Jiangxi Academy of Environmental Sciences, Nanchang, People's Republic of China.
School of Land Resources and Environment, Key Laboratory of Agricultural Resource and Ecology in the Poyang Lake Basin of Jiangxi Province, Jiangxi Agricultural University, Nanchang, People's Republic of China.
J Air Waste Manag Assoc. 2021 Jun;71(6):689-700. doi: 10.1080/10962247.2021.1873205. Epub 2021 Feb 5.
To eliminate nitrogen oxides (NO), composite carrier-supported catalysts (Mn-Ce/MWCNT-W) and traditional catalysts (Mn-Ce/MWCNT and W-Mn-Ce/MWCNT) were prepared using an ultrasonic impregnation method that preformed low-temperature ammonia-selective catalytic reduction (SCR) removal of NO. The promotion effects of MWCNT-W composite carriers for low temperature SCR activities and SO tolerance of the catalysts were systematically investigated. Compared to traditional catalyst, Mn-Ce/MWCNT-W catalyst, with a 30% WO/MWCNT mass ratio, demonstrated improved SCR activity and high N-selectivity from 100°C to 200°C. A series of characterizations were carried out and it was found that there were more redox sites and the stronger the NH adsorption capacity over the composite carrier-supported catalysts than traditional catalysts. Also, with this composite carrier-supported catalyst, the improvement of SCR reaction was considered to be from the abundance of high valence state Mn and well dispersed active components. Notably, compared to traditional catalyst, the composite carrier-supported catalyst exhibited the stronger sulfur resistance. Thus, using MWCNT-W composite carriers to prepare Mn-Ce/MWCNT-W catalysts resulted in excellent NO conversion and SO resistance at low temperatures.: LT NH-SCR of NO is an effective way to remove NO from stationary sources. The physicochemical properties of the support not only affect a catalyst's LT SCR activity but also affect the catalyst's anti-poisoning performance. The modified carriers could promote active component dispersion, which is conducive to SCR reaction. However, for LT SCR reactions, few reports have addressed the design and preparation of composite carrier-supported catalysts. The goal of this study was to design and synthesize Mn-Ce/MWCNT-W catalysts and to observe the influence of composite support in Mn-based catalysts on LT SCR activity and sulfur resistance.
为了消除氮氧化物 (NO)，采用超声浸渍法制备了复合载体负载型催化剂 (Mn-Ce/MWCNT-W) 和传统催化剂 (Mn-Ce/MWCNT 和 W-Mn-Ce/MWCNT)，用于低温氨选择性催化还原 (SCR) 去除 NO。系统研究了 MWCNT-W 复合载体对催化剂低温 SCR 活性和 SO2 耐受性的促进作用。与传统催化剂相比，具有 30% WO/MWCNT 质量比的 Mn-Ce/MWCNT-W 催化剂在 100°C 至 200°C 范围内表现出更高的 SCR 活性和高 N 选择性。进行了一系列表征，发现复合载体负载型催化剂比传统催化剂具有更多的氧化还原位点和更强的 NH 吸附能力。此外，在这种复合载体负载型催化剂中，SCR 反应的改善被认为是由于高价态 Mn 的丰富和活性成分的良好分散。值得注意的是，与传统催化剂相比，复合载体负载型催化剂表现出更强的抗硫性。因此，使用 MWCNT-W 复合载体制备 Mn-Ce/MWCNT-W 催化剂可在低温下实现优异的 NO 转化率和抗 SO2 性能：低温 NH-SCR 是去除固定源 NO 的有效方法。载体的物理化学性质不仅影响催化剂的低温 SCR 活性，而且影响催化剂的抗中毒性能。改性载体可以促进活性成分的分散，有利于 SCR 反应。然而，对于低温 SCR 反应，很少有报道涉及复合载体负载型催化剂的设计和制备。本研究的目的是设计和合成 Mn-Ce/MWCNT-W 催化剂，并观察复合载体在 Mn 基催化剂中对低温 SCR 活性和抗硫性的影响。
