硅系黏结剂对涂覆型蜂窝体催化剂性能的影响

以黏土蜂窝体为廉价载体浸涂V–W–Ti催化剂浆料，制备涂覆型蜂窝体催化剂。考察了涂覆型蜂窝体催化剂制浆过程中分散剂、黏结剂、增强剂等因素，并通过XRF, XRD, BET及SEM等手段对其表征。结果表明，黏结剂对催化剂脱硝活性和强度影响最大，黏结剂B3制备的涂覆型蜂窝体催化剂脱硝活性和强度最优，表面形成了致密的涂层，具有更高的强度。在优化参数条件下制备的涂覆型蜂窝体催化剂单孔道NO转化率达20.3%，优于商用挤出型蜂窝体催化剂(NO转化率18.1%，单孔道)，其催化剂用量显著降低。耐磨测试结果预测所制涂覆型蜂窝体催化剂在焦化厂烟气条件下稳定工作时长预期达128000 h，极具工业应用前景。

Effect of silicon-based binder on the performance of coated honeycomb catalyst

Selective reduction reaction (SCR) has become one of the most promising methods to reduce NOx emission for decades, in which catalysts play a key role to achieve good denitration (DeNOx) performance. V-based extruded honeycomb catalyst shows great advantages in the denitration process of power industry due to its high activity and excellent tolerant to SO2 and H2O, and the catalyst cost is gradually reduced with the further development of this technology. For medium/small boiler with flue gas below 300℃, however, much more expensive V has to be used to achieve high activity at low temperature, which significantly increases the catalyst cost for extruded honeycomb. Therefore, it is urgent to develop a low-cost catalyst with excellent low-temperature activity. In this work, a coated honeycomb catalyst was prepared by impregnating V–W–Ti catalyst slurry with blank clay honeycomb as an inexpensive support, and characterized by XRF, XRD, BET, SEM, etc. The results showed that the binder had a great influence on the DeNOx activity and strength of the catalyst for different kinds of dispersants, binders and reinforcing agents. Particularly, the coated honeycomb catalyst prepared by the addition of binder B3 had best DeNOx activity and strength. The prepared honeycomb catalyst with B3 binder had a dense coating on its surface to give it good strength. Moreover, the DeNOx activity increased with the increased content of catalyst coating. The coated honeycomb catalyst prepared at optimized parameters could reach 20.3% NO conversion rate for one honeycomb single-channel, which was much higher than the commercial extruded honeycomb catalyst (18.1% NO conversion rate, single-channel). Compared with extruded honeycomb, the catalyst cost used for coating honeycomb significantly reduced. In addition, the results of abrasion resistance test predicted that the prepared coated honeycomb catalyst may work stably for 128000 h in the flue gas from coking plant, which showed great industrial application prospects.