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11.
A novel carbon foam with high strength and very low thermal conductivity was prepared by thermal treating of coal tar based mesophase pitch mixed with montmorillonite clay. SEM observation showed that less micro-cracking appeared on the cell wall of foam by adding of clay-montmorillonite. Foam mechanical properties were improved and its thermal conductivity was markedly decreased. The compressive strengths were increased by 64%, 96% and 100% when the additive amounts of clay were 2%, 5% and 10% (wt%), respectively. Due to the high thermal insulation and lamellar structure of clay, the thermal conductivity of carbon foam decreases from 2 W/m K to 0.25 W/m K. 相似文献
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13.
热溶过滤法脱除煤焦油沥青中喹啉不溶物的研究 总被引:3,自引:1,他引:3
以5种煤焦油沥青为原料,喹啉为溶剂,研究了热溶过滤法脱除喹啉不溶物(QI)等杂质的效应,目的是制备QI含量较低的净化沥青。结果表明:热溶过滤法可以有效地脱除喹啉不溶物,QI脱除率随滤网网目增加而提高,但阻力增加,脱除时间变长。综合考虑脱除率和实际可操作性,采用1000目的滤布,QI含量可以降到0.3%以下,基本能达到要求。采用凝胶色谱对QI脱除后沥青的组成和分子量分布的研究表明,热溶过滤脱除了沥青中的大分子组分,分子量减小,分子量分布变窄。 相似文献
14.
DMF法丁二烯抽提装置第二萃取塔的结焦堵挂问题一直是制约装置长周期运行的主要因素,胶状聚合物的生成、焦油状物质的析出等都会造成第二萃取塔堵挂,影响装置的长周期稳定运行,本文从生产实际出发,对导致第二萃取塔堵挂的因素进行剖析,并提出相应的解决措施。 相似文献
15.
13C n.m.r. spectroscopy has been applied to investigate a number of coal tar and petroleum-derived carbon black feedstocks. Application of the J-modulated spin echo technique is especially rewarding, as this method renders the quaternary carbons directly detectable. Thus the quality of carbon black feedstocks can additionally be gauged on the basis of the contents of quaternary carbons, which is a direct indication of the carbon yield in the carbon black production process. 相似文献
16.
我国煤焦油加工的现状及发展趋势 总被引:6,自引:0,他引:6
我国煤焦油加工的现状为:装置规模小;热能回收利用不合理;产品种类少;环境保护存在一定问题。从国内外焦炭市场和生产情况分析,认为我国机焦产量大幅增长是带动煤焦油加工业发展的主要因素。指出我国煤焦油集中加工格局已经形成.时机已经成熟。 相似文献
17.
This paper deals with the study of the variation of properties of four pitches (a commercial impregnating coal tar pitch, an air-blown and two thermally treated pitches) when mixed with four granular carbons (anthracite, graphite, green petroleum coke and foundry coke). As a first step, optical microscopy was used to determine the distribution of the pitch among the granular carbons. The anthracite seems to attract the primary quinoline insolubles present in the commercial and thermally treated pitches. This allows the mesophase spheres to coalesce at unusually low temperatures during the mixing process. In general, the toluene insoluble content of the pitch showed a significant increase after mixing with the granular carbons. This is an indication of the interactions between the different granular carbons and some compounds present in the pitches. Analytical techniques like size exclusion chromatography and differential scanning calorimetric analysis were used in order to obtain information about the characteristics of the components of the pitches that interact with the different granular carbons and their effect on pitch properties. Graphite seems to interact preferentially with the larger molecules whereas the green petroleum coke acts on a wider molecular range. 相似文献
18.
混合溶剂法脱除软沥青的喹啉不溶物 总被引:2,自引:0,他引:2
煤沥青中含有较多的喹啉不溶物会影响炭材料的性能。以软沥青为原料,采用混合溶剂离心法对其进行脱除喹啉不溶物试验研究。考察了芳烷比、溶剂比、离心时间、离心温度对精制沥青的喹啉不溶物含量和收率的影响。结果表明:当芳烷比一定时,精制沥青喹啉不溶物含量和收率随溶剂比的增大而减小;当溶剂比一定时,精制沥青喹啉不溶物含量和收率均随芳烷比的增大而增加;离心时间越长,所得精制沥青喹啉不溶物含量越低,收率也越低;离心温度升高,有利于喹啉不溶物脱除,离心温度的较优选择为80℃。通过调整混合溶剂的比例,可以方便地控制净化过程的收率和喹啉不溶物含量。 相似文献
19.
Branched-chain/cyclic alkanes have been obtained, by solvent extraction and molecular-sieve adsorption, from a UK low-temperature (Rexco) coal tar, a USA fluidized-bed pyrolysis (FMC COED) coal tar, and a novel supercritical-gas-extract of a Turkish (Elbistan) lignite. Mass spectrometry (with gas chromatography and field-desorption) established the presence of mono-, di (including sesquiterpanes), tri-, tetra- (steranes only), and pentacyclic (triterpanes only) alkanes, including several steranes and triterpanes not previously reported as coal-tar constituents. The potential of cyclic alkanes as geochemical markers, even for commercial coal products subjected to appreciable heat treatment, is demonstrated by the identification of C12, C13, C15 and C16 dicyclics (including isoprenoid alkanes), C17-C26 tricyclics, and C27 and C29 hopane-type pentacyclics (triterpanes) in FMC, and of C16-C38 monocyclics, C34-C36 dicyclics, C22-C36 tricyclics, C27-C30 tetracyclics (steranes), and C27, C29, C30, C31, C32, and C33 hopane-type pentacyclics (triterpanes) in Rexco tar. Tetra- and pentacyclic alkanes were also preserved in the lignite extract. 相似文献
20.
以中低温煤焦油沥青(MLTCTP)为原料,正庚烷、甲苯和喹啉为萃取剂,采用索氏抽提法分离得到:庚烷可溶物(HS)52.39%,庚烷不溶甲苯可溶物(HI-TS)43.9%,甲苯不溶物3.71%,不含喹啉不溶物。采用元素分析、相对平均分子量、红外光谱、紫外光谱和1 H-NMR等表征方法对中低温煤焦油沥青及其族组成的分子结构进行了研究。结果表明:MLTCTP、HS及HI-TS的相对平均分子量分别为326.5、258.4和361.6;平均分子式分别为C22.74-H22.47N0.249S0.055O1.53、C18.79H22.94N0.083S0.056O0.70和C24.48H21.74N0.387S0.063O2.33,其中杂原子氧主要以Ar-OH结构存在;MLTCTP的平均分子结构是以线性排列为主、面性排列为辅的四环稠环结构,HS平均分子结构为两单苯环线性链接结构,HI-TS的平均分子结构是以面性排列为主的五环稠环结构。 相似文献