Absorption and Removal Efficiency of Low-Partial-Pressure H₂S in a Tetramethylammonium Glycinate Activated N-Methyldiethanolamine Aqueous Solution

Abstract

The absorption performance including absorption capacity and loading values of low-partial-pressure H2S in tetramethylammonium glycinate ([N1111]­[Gly]) promoted N-methyldiethanolamine (MDEA) aqueous solution was measured. The apparent absorption rate was calculated from the time-dependent absorption capacity. The effects of absorbent composition, temperature, and H2S partial pressure on absorption capacity and apparent absorption rate were demonstrated. The H2S removal efficiency was verified in a tray tower using the [N1111]­[Gly]–MDEA aqueous solution as an absorbent, and the results show that the removal efficiency can reach 100%, which met the requirement of the first degree of Chinese cleaner production standard (coking industry, HJ/T 126-2003, I, H2S ≤ 0.2 g/m3). Compared with the traditional amine-based absorbents like MDEA–monoethanolamine aqueous solution, the [N1111]­[Gly]-promoted MDEA aqueous solution has a higher absorption capacity and a higher absorption rate for H2S. Moreover, when the mass fraction of MDEA reaches up to 50%, the removal efficiency in the tray tower can still reach 100%. The decrease of the water content in the absorbent can greatly reduce the energy cost of the regeneration of rich solution and the cooling of poor solution. Therefore, the new absorbent proposed in this work has good commercial application potential in the field of desulfurization of the coke oven gas.

Simultaneous Removal of CO2 and H2S from Biogas by Blending Amine Absorbents: A Performance Comparison Study

“…However, based on the research results, PZ is a new carcinogen. Formation of alternative materials is needed . New blending absorbents have to be developed to remove acid gases as a substitute for MDEA/PZ.…”

“…In addition, the absorption rate and the desorption amount of H 2 S at atmospheric pressure using the monoethanolamine/MDEA absorbent showed a 95% absorption performance . AAIL/MDEA absorbents were used to test the absorption performance of H 2 S to show superior commercial sorbents for desulfurization . Based on the previous studies, the study of blending amine absorbents for simultaneous absorption and regeneration of CO 2 and H 2 S is required.…”

“…In selecting additive materials, PZ, 2-amino-2-methyl-1-propanol (AMP), diethylenetriamine (DETA), tetraethylenepentamine (TEPA), bis­(3-aminopropyl)­amine (APA), and so forth have been proved as additives for MDEA because of their excellent kinetic rate constants for CO 2 absorption. ,,, Simultaneous absorption and desorption experiments using MDEA-based additives were carried out, and CO 2 and H 2 S absorption was studied for sterically hindered amine AMP. − In general, carbamate formation is faster than bicarbonate formation, so primary and secondary amines exhibit faster CO 2 absorption than tertiary amines. , When additives were added to MDEA, the main absorbent, H 2 S absorption increased compared to MDEA only at atmospheric pressure …”

Hydrogen Sulfide Adsorption by Iron Oxides and Their Polymer Composites: A Case-Study Application to Biogas Purification

“…Watanabe [ 8 ] critically analyzed the aforementioned technologies for natural gas desulphurization, usually relying upon liquid absorption, slurry reactors and fixed-bed columns. Alkylamine absorbents for sour gases [ 9 ] are typically adopted in large facilities [ 10 ] and they are economically demanding for high operating costs [ 11 ], together with drawbacks related to limitations in the selectivity and progressive degradation of the liquid sorbent. Slurry reactors [ 12 ] allow a good solid-fluid material exchange at relatively low operating temperatures and may represent, even in terms of sorbent recovery, a valid alternative to fixed-bed reactors.…”

Surface Thermodynamics, Viscosity, Activation Energy of N-Methyldiethanolamine Aqueous Solutions Promoted by Tetramethylammonium Arginate

“…In our previous studies, we used MDEA aqueous solutions promoted by two ILs, namely tetramethylammonium glycinate ([N 1111 ][Gly]) and tetramethylammonium arginate ([N 1111 ][Arg]), to explore the performances of such mixed solutions for absorbing H 2 S. The results showed that the two AAILs were superior to MEA in promoting the absorption of H 2 S by MDEA solution. Moreover, of these two promoters, the MDEA aqueous solutions promoted by [N 1111 ][Arg] exhibited the highest absorption capacity and absorption rate for low-concentration H 2 S. Therefore, [N 1111 ][Arg]-promoted MDEA aqueous solutions show commercial potential [ 12 , 25 ].…”