Dynamic Desulfurization Process over Porous Zn–Cu-Based Materials in a Packed Column: Adsorption Kinetics and Breakthrough Modeling

Abstract

Hydrogen sulfide, a toxic gas, is usually present in industrial coal gas and harms the environment and human health. Therefore, developing selective desulfurization materials and getting insights into their reaction mechanism have attracted great attention. In this work, we systematically investigated the kinetic process of H 2 S adsorption over porous Zn−Cu-based adsorbents in a packed column. The effects of gas hourly space velocity (GHSV), feeding concentration, and operation temperature were also investigated, respectively. The results indicated that better desulfurization performance was obtained with decreasing GHSV and increasing reaction temperature, whereas the effect of H 2 S concentration can be negligible. Among the kinetics processes, adsorption kinetics can be accurately interpreted by the RPM involving two stages, with the apparent activation energy of the product layer diffusion of 19.09 kJ/mol. According to the Bohart−Adams model, breakthrough curves can be exactly predicted with <2% error. This investigation is expected to provide fundamental support for H 2 S cleaning treatment in metallurgical and chemical industries.

The effect of the active carbonyl groups and residual acid on the ammonia adsorption over the acid-modified activated carbon

“…Ammonia (NH 3 ) is a highly toxic and extremely corrosive pollutant, which may bring undesired odors, lead to severe burning of respiratory systems, and contribute to fine particulate matter (PM2.5) concentration in the atmospheric environment (Stokstad 2014;Han et al, 2021;Jiang et al, 2022). Many different sources can release NH 3 , including home/public toilets, farm manure, liquid NH 3 refrigerants, construction waste antifreeze, expansion agents, industrial desulfurization/denitrification units (Dai et al, 2019;Zhong et al, 2019;Liang et al, 2020). In recent years, ammonia pollution has caused increasing concerns about the environment and human health around the world, and rigid standards (e.g., National Emission Ceilings Directive 2016/2284/EU, GB/T 34340-2017) have been put out to restrict the ammonia emission (Wang et al, 2017a;Giannakis et al, 2019).…”