Ammonia Absorption Enhancement by Metal Halide Impregnated Hollow Mesoporous Silica Spheres

Abstract

Ammonia is one of hazardous pollutants that can endanger human life. It must be controlled with sorbent material that can target ammonia with high selectivity. Hollow mesoporous silica spheres (HMSS) are conventionally used as a carrier of catalyst. But ammonia can be absorbed selectively via impregnation of metal halide, such as MgCl2. In this work, the porous matrix HMSS is synthesized via one step preparation, and the absorption sites are adopted by impregnation method. The influence of loading content is taking into consideration on absorption performance. The structure of prepared material is analysed using FTIR, XRD, BET, TEM tools. The absorption capacity is performed in a fixed bed column and characterized by dynamic breakthrough. The results show that the composite material MgCl2/HMSS can absorb 20 mol/kg ammonia at 30 °C and 0.8 atm which is competitive than commercial sorbents. Meanwhile, 80 wt% of loading content is reported the highest ammonia capacity for the same type of sorbent. The experimental data can be reproducible for many times.

Ionic liquids and deep eutectic solvents for NH3 absorption and separation: a review

“…The porous material adsorption method uses solids [such as zeolite, graphite oxide (GO), activated charcoal (AC), silica gel (SG), alumina (Al 2 O 3 ), metal–organic frameworks (MOFs), and covalent organic frameworks (COFs)] 37–48 to purify NH 3 -containing exhaust gas. With the advantages of special solid's unique properties of high specific surface area, porosity, and specific strength, as well as low density, the adsorption process uses less energy and purifies the exhaust gas more thoroughly, but the adsorption equipment is large and only suitable for NH 3 -containing exhaust gas with low concentration.…”