摘要: This paper analyzes the coal to char stages of char formation of six coals of different ranks by using Fourier transform infrared coupled with attenuated total reflectance (ATR-FTIR). The chars were obtained by coal pyrolysis carried out at temperature range of 450 ~700. The data obtained shows the pragmatic disappearance of the aliphatic hydrogen content with increasing char formation temperature. Numerical evaluation of the spectra enabled the determination of aromaticity, fa. The aromaticity was found to be between 0. 66 ~0. 79 for lignite, 0. 75 ~0. 90 for sub-bituminous, 0. 84 ~1. 00 for low volatile bituminous, 0. 83 ~ 1. 00 for high volatile bituminous, 0. 94 ~1. 00 for semi-anthracite, and 0. 97 ~1. 00 for anthracite respectively. With increasing rank of coal samples, spectra exhibit rising aromaticity and enhanced condensation of aromatic rings, whereas the aliphatic chain lengths decrease.
摘要: In this research, 1-butyl-pyridinium tetrafluoroborate ([C4Py][BF4]-) was prepared by ion exchange method and was characterized by 1H-NMR, 13C-NMR, and FT-IR techniques. The synthesized ionic liquid was used for removal of dibenzothiophene as a typical organosulfur pollutant from organic medium. The effect of different parameters on the extraction efficiency was studied and optimized. At the optimized conditions, 97.68% of dibenzothiophene was extracted from 1 000 mg/L n-hexane solution. The extraction efficiency obtained in this work was higher than the previous reported values. The desulfurization reaction was kinetically followed the second order mechanism. The ionic liquid was reusable and after four regeneration cycles 97% of its original extraction efficiency was retained.
