A study of the reductive pyrolysis behaviour of sulphur model compounds

Organic and inorganic sulphur compounds releases from high-pyrite coal pyrolysis in H 2 , N 2 and CO 2 : Test case Chinese LZ coal

“…The shoulder around 400-550°C, refers rather to disulphides. Peak assignments in H 2 S profiles are according to previous model compound studies [28,32,35], and also based on typical aliphatic and aromatic CHfragment profiles as found in AP-TPR/MS data shown in Figs. 2 and 3 respectively.…”

“…AP-TPR/MS is a reliable method for sulphur group characterization in coal, which has already been successfully applied for sulphur functionality determination during coal pyrolysis in a reducing or inert flow [22][23][24][25][26][27][28][29][30][31][32]. The AP-TPR method is based on experimental findings that a specific sulphur functional group is maximal hydrogenated/reduced at a specific temperature range.…”

Impacts of sonication and post-desulfurization on organic sulfur species by reductive pyrolysis

“…However, if the end state is not reached, it is left in a sulfur form excluding the formation of H 2 S during an AP-TPR/MS experiment or at least to a much lesser extend [43][44][45]. Therefore, these sulfur forms will be present in an oxidized state as organic sulfoxide, sulfone or sulfonic acid compounds [46].…”

“…Except for the non-sonicated sample (only 65%), the AP-TPR/MS recoveries are relatively high (between 79% and 84%). Probably, the sonication process makes the hydrogenation of sulfur compounds also more accessible as found in the case of the microwave treatment [58], resulting in a higher AP-TPR/MS H 2 S recovery after PAA treatment. Looking in more detail to Table 7, for all desulfurized sonicated samples by PAA, the second H 2 S peak amount is always more intense than the one for the desulfurized initial sample.…”

Sulfur release and transformation behaviors of sulfur-containing model compounds during pyrolysis under oxidative atmosphere

“…In reductive atmospheres, different sulfur functional groups have been observed to decompose to some extent over a specific temperature range as follows: alkylthiols < arylthiols < disulfides < dialkyl sulfides < alkylaryl sulfides alkylaryl sulfoxides alkylaryl sulfones < pyrite < diaryl sulfides diaryl sulfoxides < diaryl sulfones < simple thiophenic structures < troilite < inorganic sulfates and complex thiophenic structures [5][6][7]. Sulfur transformation in raw coal, model compounds, or solvent extracts from coal during pyrolysis under He and H 2 atmospheres has also been studied in detail by pyrolysis with mass spectrometer (Py-MS) [4,[8][9][10]. However, sulfur release and transformation behaviors under an oxidative atmosphere are rarely reported.…”