主办单位：煤炭科学研究总院有限公司、中国煤炭学会学术期刊工作委员会
Research progress on anti-poisoning of Mn-based low temperature SCR catalysts
ZHANG Cheng，LI Junchen，FANG Dingli，TAN Peng，MA Lun，FANG Qingyan，CHEN Gang
选择性催化还原技术是目前成熟可靠的脱硝技术，广泛应用于固定源氮氧化物的脱除。商用钒钛催化剂的温度窗口窄且高，为了满足非电力行业更低温度窗口的脱硝需求，低温NH3-SCR备受关注。近年来，Mn基催化剂因其良好的低温活性被认为是最具有前景的低温SCR催化剂。详细讨论不同种类锰基催化剂的性能研究以及锰基催化剂抗硫、抗水、抗碱金属/碱土金属(K、Na、Ca、Mg)和重金属（As、Zn、Pb）中毒的机理和改性方法，针对不同的抗中毒研究和改性方法进行了分析和总结，获得结论如下：① 传统非负载型Mn基催化剂最佳制备方法为共沉淀法，脱硝效率达100%；微生物处理法是新型绿色合成方法，经济环保性高，为绿色合成Mn基催化剂提供了可行路径；② 掺杂Ce、Fe、Cu、Ni、Ho、Nd、Zr、Co和Eu等元素能够有效提高Mn基催化剂的脱硝活性和抗中毒性能；可考虑将其作为“核-壳”结构的“壳”材料，提高Mn基催化剂的抗中毒性能；③ 特定孔径的分子筛是解决催化剂硫中毒的理想材料，但目前传质阻力的问题尚未解决，还需进一步优化分子筛的制备方法和工艺；④ Mn基催化剂的抗碱金属中毒集中于掺杂改性研究，改性策略分为两大类：一是增加催化剂表面耐碱的酸性位点，二是直接抑制碱金属对Mn活性组分的影响；目前上述2种改性策略的缺陷在于改性催化剂长期运行脱硝的经济性不高，需考虑从根本上杜绝催化剂与碱金属的接触；⑤ Mn基催化剂抗重金属中毒研究较少，建议开展低温段重金属迁移转化规律研究和Mn基催化剂改性的抗重金属中毒机理；⑥ 中毒后的催化剂对环境危害较大，中毒催化剂对环境危害评估和可再生利用的研究也有待进一步推进；⑦ Mn催化剂不同类型中毒之间的协同效应还有待研究，以满足Mn基催化剂的实际应用需求。
Selective catalytic reduction technology is a mature and reliable denitrification technology, which is widely used in the removal of fixed source nitrogen oxides. The temperature window of commercial vanadium-titanium catalysts is narrow and high. In order to meet the denitration requirements of lower temperature windows in the non-power industries, low-temperature NH3-SCR has received extensive attention. In recent years, manganese-based catalysts have been regarded as the most promising low-temperature SCR catalysts due to their good low-temperature activity. The performance research of different kinds of manganese-based catalysts and the mechanism of anti-sulfur, water-resistance, alkali/alkaline-earth metal (K, Na, Ca, Mg) and heavy metal poisoning (As, Zn, Pb) on manganese-based catalysts was discussed in detail. Different anti-poisoning studies and modification methods were analyzed and summarized. The conclusions are listed as follows: ① The best preparation method of traditional unsupported Mn-based catalysts is co-precipitation method, and the denitration efficiency is up to 100%. Microbial treatment method is a new green synthesis method, with high economic and environmental protection, which provides a feasible way for green synthesis of Mn-based catalysts. ② Doping elements such as Ce, Fe, Cu, Ni, Ho, Nd, Zr, Co, and Eu can effectively improve the denitration activity and anti-poisoning performance of Mn-based catalysts. They can be considered as "shell" materials of "core-shell" structure to improve the anti-poisoning performance of Mn-based catalysts. ③ Molecular sieve with specific pore size is an ideal material to solve the catalyst sulfur poisoning, but the problem of mass transfer resistance has not yet been solved, and the preparation method and process of molecular sieve need to be further optimized. ④ The anti-alkali metal poisoning of Mn-based catalysts is focused on doping modification. The modification strategies are divided into two categories: one is to increase the acid sites of alkali resistance on the surface of catalysts, the other is to directly inhibit the influence of alkali metals on the active components of Mn. At present, the defects of the above two modification strategies are that the modified catalyst is not economical in long-term operation of denitrification, so it is necessary to fundamentally eliminate the contact between the catalyst and alkali metals. ⑤ There are few studies on Mn-based catalysts′resistance to heavy metal poisoning. It is suggested to carry out research on the migration and transformation of heavy metals in low-temperature section and the mechanism of resistance to heavy metal poisoning by modification of Mn-based catalysts. ⑥ The poisoned catalyst is harmful to the environment, and the research on the environmental hazard assessment and renewable utilization of the poisoned catalyst also needs to be further promoted. ⑦ The synergistic effects between different types of poisoning of Mn catalysts remains to be studied tomeet the practical application requirements of Mn based catalysts.
NOx;Mn-based low-temperature SCR catalyst;denitrification performance;anti-poisoning performance;molecular sieve;doping modification
0 引言
1 Mn基SCR催化剂性能
1.1 非负载型Mn基催化剂
1.2 负载型Mn基催化剂
2 Mn基催化剂抗中毒机理
2.1 抗硫抗水机理
2.2 抗碱金属中毒机理
2.3 抗重金属中毒机理
3 结论及展望
主办单位：煤炭科学研究总院有限公司 中国煤炭学会学术期刊工作委员会
洁净煤技术 
2022年第10期 
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