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1.
Studies of elemental distributions within discrete coal macerals: Use of secondary ion mass spectrometry and X-ray photoelectron spectroscopy 总被引:3,自引:0,他引:3
N.Stewart Mclntyre Ronald R. Martin William J. Chauvin C.Gordon Winder James R. Brown J.Anthony MacPhee 《Fuel》1985,64(12):1705-1712
Secondary ion mass spectrometry has been used to measure qualitatively the distributions of many trace and minor elements within some well-characterized coal macerals: vitrinite, fusinite and exinite. Complementary information was obtained by using X-ray photoelectron spectroscopy. Within the vitrinite specimens studied, a widely-dispersed largely inorganic aluminosilicate phase was identified, which contained a number of other trace elements. By contrast, within the organic-rich phase of this macerai, titanium was detected in a very even distribution; this suggests that some titanium may be bonded in an organic complex. The fusinite was shown to contain elevated concentrations of calcium, magnesium and fluorine, dispersed over a large portion of the maceral. The high fluorine content could be identified as an organo-fluoro compound using XPS. Exinite was found to contain lower concentrations of most elements, compared to other macerals. The organic composition of this maceral was significantly different from that of surrounding macerals; this could be seen from the enhanced emission of the C2H2-secondary ion and images of this ion thus clearly outlined the position of such macerals. 相似文献
2.
A suite of density-differentiated macerals from several coals was analysed by Fourier transform infrared spectroscopy to obtain information on the nature and magnitude of the variations exhibited by the various maceral fractions. The most characteristic change between maceral groups was the variation in aliphatic hydrogen content, with exinite ? vitrinite ? inertinite. Since the separation technique (density gradient centrifugation) generally provided a number of fractions within a maceral group region, some of these were also analysed. In a series of density fractions from a low rank vitrinite, it was found that the aliphatic hydrogen content decreased as the density increased. The inertinites also exhibited a decrease in aliphatic hydrogen. The inertinite C—O bands had extinction coefficients different from those of vitrinites or exinites. The data suggest that quite profound variations in organic structure as determined by FT-i.r. spectroscopy can exist within a maceral group, so that for the most critical work on coals it is necessary to take this into account. 相似文献
3.
Michio Shibaoka 《Fuel》1982,61(3):265-270
The behaviour of various huminite macerals and submacerals in a hydrogen-donor solvent, tetralin, at high temperature under hydrogen pressure was investigated. Small granular samples of three Victorian brown coals of different lithotype were treated with tetralin in two types of autoclave, at temperatures of 300–380 °C and under pressures of 5 or 10 MPa. The residual materials were investigated microscopically. This tetralin treatment caused huminite macerals and submacerals derived from highly gelified cellular material to become plastic even at temperatures as low as 340 °C, whereas it had no such effect on those derived from ungelified material. This relation between the degree of gelification and the tendency to become plastic during tetralin treatment in an autoclave is very similar to that found for vitrinite macerals and submacerals from bituminous coals. 相似文献
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应用红外光谱和电子顺磁共振对西曲煤显微组分的分子结构和自由基性质进行了研究。结果表明:镜质组、半镜质组和惰质组的芳碳率分别为0.84、0.91和0.93,镜质组分子结构单元中含有较多的脂肪取代基和螯形醌基;显微组分的自由基浓度(10~(18)spins/g):镜质组3.87,半镜质组18.98,惰质组40.10。镜质组自由基为较小的含氧型芳香π自由基,情质组自由基为巨大的纯芳香π自由基;半镜质组的分子结构和自由基性质均介于镜质组和惰质组之间。 相似文献
8.
西北侏罗系煤成油研究中的煤田地质学方法 总被引:9,自引:1,他引:8
运用煤田地质学方法分析、研究了西北侏罗系盆地的煤沼沉积环境演化类型(以下简称煤沼演化类型),划分出:①没有发育湖相建造;②含煤建造上覆缺失湖相建造;③具有完整湖平面变化旋四层序的三种煤沼演化类型;研究了西北侏罗系含煤盆地,尤其是第二和第三煤沼演化类型的煤显微组分组成和烃源岩的成熟度特征.根据西北侏罗系含煤盆地煤成油田形成和分布规律,依据煤沼演化类型、盆地沉积构造背景、有机岩组成特征等条件,提出了天山及其以北和塔里木周缘和祁连山两侧山前的前陆盆地等同沉积构造活动性较强的盆地是西北侏罗系煤成油勘探的有利区域,发育第一和第二煤沼演化类型的盆地及其伊犁和三塘湖盆地没有找到煤成油田的可能的看法. 相似文献
9.
煤岩显微组分离心分离实验的影响因素分析 总被引:1,自引:0,他引:1
结合煤岩等密度梯度离心分离技术(DGC)分离实验的原理,分析手选因素、解离因素、脱矿因素、重液密度等因素对分离实验效果的影响,以改进提高显微组分的分离纯度。 相似文献
10.
Thermobalance hydropyrolysis experiments are carried out on a highly volatile coal sample and its main macerals, vitrinite and exinite. The results are discussed according to the characterization of the tars using ultrasound solvent extractions, extrography, liquid chromatography, capillary gas chromatography and mass spectrometry. 相似文献