某些天然矿物质对煤液化催化加氢活性的研究

对中国某些天然矿物质以及一些冶金企业的精矿、尾矿和废渣的煤液化催化和加氢活性及其影响因素进行研究和探讨；并把它们与催化加氢活性较好的人工合成ＦｅＳ２进行了比较，以寻找适合于中国今后实现煤炭直接液化工业化可用的催化剂资源。     

铁系催化剂对煤高温快速液化的影响

以兖州煤为研究对象,采用微型反应釜研究了两种铁系催化剂对煤高温快速液化的影响.结果表明,担载Fe2S3的催化剂和高分散铁系催化剂对煤的热解行为影响较小;担载Fe2S3催化剂促进了氢气参与反应和煤液化产物向轻质化转化,在优秀和足量的供氢溶剂条件下,溶剂的供氢速度明显优于氢气转换的供氢速度,催化剂的作用不明显;对比添加高分散铁系催化剂并加助剂S和添加Fe2S3催化剂的煤高温快速液化,发现元素S的作用与S和主催化剂铁的结合形态有关.     

神府煤高温快速液化可行性的初步研究

用共振搅拌反应器研究了神府煤的高温快速液化的可行性 ,体系中如有足够的活性氢 ,短时间内可得到很高的转化率 ,高温快速液化是可行的 .与普通液化相比较 ,高温快速液化在490℃的 6min达到最佳转化率 ,大于普通液化 430℃ ,60 min的转化率 ,并且液化产物绝大多数是轻质物 ,可见高温快速液化降低了能耗 ,提高了过程效率 .     

依兰煤液化过程中天然矿物催化剂影响的研究

研究了黑龙江依兰煤在加氢液化反应过程中,4种天然含铁矿物的液化催化活性.试验结果表明,黑龙江西林铅锌矿的黄铁矿在依兰煤的加氢液化过程中,催化活性最高,萃取油收率达到68%,蒸馏油收率达到58%.     

煤的一段加氢液化的催化剂

煤的一段加氢液化使用的催化剂有可弃性催化剂,铁和钼氧化物及溶于水或油的催化剂和浸渍催化剂,其中以Co-Mo/Al_2O_3,Ni-Mo/Al_2O_3和钼酸铵为最广泛;黄铁矿能促进煤向油的转化,但却降低了脱硫率:Fe(OH)3-MoO_3-S在较低和较高温度下都是一种较活泼的催化剂;SnMo混合物明显优于纯SnO_2或无助催化剂的MoO_3/Al_2O_3;硫化的Mo(CO)_6是一种性能很好的煤加氢液化催化剂。     

煤直接液化催化剂研究进展

我国煤炭储量丰富,煤液化制油技术是缓解我国一次能源结构中原油供应不足的措施。煤液化工艺的各种催化剂中,铁基催化剂以其高效、廉价及低污染而倍受青睐。非铁系催化剂有Sn和Zn水溶液、含碘的煤液化催化剂、碱金属氢氧化物或碳酸盐、Cr-Mo-Ⅷ族的加氢催化液化催化和硫转移剂等。概述了近年来煤液化技术在铁系催化剂研究、回收利用、制备工艺和预处理等方面的研究进展,综述了煤液化催化反应器研究状况。     

超细FeS对五彩湾煤直接液化性能的影响

以硫酸亚铁为铁源,硫化钠为沉淀剂,采用液相沉淀法合成了超细FeS催化剂。以四氢萘为溶剂,反应温度430℃、氢初压6.0 MPa、反应时间60 min、溶煤比2∶1条件下,探讨超细FeS催化剂对五彩湾煤直接液化性能的影响。结果表明：硫酸亚铁基超细FeS粒子形貌均一,呈细棒状;五彩湾煤直接液化实验的油产率、液化率和转化率,以2.0%（wt,以活性金属元素计,相对于干燥无灰煤,下同）超细FeS为催化剂的实验分别达到56.15、73.29和81.21%（wt,相对于干燥无灰煤,下同）,高于相同条件下,以3.0%分析纯Fe2O3为催化剂的实验产率（分别是44.00、49.33和62.05%）。     

煤中矿物质在煤气化中的作用

本文以文献为基础,讨论了煤中矿物质对煤气化的催化作用、抑制作用、矿物质之间以及矿物质与外加催化剂的相互作用,提出在这一领域值得进一步研究的问题。     

Role of mineral matter in the chemical reactivity of coal

Previous work showed that the solvent extraction yield of coal increased as a result of chemical reactions such as formylation, reductive acylation, acylation, amidomethylation, alkylation, reduction and depolymerization. In the work described in this Paper, dmmf coal obtained after demineralization with mixed HF-HCI acids was used for solvolytic extraction studies after depolymerization, alkylation, acylation, amidomethylation, reductive acylation and reduction reactions. In comparison with the original coal, mineral matter free coal showed less increase in extractability as a result of these reactions indicating that mineral matter present in the original coal was acting as a promoter for these reactions.     

脱矿物质过程对煤结构影响的研究

选取神华煤和兖州煤两种煤样,用盐酸和氢氟酸处理脱去其中的矿物质,并且脱矿物质前后的煤样在氧化性气氛下,制成815℃的煤灰。利用红外光谱研究其矿物质组成以及处理前后煤结构的变化。结果表明：酸处理法能够脱除煤中大多数矿物质。2种煤灰中,矿物质组成主要是石英、硬石膏、方解石、高岭土和含铁矿物质,但含量不同。处理前后,煤结构中的含氧官能团发生了一定的变化。     

Analysis of sub-micron mineral matter in coal via scanning transmission electron microscopy

The fine-scale mineral matter in three US coals has been analysed via scanning transmission electron microscopy (STEM). The samples observed were a North Dakota lignite, a Kentucky bituminous, and a Pennsylvania semi-anthracite. Specific mineral types, differing among the three coals examined, appear to predominate at this fine size scale (particles ? 200 nm in diameter). Fe-rich and Ba-rich minerals in the lignite, a Ti-rich mineral in the bituminous and Ca-rich and Ti-rich minerals in the semianthracite were the predominant species found. The inherent mineral content in the observed organic background also differed from coal to coal. The distributions of mineral species in the size range ? 200 nm reported herein do not reflect the distributions in the larger size ranges obtained by more macroscopic techniques.     

Magnetic separation and thermo-magneto-chemical properties of coal liquefaction mineral participates

Sulphide solid particulates have been successfully separated from solvent-refined coal (SRC) liquid streams by high-gradient magnetic separation (HGMS) preceded by a sulphidation pretreatment in an H₂S-rich gaseous atmosphere. This pretreatment is derived from studies of the properties of dry sulphide residual liquefaction solids, treated in an atmosphere of various H₂/H₂S compositions. Procedures have been devised for promoting rapid conversion of the weakly magnetic hexagonal pyrrhotites to the more strongly magnetic monoclinic form at a temperature intermediate to those of the SRC dissolver and the magnetic separation stage.     

Hydropyrolysis of a high-sulphur-high-calcite Italian Sulcis coal. 2. Importance of the mineral matter on the sulphur behaviour

The sulphur distribution among the char, oil and gas obtained after hydropyrolysis of a high-sulphur (4.3 wt%) and high-calcite (7.3 wt%) coal has been investigated. The chars were examined by scanning electron microscopy coupled with an energy dispersion analyser and by X-ray diffraction. The proportion of the combustible and non-combustible sulphur in the char has been determined. Hydrogen pressure promotes reaction with sulphur but the sulphur content of the chars increases from 3 to 4.5 wt% when the temperature is increased from 616 to 845 °C. This increase in sulphur is a consequence of the reaction between hydrogen sulphide, produced during hydropyrolysis of coal, with the alkaline-earth mineral matter to produce alkaline-earth sulphide. The SEM and X-ray diffraction images show that in the char formed at 780 °C the sulphur, calcium and magnesium are localized in the same compounds. This is not the case when hydropyrolysis is performed at lower temperature. Combustion of the chars produces only <0.6 S0₂ MJ^?1 compared to 2.2 g S0₂ MJ^?1 for untreated coal. X-ray diffraction has shown that the sulphur in the char is oxidized and fixed in the ashes mainly as CaS0₄ and also some as MgS0₄. Although sulphur remains partly in the chars after hydropyrolysis, 75% of it is non-combustible. The hydropyrolysis of a high-sulphur coal containing calcite, produces a char which may be used as a clean fuel.     

Reduction of iron sulphates during coal liquefaction

The transformation of pyrite to pyrrhotite and gypsum to anhydrite is well known during coal liquefaction. Most coals, except extremely fresh ones, contain various iron sulphates resulting from the oxidation of pyrite and marcasite. The reduction of iron sulphates to pyrrhotite during liquefaction is shown with the degree of reduction being temperature dependent. The formation of pyrrhotite from the iron sulphates is important because pyrrhotite is considered to catalyse hydrogénation reactions.     

Mineral matter effects on the rapid pyrolysis and hydropyrolysis of a bituminous coal. 1. Effects on yields of char,tar and light gaseous volatiles

The effects of minerals on product compositions from rapid pyrolysis of a Pittsburgh Seam bituminous coal were investigated. Whole, demineralized, and mineral treated samples of pulverized coal were heated in 100 KPa helium or 6.9 MPa hydrogen at 1000 K s^?1 to temperatures of up to 1300 K. Yields of char, tar and individual gaseous products were determined as a function of time-temperature conditions. Clays, iron-sulphur minerals, and quartz had few effects on pyrolysis in helium. Calcium minerals decreased yields of hydrocarbon products and increased yields of CO in helium pyrolysis. Calcite and clays decreased yields of CH₄ from hydropyrolysis, whereas iron-sulphur minerals had little effect on pyrolysis at 6.9 MPa H₂. Whole coal results were similar to demineralized coal results under all conditions.     

Characterization and catalytic activity of coal mineral matter: 1. Effect of hydrogen pretreatment and exposure to sulphur and nitrogen compounds

Low temperature ash (LTA) samples prepared from nine US coals were characterized by X-ray diffraction. X-ray fluorescence, and surface area analyses. The results showed that illite, kaolinite, quartz and pyrite are major components in LTAs and that $\text{S}\text{Fe}$ ratios of some LTAs decreased significantly after H₂ treatment implying the occurrence of a partial reduction of pyrite during this treatment. Surface areas of LTAs increased drastically on H₂ treatment but decreased after exposure to sulphur and nitrogen compounds in activity testing. Correlations for the surface areas of LTAs before and after H₂ treatment were found in terms of clay content and element concentrations.     

Data on low rank coal liquefaction from DRIFT analysis

A Spanish low rank coal was hydrogenated without solvent in the presence of a molybdenum catalyst. The asphaltenes and derived residues were analysed to obtain an understanding of the behaviour of the coal under hydrogenation conditions and the influence of a previous extraction with chloroform, as well as reaction time and temperature, on the structure of the products obtained. Under the reaction conditions used, with tubing bomb reactors and an initial hydrogen pressure of 7 MPa, the data obtained for this coal show that an increase in temperature from 350 to 400 °C, and of reaction time from 5 to 60 min gives, in general, lower content of organic matter in the residues. The two variables have opposing effects on the aromatic content of the asphaltenes. Increasing reaction time reduces the aromaticity, whereas increasing the temperature will increase aromaticity. Prior extraction of the low molecular weight chloroform-soluble compounds increased conversion, and resulted in asphaltenes with higher content of aromatic- and oxygen-containing groups.