C2O2S2 Carbonyl sulfide dimer

AbstractFor the realization of small-scale biomass-to-liquid (BTL) processes, low-cost syngas cleaning remains a major obstacle, and for this reason a simplified gas ultracleaning process is being developed. In this study, a low- to medium-temperature final gas cleaning process based on adsorption and organic solvent-free scrubbing methods was coupled to a pilot-scale staged fixed-bed gasification facility including hot filtration and catalytic reforming steps for extended duration gas cleaning tests for the generation of ultraclean syngas. The final gas cleaning process purified syngas from woody and agricultural biomass origin to a degree suitable for catalytic synthesis. The gas contained up to 3000 ppm of ammonia, 1300 ppm of benzene, 200 ppm of hydrogen sulfide, 10 ppm of carbonyl sulfide, and 5 ppm of hydrogen cyanide. Post-run characterization displayed that the accumulation of impurities on the Cu-based deoxygenation catalyst (TOS 105 h) did not occur, demonstrating that effective main impurity removal was achieved in the first two steps: acidic water scrubbing (AWC) and adsorption by activated carbons (AR). In the final test campaign, a comprehensive multipoint gas analysis confirmed that ammonia was fully removed by the scrubbing step, and benzene and H2S were fully removed by the subsequent activated carbon beds. The activated carbons achieved > 90% removal of up to 100 ppm of COS and 5 ppm of HCN in the syngas. These results provide insights into the adsorption affinity of activated carbons in a complex impurity matrix, which would be arduous to replicate in laboratory conditions.

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A solid thermal and fast synthesis of MgAl-hydrotalcite nanosheets and their applications in the catalytic elimination of carbonyl sulfide and hydrogen sulfide

New Journal of Chemistry ◽

10.1039/d0nj05809b ◽

2021 ◽

Vol 45 (7) ◽

pp. 3535-3545

Author(s):

Guanqing Zhang ◽

Xun Kan ◽

Yong Zheng ◽

Yanning Cao ◽

Shijiang Liang ◽

...

Keyword(s):

Hydrogen Sulfide ◽

Carbonyl Sulfide ◽

Superior Performance ◽

Fast Synthesis

MgAl hydrotalcites with high exposed OH− sites were designed, and showed superior performance for the catalytic elimination of COS and H2S.

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Positive trends in Southern Hemisphere carbonyl sulfide

Geophysical Research Letters ◽

10.1002/2015gl065879 ◽

2015 ◽

Vol 42 (21) ◽

pp. 9473-9480 ◽

Cited By ~ 14

Author(s):

Stefanie Kremser ◽

Nicholas B. Jones ◽

Mathias Palm ◽

Bernard Lejeune ◽

Yuting Wang ◽

...

Keyword(s):

Southern Hemisphere ◽

Carbonyl Sulfide

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Rate and Product Studies with 1-Adamantyl Chlorothioformate under Solvolytic Conditions

International Journal of Molecular Sciences ◽

10.3390/ijms22147394 ◽

2021 ◽

Vol 22 (14) ◽

pp. 7394

Author(s):

Kyoung Ho Park ◽

Mi Hye Seong ◽

Jin Burm Kyong ◽

Dennis N. Kevill

Keyword(s):

Rate Constants ◽

Isotope Effects ◽

Ion Pairs ◽

Carbonyl Sulfide ◽

Activation Parameters ◽

Chloride Ions ◽

Reaction Channels ◽

Decomposition Pathway ◽

Solvent Isotope ◽

Solvent Isotope Effects

A study was carried out on the solvolysis of 1-adamantyl chlorothioformate (1-AdSCOCl, 1) in hydroxylic solvents. The rate constants of the solvolysis of 1 were well correlated using the Grunwald–Winstein equation in all of the 20 solvents (R = 0.985). The solvolyses of 1 were analyzed as the following two competing reactions: the solvolysis ionization pathway through the intermediate (1-AdSCO)+ (carboxylium ion) stabilized by the loss of chloride ions due to nucleophilic solvation and the solvolysis–decomposition pathway through the intermediate 1-Ad+Cl− ion pairs (carbocation) with the loss of carbonyl sulfide. In addition, the rate constants (kexp) for the solvolysis of 1 were separated into k1-Ad+Cl− and k1-AdSCO+Cl− through a product study and applied to the Grunwald–Winstein equation to obtain the sensitivity (m-value) to change in solvent ionizing power. For binary hydroxylic solvents, the selectivities (S) for the formation of solvolysis products were very similar to those of the 1-adamantyl derivatives discussed previously. The kinetic solvent isotope effects (KSIEs), salt effects and activation parameters for the solvolyses of 1 were also determined. These observations are compared with those previously reported for the solvolyses of 1-adamantyl chloroformate (1-AdOCOCl, 2). The reasons for change in reaction channels are discussed in terms of the gas-phase stabilities of acylium ions calculated using Gaussian 03.

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