Based on the synthesis of DDS in fluidization bed,a new method that can remarkably enhance reactivity and selectivity of the copper-silicon contact mass is investigated experimentally. DDS is produced from silicon and...Based on the synthesis of DDS in fluidization bed,a new method that can remarkably enhance reactivity and selectivity of the copper-silicon contact mass is investigated experimentally. DDS is produced from silicon and methyl chloride at about 300?℃in the direct synthesis process. The catalyst used in this reaction system is active cuprous chloride powder,which usually forms conglomeration of powder. The conglomerate of catalyst is known to be harmful to the synthesis reaction. Treated by ultrasonic energy,conglomeration of active cuprous chloride catalyst is destroyed,so as to achieve better proportioned dispersion of silicon and catalyst powder. By this means, CuCl catalyst is distributed evenly on the surface of silicon powder, thereby reaction activity and selectivity are increased in the synthesis process of DDS. Using ultrasonic dispersion achieves the same reaction activity with smaller catalyst dosage than the normal dispersion method.展开更多
Fluidization characteristics of silicon particle system are studied by the pressure fluctuation method.The existence of fine particles in the system can improve fluidization. Silicon particles with a wide size distrib...Fluidization characteristics of silicon particle system are studied by the pressure fluctuation method.The existence of fine particles in the system can improve fluidization. Silicon particles with a wide size distribution,preferably with some fines, behave as Group A particles according to Geldart classification, although the system belongs to Group B actually. The system is also approved to be suitable for organochlorosilane monomer production using a fluidized bed reactor. Experimental data obtained in this work are important for the design and operation of commercial fluidized bed reactors for the production of organochlorosilane monomers.展开更多
The effect of copper concentration on the performance of the catalytic reaction between silicon and methyl chloride was investigated using online gas chromatogram. The catalyst concentration greatly influences various...The effect of copper concentration on the performance of the catalytic reaction between silicon and methyl chloride was investigated using online gas chromatogram. The catalyst concentration greatly influences various aspects of the direct organosilane synthesis process, including the reaction rate, the selec- tivity, and the silicon conversion. The reaction activity and the silicon conversion increase as the catalyst concentration increases. However, the reaction selectivity decreases for the catalyst concentrations more .than 9 wt.%. The cross-sections of deactivated contact mass particles were observed by optical microscopy and analyzed by scanning electron microscope combined with energy dispersive X-ray detector （SEM-EDX） The observations showed that a textured substance formed on the original flat surface of the silicon particles after deactivation with copper only in a shallow surface layer of the contact mass. This indicates that the copper diffusion is the rate limiting step which causes the reaction deactivation.展开更多
文摘Based on the synthesis of DDS in fluidization bed,a new method that can remarkably enhance reactivity and selectivity of the copper-silicon contact mass is investigated experimentally. DDS is produced from silicon and methyl chloride at about 300?℃in the direct synthesis process. The catalyst used in this reaction system is active cuprous chloride powder,which usually forms conglomeration of powder. The conglomerate of catalyst is known to be harmful to the synthesis reaction. Treated by ultrasonic energy,conglomeration of active cuprous chloride catalyst is destroyed,so as to achieve better proportioned dispersion of silicon and catalyst powder. By this means, CuCl catalyst is distributed evenly on the surface of silicon powder, thereby reaction activity and selectivity are increased in the synthesis process of DDS. Using ultrasonic dispersion achieves the same reaction activity with smaller catalyst dosage than the normal dispersion method.
文摘Fluidization characteristics of silicon particle system are studied by the pressure fluctuation method.The existence of fine particles in the system can improve fluidization. Silicon particles with a wide size distribution,preferably with some fines, behave as Group A particles according to Geldart classification, although the system belongs to Group B actually. The system is also approved to be suitable for organochlorosilane monomer production using a fluidized bed reactor. Experimental data obtained in this work are important for the design and operation of commercial fluidized bed reactors for the production of organochlorosilane monomers.
文摘The effect of copper concentration on the performance of the catalytic reaction between silicon and methyl chloride was investigated using online gas chromatogram. The catalyst concentration greatly influences various aspects of the direct organosilane synthesis process, including the reaction rate, the selec- tivity, and the silicon conversion. The reaction activity and the silicon conversion increase as the catalyst concentration increases. However, the reaction selectivity decreases for the catalyst concentrations more .than 9 wt.%. The cross-sections of deactivated contact mass particles were observed by optical microscopy and analyzed by scanning electron microscope combined with energy dispersive X-ray detector （SEM-EDX） The observations showed that a textured substance formed on the original flat surface of the silicon particles after deactivation with copper only in a shallow surface layer of the contact mass. This indicates that the copper diffusion is the rate limiting step which causes the reaction deactivation.
