Enhanced removal of hydrogen sulfide from a gas stream by 3-aminopropyltriethoxysilane-surface-functionalized activated carbon

Abstract

A commercial activated carbon was functionally modified by silylation with 3-aminopropyltriethoxysilane (APTES). The silylation led to the fixation of weakly basic functional groups, -NH 2 , on the surface as indicated by pH titration, Boehm titration, N 2 − BET analysis and X-ray photoelectron spectroscopic (XPS) analysis. Despite reducing the specific BET area and the pore volume, silylation improved the H 2 S removal capacity so that APTES modified activated carbon (APTES-AC) was 3.55 times more effective than the original activated carbon. XPS results indicate that H 2 S removal may be associated with the amino (-NH 2 ) group and the presence of sulfur in the four oxidation states S 2− , S 0 , S 4+ and S 6+ . The effects of moisture, oxygen content and temperature on the performance of APTES-AC for H 2 S removal were investigated. The presence of moisture in the gas stream was found to have an adverse effect on the H 2 S removal, whilst the presence of oxygen favored the removal of H 2 S by APTES-AC. The higher removal capacity of APTES-AC relative to the original activated carbon indicates that APTES-AC is a potential candidate for the removal of H 2 S from gas streams. The H 2 S removal efficiency of APTES-AC was proved be superior to that of Na 2 CO 3 -impregnated AC by the pilot-scale test of purification H 2 S containing industrial waste gas, yellow phosphorus off-gas.

Adsorption/desorption of low concentration of carbonyl sulfide by impregnated activated carbon under micro-oxygen conditions

“…The O 1s spectra are fitted with three peaks and their binding energies, chemical shifts, and relative contents are also reported in Table 4. The O 1s spectra before adsorption reveal the presence of three peaks: peak I (binding energy = 530.7-531.0 eV) corresponds to C O groups (ketone, lactone, and carbonyl), peak II (binding energy = 532.2-533.0 eV) to carbonyl oxygen atoms in esters, amides, carboxylic anhydrides, and oxygen atoms in hydroxyls or ethers, and peak III (binding energy = 533.2-533.8 eV) to C O type oxygen atoms in C OH and COOR groups [29,30,32]. Only one peak corresponds to carbonyl oxygen atoms is observed after the adsorption.…”

“…These distinct energies allow the identification of different species. The C 1s spectra are well fitted with three peaks assigned to carbon atoms bound to carbon and/or hydrogen atoms (binding energy = 284.76-284.80 eV), to carbon atoms bound to oxygen atoms by one and two bonds (binding energy = 286.16-286.36 and 287.57-287.67 eV, respectively) [29,30]. The data in Table 4 indicate that the adsorption of Cu-Co-KW for COS has little influence on the electronic state of carbon atoms and C 1s.…”

Sorptive Removal of Hydrogen Sulfide from Gas Streams by an Mg‐Al Layered Double Hydroxide

“…SO 2 , a corrosive and toxic gas, is the major combustion product of H 2 S. H 2 S is emitted from widespread sources, such as food processing, coal gasifiers, pharmaceutical plants, animal processing plants, semiconductor plants, and so on. [1][2][3] H 2 S not only erodes equipment and causes poisoning of the catalyst in the course of processing industrial waste gases, but is also harmful to human health. [4] Thus, it is imperative for pollution and safety control to remove H 2 S. To date, several treatment technologies have been reported, [5] among which washing and sorption methods have been most frequently used.…”

PSS sorbents for removing trace hydrogen sulfide in methane

“…H 2 S could cause the catalyst of chemical process poisoned, the engine of natural gas vehicles corroded, and environment pollution when natural gas or coalbed methane is burned. Therefore, the purification of natural gas becomes more and more important [1][2][3][4][5][6].…”