and sulfur compounds (3677 µg/m3). The VOCs from the oxidation pond were mainly composed of halogenated hydrocarbons (21,940 µg/m3) and ketones (3589 µg/m3). The VOCs from the solid-liquid separation tank comprised halogenated hydrocarbons (32,010 µg/m3), ketones (7169 µg/m3), and sulfur compounds (1003 µg/m3). The highest concentrations of ammonia and hydrogen sulfide were obtained from the milking parlor and solid-liquid separation tank, respectively. The ammonia concentration declined gradually due to the superposition of ammonia emitted from the cowshed and milking parlor. Analysis results of the influences of distance and meteorological factors on the dispersion of ammonia and hydrogen sulfide suggested that the dilution factors decreased with increasing distance from the emission source. Within distance ranges of 0-10 and 10-25 m, the concentration dilution factors were positively correlated with wind speed and temperature but negatively correlated with humidity and atmospheric pressure. The results of our work can provide a theoretical basis for the prevention and control of odorous gases in large-scale livestock farms. Implications: Gases in typical areas of a large-scale dairy farm were sampled, and a total of 52 species of VOCs were identified. The highest concentrations of ketones, sulfur compounds, and esters were obtained at the cowshed (15,700, 3677, and 9889 µg/m3, respectively). Within the distance ranges of 0-10 and 10-25 m, the concentration dilution factors were positively correlated with wind speed and temperature.
The devolatilization of solid fuels will cause remarkable changes to the pore structures of the resulting char particles, which has a significant influence on successive reactions, such as the combustion of the char particles and the formation of ash. In the present work, the pore structures of shale chars prepared under different retorting conditions were measured by employing a N2 adsorption−desorption method. On the basis of the measured results and thermal degradation mechanisms of the kerogen within oil shale, the effects of four retorting parameters on the pore structures of shale char were discussed. An elevating retorting temperature will notably increase the pore volume and specific surface area in shale char. However, at the higher retorting temperatures, the cracking and carbonization of residual organic matter within shale char become more intensive. Subsequently, the pores are easily blocked (especially small pores), and the specific surface area of the char particles decreases slightly. In terms of the residence time of retorting at a low temperature of 430 °C, sufficient residence time is required for forming more extensive porosity within shale char particles. The particle size and low heating rate were found to have little effect on the surface area and pore volume of shale char.
Highly selective catalytic hydrogenation of alkynes to alkenes is a highly important reaction owing to its industrial and commercial application. Specifically, semihydrogenation of terminal alkynes has been more challenging than internal alkenes even using Lindlar catalysts. Also, the high reduction degree state metal-supported catalysts like Pd0/C, Pt0/C, and Ru0/C have been well-known to be used widely in hydrogenation due to their super activity. However, charcoal can absorb a large amount of water; Pd/C with 50% water is convenient on a large-scale synthesis. Charcoal generally bears oxygen groups on its surface, which are responsible for low selectivity and undesired products. Even typically, only 10-60% of the Pd metal atoms are exposed, they still suffer from poor stability in acids owing to leaching. Herein, we intend to design active and stable metal catalysts with features as the following to avoid leaching: having strong interaction with the support and coordinatively unsaturated metal sites or low valence state metals physically isolated from the acid environment. Herein, a highly efficient semihydrogenation of terminal alkynes to produce alkenes has been realized using a heterogeneous Pd(II)/POP-GIEC catalyst, imine-linked, crystalline, and porous organic polymer supporter modified by coordination of Pd(OAc)2 to its walls under mild conditions. Surprisingly, for the first time, modified POP-supported low reduction degree PdII catalysts were synthesized efficiently, and they were successfully used in semihydrogenation of terminal alkynes. The substrate scope was studied and included both unfunctionalized as well as functionalized substituents on the para, ortho, and meta position of aromatic alkynes. The substrate having a substituent with the functionality of fluoro protected at the meta position was semihydrogenated with a high alkyne conversion of 100% and olefin selectivity (up to 99%).
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