中低煤阶高有机硫煤含硫结构演化特征

采用计算机曲线拟合方法对实验数据进行分峰处理,定量分析了9个中低煤阶高有机硫煤样的红外光谱(FT-IR)数据特征。研究表明,二硫醚与碳碳双键吸收峰面积比值(X₁)、硫醇与碳碳双键吸收峰面积比值(X₂)分别与R_max以及有机硫含量(S_o,d)呈显著的正相关性。煤质参数相近,有机硫含量及其占全硫比例受微环境的影响。同一煤样中,二硫醚、硫醇、二硫化铁三种含硫结构红外参数均依次递减。低煤阶及低-中阶烟煤阶段,以二硫醚、硫醇为代表的有机硫与含氧官能团的红外参数呈现此消彼长关系,且在第二次煤化跃变点附近,参数急剧增大。高有机硫煤样随煤阶升高,脂肪链支链化程度下降,芳构化程度加大,与一般低硫煤结构演化特征相符。 

Evolution characteristics of sulfur-bearing structures of low and medium rank coal with high organic sulfur content

By means of the computer curve-fitting method, the infrared spectra data of nine medium and low-rank high organic sulfur coals were processed and the infrared spectrum characteristics were quantitatively analyzed. The results showed that the ratio of area of mercaptan (SH), double thioether (S-S) to Carbonyl which are called sulfur-bearing structures FT-IR parameters were significant positively correlated with R_max and organic sulfur content. Organic sulfur content and total sulfur ratio is affected by micro environment. In same sample, FeS₂, SH, S-S were decreased progressively in turn. The total of -SH and S-S showed mutually complementary relation with oxygen-containing functional groups, and sharply rises at the point of second coalification jump. The IR parameters of the length and degree of branching aliphatic side chains and aromatization shows that as the rank of metamorphosed coal is high, the degree of branching aliphatic side chains decreased and the extent of aromatization increased, consistent with evolution characteristics of general low sulfur coals.