Removal of Hydrogen Sulfide From Various Industrial Gases: A Review of The Most Promising Adsorbing Materials

Abstract

The separation of hydrogen sulfide (H2S) from gas streams has significant economic and environmental repercussions for the oil and gas industries. The present work reviews H2S separation via nonreactive and reactive adsorption from various industrial gases, focusing on the most commonly used materials i.e., natural or synthetic zeolites, activated carbons, and metal oxides. In respect to cation-exchanged zeolites, attention should also be paid to parameters such as structural and performance regenerability, low adsorption temperatures, and thermal conductivities, in order to create more efficient materials in terms of H2S adsorption. Although in the literature it is reported that activated carbons can generally achieve higher adsorption capacities than zeolites and metal oxides, they exhibit poor regeneration potential. Future work should mainly focus on finding the optimum temperature, solvent concentration, and regeneration time in order to increase regeneration efficiency. Metal oxides have also been extensively used as adsorbents for hydrogen sulfide capture. Among these materials, ZnO and Cu–Zn–O have been studied the most, as they seem to offer improved H2S adsorption capacities. However, there is a clear lack of understanding in relation to the basic sulfidation mechanisms. The elucidation of these reaction mechanisms will be a toilsome but necessary undertaking in order to design materials with high regenerative capacity and structural reversibility.

Bimetallic Ni-Based Catalysts for CO2 Methanation: A Review

“…The optimal Ni to promoter molar ratio was five. Such catalysts were also proven to be resistant upon sulphur poisoning, since H 2 S was preferentially adsorbed at the metal promoter phases [ 56 ], thus preserving the Ni active sites [ 57 ].…”

CuWO4 with CuO and Cu(OH)2 Native Surface Layers for H2S Detection under in-Field Conditions

“…The dependence of the response and recovery transients with respect to the operating temperature are due to several reasons. It is known that the nature of the oxygen species adsorbed on the surface are strongly dependent on the operating temperature [ 38 ]. Secondly, the oxidation reaction of the H 2 S is an activated process with an increasing rate as the operating temperature increases.…”

Hydrogen Sulfide (H2S) Removal via MOFs

“…MOFs can exhibit significant advantages in gas selectivity and separation due to their large surface area (typically ranging from 1000 to 10,000 m 2 /g), diverse structure, molecular dimensions, and tunable functionality [29]. For instance, the chemistry of their pores can be improved by different methods, such as metal ion exchange.…”

“…In physisorption, the adsorptive interaction is largely ascribed to noncovalent interaction (i.e., electrostatic interactions and Van Der Waals), which is highly associated with the distance between adsorbents and adsorbates. Moreover, the reversibility of an adsorption process is pertinent to the occurrence of noncovalent bonding between the functionalized linkers and H 2 S molecules [29].…”