Mesoporous-molecular-sieve-supported Polymer Sorbents for Removing H2S from Hydrogen Gas Streams

Abstract

A series of sorbents with a linear polyethylenimine (PEI) supported on the mesoporous molecular sieves, including MCM-41, MCM-48 and SBA-15, have been prepared and used to remove H 2 S from a model gas containing 0.40 v% of H 2 S and 20 v% H 2 in N 2 gas. The sorption was conducted in a fixed-bed system at a temperature range of 22-75°C, a GHSV range of 337-1,011 h -1 and atmospheric pressure. The effects of the operating temperature, GHSV, the amount of PEI loading and the different molecular sieve supports were studied. A reduction in the temperature and GHSV improves the sorption performance of the supported PEI sorbents. A synergetic effect of the SBA-15 support and PEI on the H 2 S sorption performance was observed. Loading 50 wt% PEI on SBA-15 gave the best breakthrough capacity, while loading 65 wt% PEI on SBA-15 had the highest saturation capacity. The mesoporous molecular sieve with large pore size and three-dimensional channel structure favors increasing the kinetic capacity of the supported PEI sorbent. In addition, the developed sorbents can be regenerated easily at mild conditions (temperature range of 75-100°C) and have excellent regenerability and stability. The results indicate that the mesoporous-molecular-sieve-supported polymer sorbents are promising for removing H 2 S from hydrogen gas streams.

Application of polyethylenimine‐impregnated solid adsorbents for direct capture of low‐concentration CO2

“…The adsorption capacity of the adsorbent was calculated by integration of the area above the breakthrough curve and from the CO 2 concentration in the inlet gas, flow rate, adsorption time, and mass of the adsorbent. 55 Q s represents the saturation adsorption capacity calculated at the saturation time when the outlet concentration is equal to the inlet concentration, while Q b represents the breakthrough adsorption capacity calculated at the breakthrough time when the outlet concentrations are 5% of the inlet concentration. The effect of O 2 was performed using the feed gas with O 2 concentration of 20.5%.…”

“…55 In a typical preparation, the desired amounts of PEI (Mw 5 600) were dissolved in 10 g of methanol at 40 C under stirring for 30 min, and then 2 g of the support was added to the above solution and further stirred for 8 h. The slurry was then dried with continuous stirring at 40 C to remove methanol. Then, the adsorbents were dried at 80 C for 12 h under vacuum conditions.…”

Selective adsorption of thiophenic compounds from fuel over TiO2/SiO2 under UV-irradiation

“…SiO 2 (A-type) with S BET of 450 m 2 /g was provided by Sigma-Aldrich, MCM-48 with S BET of 1281 m 2 /g was synthesized in lab using hydrothermal method [19], and MCM-41 with S BET of 1200 m 2 /g was provided by Zhuoyue Chemicals, Shanghai. Two types of metal organic frameworks (MOFs), Cu-BTC (S BET of 1024 m 2 /g) and MIL-100(Fe) (S BET of 1907 m 2 /g) were prepared in lab using the hydrothermal methods [11].…”

A Novel and Cost-Effective Hydrogen Sulfide Removal Technology Using Tire Derived Rubber Particles

“…They are attractive because of the potential for high removal efficiencies, their ability to be selective for either H 2 S or both CO 2 and H 2 S removal, and are regenerable (McKinsey Zicarai, 2003). One problem associated with this process is that a portion of the amine gas is either lost or degraded during H 2 S removal and it is expensive and energy intensive to regenerate or replace the solution (Wang, Ma, Xu, Sun, & Song, 2008). Other disadvantages include complicated flow schemes, foaming problems, and how to dispose of foul regeneration air (McKinsey Zicarai, 2003).…”

“…This study, by Wang et al (2008), studied the effects on H 2 S adsorption of adding various compositions of a polymer, polyethylenimine (PEI), to a molecular sieve base. The mesoporous molecular sieves tested were amorphous silicates with uniform mesopores.…”