Instituto de Ciencia y Tecnología del Carbono, INCAR-CSIC, Francisco Pintado Fe, 26, 33011, Oviedo, Spain.
Instituto de Ciencia y Tecnología del Carbono, INCAR-CSIC, Francisco Pintado Fe, 26, 33011, Oviedo, Spain.
J Hazard Mater. 2020 Dec 5;400:123168. doi: 10.1016/j.jhazmat.2020.123168. Epub 2020 Jun 11.
The development of technologies to control mercury emissions is now a legal requirement imposed by recent international agreements. The use of regenerable sorbents is consistent with this requirement as it allows mercury to be captured from industrial gases without generating new mercury-containing toxic waste. Because regenerable sorbents based on noble metals are often questioned due to the heavy investment they entail, this study assesses the viability of their use in terms of efficiency and cost. Its primary aim is to develop new regenerable sorbents based on an activated carbon support impregnated with Ag in order to compare their cost and behavior in a CO enriched gas stream with that of similar materials containing Au. Mercury retention efficiencies of 100 % can be achieved over several adsorption-desorption cycles depending on the type of noble metal used, particle size and impurities in the gas atmosphere. The results suggest that the Hg-Ag amalgamation process differs from the Hg-Au one, in that they show different kinetics of adsorption and temperatures of desorption. The Ag and Au regenerable sorbents developed in this study would be competitive given the environmental and health benefits they offer compared to the single-use activated carbons employed until now at industrial scale.
控制汞排放的技术的发展现在是最近的国际协议所规定的法律要求。使用可再生的吸附剂符合这一要求，因为它可以从工业气体中捕获汞，而不会产生新的含汞有毒废物。由于基于贵金属的可再生吸附剂通常由于所需的巨额投资而受到质疑，因此本研究根据效率和成本评估了它们的使用可行性。其主要目的是开发基于载银活性炭的新型可再生吸附剂，以比较它们在富含 CO 的气流中的成本和行为与含有 Au 的类似材料的行为。根据所用贵金属的类型、颗粒大小和气体气氛中的杂质，可以在几个吸附-解吸循环中实现 100%的汞保留效率。结果表明，Hg-Ag 汞齐化过程与 Hg-Au 过程不同，因为它们表现出不同的吸附动力学和解吸温度。与迄今为止在工业规模上使用的一次性活性炭相比，本研究开发的 Ag 和 Au 可再生吸附剂具有环境和健康效益，因此具有竞争力。
