Hydrogen sulfide removal is a long-standing economic and environmental challenge faced by the oil and gas industries. H2S 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 H2S 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.

https://pubs.acs.org/doi/pdf/10.1021/acs.chemrev.7b00768

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

Status and progress of membrane contactors in post-combustion carbon capture: A state-of-the-art review of new developments

State-of-the-art review on hollow fibre contactor technology and membrane-based extraction processes

A model developed for multicomponent gas separation using hollow-fiber contactors permits simulation of cocurrent, countercurrent, and crossflow contacting patterns with permeate purging (or sweep). The numerical approach proposed permits simulation to much higher stage cuts than previously published work and provides rapid and stable solutions for cases with many components, with widely varying permeability coefficients. This new approach also permits the rational and straightforward incorporation of effects such as permeate sweep, pressure-dependent permeability coefficients, and bore side pressure gradients. Simulation results are presented for separation of commercially significant multicomponent gas mixtures using polymer permeation properties similar to those of polysulfone. The effect of permeate purging on separation performance is explored for air separation. The influence of pressure ratio on hydrogen separation performance for a refinery stream is presented. Air is modeled as a four-component mixture of O2, N2, CO2, and H2O and the refinery stream contains five components: H2, CH4, C2H4, C2H6, and C3H8. In air separation, permeate purging with a small fraction of the residue stream provides a very effective method for improving module efficiency for drying but is not efficient for improving nitrogen purity or recovery. In multicomponent mixtures, maxima in the compositions of components of intermediate permeability may be observed as a function of distance along the hollow fiber. This result suggests the use of membrane staging to capture these components at their maximum concentration.

Modeling multicomponent gas separation using hollow‐fiber membrane contactors

Recent progresses in polymeric hollow fiber membrane preparation, characterization and applications

CO2 capture in HFMM contactor with typical amine solutions : A numerical analysis

A mathematical and numerical investigations on the gas–liquid absorption of carbon dioxide in monoethanolamine solutions in a hollow fiber membrane contactor device is described. The reactive absorption mechanism was built based on momentum and mass transport conservation laws in all three compartments involved in the process, i.e., the gas phase, the membrane barrier, and the liquid phase. The liquid absorbing solution flows in the fiber bore in which the velocity is assumed to obey a fully developed laminar flow, and the gas mixture circulates counter-currently to the liquid flow in the shell side where the velocity is characterized by the Navier-Stokes momentum balance equations. The average outlet gas and liquid concentrations, the reactive absorption flux, and the gas removal efficiencies are parametrically simulated with operational parameters such as gas flow rate, fresh inlet amine concentrations, and fiber geometrical characteristics. The shell velocity was described by other flow hydrodynamics models besides Navier-Stokes and their simulated results were favorably compared to experimental data. © 2011 American Institute of Chemical Engineers AIChE J, 2012

Carbon dioxide absorption by monoethanolamine in hollow fiber membrane contactors: A parametric investigation

The difficulties in the numerical solution of differential equations for countercurrent binary gas permeators are discussed. For a permeator with countercurrent or cocurrent flow of a binary gas mixture without axial pressure drops, a series solution technique is introduced to express each product composition as a power series in terms of a dimensionless membrane area. For countercurrent flow over a wide range of parameters, compute product compositions and fractions of the feed mixture permeating the membranes compare very well with those from a numerical solution of the governing equations for small to moderate permeate fractions in the range considered practical. For ideal separation factors of 2, 5, 10, 25, and 80, significant deviations occur at fractions larger than 0.7, 0.5, 0.33, 0.25, and 0.15, respectively, at a pressure ratio of around 0.1 and a more-permeable-component feed mole fraction around 0.2. Cocurrent flow predictions are excellent at somewhat lower permeate fractions. Preliminary countercurrent permeator design or rating problems will require solution of only one o two cubic equations.

Series solutions for a gas permeator with countercurrent and cocurrent flow

Hollow fiber membrane modules are extensively used as gas–liquid contactors for acid gas removal from waste gas streams. Hydrogen sulfide is an important indoor and outdoor contaminant, but, given its toxicity, a limited number of experimental results have been reported for this compound. Moreover, chemical absorption has been exclusively investigated. In this study, hydrogen sulfide odor control by absorption in water thanks to a hollow fiber contactor has been studied both experimentally and theoretically. The scrubbing of hydrogen sulfide from air gas mixture is investigated in two porous polypropylene (PP) hollow fiber modules of different contact area and fiber packing fraction. The gas phase is circulated in the lumen of the fiber bore and the liquid phase in the shell in a nonwetted mode, i.e. the membrane pores being filled with gas. The gas phase was run in countercurrent contact with the liquid phase at constant pressure. A laminar parabolic velocity has been employed to describe the convective diffusive mass transport equation which has been solved analytically and numerically. The calculated extents of hydrogen sulfide depletion reasonably compare with the generated experimental results for both membrane modules. Up to 85% of acid gas could be removed at gaseous flowrates of 200 cm3/min for the large module and removals as high as 89% at 10 cm3/min have been observed for the smaller one. The overall mass transfer coefficients calculated from the experimental data, agree satisfactorily with those generated by the mathematical model. The relation of the dimensionless Sherwood number to the Graetz number is in a good agreement with the Leveque semianalytical solution. © 2007 American Institute of Chemical Engineers AIChE J, 54: 122–131, 2008

Hollow fiber membrane contactor for hydrogen sulfide odor control

The problems in the numerical solution of boundary value problems encountered in hollow fiber binary gas permeatbrs having cocurrent or countercurrent permeate flow with axial pressure drop inside the fiber bore are discussed. A series solution technique is developed to express each product composition and the pressure ratio as a power series in terms of a dimensionless membrane area for shell side constant-pressure feed flow. Cocurrent or countercurrent rating or design problems require the solution of elther one algebraic equation, two coupled algebraic equations, or three coupled algebraic equations to determine the unknown quantities of interest. Calculated product and reject compositions, stage cuts, and closed-end pressure ratios compare quite well with those from numerical solutions for practically useful low to moderate cuts over a wide range of parameters. Cocurrent rating calculations requiring solution of only one algebraic equation are recommended for shortcut procedures since flow pattern effects are significant but not large.

Noureddine Boucif

Papers

CO2 capture in HFMM contactor with typical amine solutions : A numerical analysis

Carbon dioxide absorption by monoethanolamine in hollow fiber membrane contactors: A parametric investigation

Series solutions for a gas permeator with countercurrent and cocurrent flow

Hollow fiber membrane contactor for hydrogen sulfide odor control

Hollow fiber gas permeator with countercurrent or cocurrent flow: series solutions