Hydrogen Sulfide Capture: From Absorption in Polar Liquids to Oxide, Zeolite, and Metal–Organic Framework Adsorbents and Membranes

Abstract

Hydrogen sulfide removal is a long-standing economic and environmental challenge faced by the oil and gas industries. HS separation processes using reactive and non-reactive absorption and adsorption, membranes, and cryogenic distillation are reviewed. A detailed discussion is presented on new developments in adsorbents, such as ionic liquids, metal oxides, metals, metal-organic frameworks, zeolites, carbon-based materials, and composite materials; and membrane technologies for HS removal. This Review attempts to exhaustively compile the existing literature on sour gas sweetening and to identify promising areas for future developments in the field.

Highly selective absorption separation of H2S and CO2 from CH4 by novel azole‐based protic ionic liquids

“…Although these PILs have significant larger H 2 S/CO 2 ideal selectivity than normal ILs, they were proved to be as physical absorbents and would be fully utilized under high H 2 S partial pressure. As mentioned in previous literatures, good absorbents have not only high absorption capacity but also distinguished H 2 S and CO 2 separating ability 16 . The challenge of low H 2 S/CO 2 selectivity urged us to design dual Lewis base ILs incorporated with both tertiary amine and carboxyl as functionalized sites toward highly selective separation of H 2 S and CO 2 17 .…”

Hierarchical Titanium Dioxide Nanowire/Metal–Organic Framework/Carbon Nanofiber Membranes for Highly Efficient Photocatalytic Degradation of Hydrogen Sulfide

“…Nowadays, photocatalytic technology is considered one of the most economical and effective ways to decrease various environmental pollutants, because of its advantages such as nontoxicity, high degradation efficiency, and strong oxidation and reduction capability . Meanwhile, numerous semiconductor metal oxide photocatalysts have been developed to adsorb or catalytically degrade hazardous H 2 S . Among these photocatalysts, titanium dioxide (TiO 2 ) has been widely recognized as a promising material because of its suitable band gap, low cost, high photosensitivity, and nontoxic nature .…”

“…[1,2] Nowadays, photocatalytic technology is considered one of the most economicala nd effective ways to decrease various environmental pollutants, because of its advantages such as nontoxicity,h igh degradation efficiency, and strong oxidation and reduction capability. [3] Meanwhile, numerouss emiconductor metal oxide photocatalysts have been developed to adsorb or catalytically degrade hazardousH 2 S. [4,5] Among these photocatalysts,t itaniumd ioxide (TiO 2 )h as been widely recognized as ap romising material because of its suitable band gap, low cost, high photosensitivity,a nd nontoxic nature. [6] For instance, Ts uyoshi et al summarized lots of studies with theoretical strategiesf or effective design of the systemsb ased on fundamentals of TiO 2 photocatalysts and their broad environmental purification applica-tions,i ncluding gaseousc ontaminants, aqueous contaminants, and sterilization.…”

Understanding the Reactive Adsorption of H2S and CO2 in Sodium‐Exchanged Zeolites

“…Recently, ionic liquids and deep eutectic solvents have been suggested as more sustainable physical solvents for H 2 S/CO 2 capture; however, the costs of such absorption‐based separations still remain relatively high. Adsorption using molecular sieves, such as cation‐exchanged zeolites, has been a promising alternative for gas sweetening in general and selective H 2 S (over CO 2 ) removal in particular …”

“…Adsorption using molecular sieves, such as cation-exchanged zeolites, has been ap romising alternative for gas sweeteningi ng eneral and selective H 2 S (over CO 2 )r emoval in particular. [6,7,8,9] H 2 Sa nd CO 2 can react chemically to form carbonyl sulfide (COS) and H 2 O[ Eq. (1)]:…”