Processing of byproducts from carbonisation of non-caking coals: recovery of tar acids

Recovery of tar acids from ammoniacal liquor and middle oil fraction (170–270°C) of tar produced in the Woodall–Duckham type carboniser of Dankuni Coal Complex (DCC), using non-caking coals, has been investigated. About 99.5% of the phenols contained in ammoniacal liquor can be extracted with isobutyl acetate in five stages of extraction using a feed:solvent ratio of 8:1 (v/v) and the phenols content of the liquor can be reduced from about 6000 to 30 ppm. A comparison of products obtained from tar distillation under laboratory conditions to those under actual plant operation has been made. The optimum yields of the middle oil, under standard laboratory distillation and tar distillation plant, were 27.12% and 22.5%, respectively, on dry tar and the content of the refined tar acids in these oil fractions were found to be 9.35% and 7.6% (on dry tar), respectively. However, in actual plant practice, this level of yield has not been achieved yet, due to loss of substantial quantity of tar acids in processing units. With a view to optimising the yield, various aspects of plant operation and process streams were investigated. The yields of tar acids and the other processing streams of DCC have been compared with those of metallurgical coke plants and variations in composition of tar acids discussed. The dihydric phenols (ca. 16% of tar acids) obtainable from DCC, have been shown to offer an attractive potential. The environmental aspects related to discharge of waste streams have been dealt with.     

下行床煤拔头工艺的产品产率分布和液体组成

基于循环流化床锅炉燃烧技术和下行床技术相结合,在处理能力为8 kg/h的煤拔头工艺热态实验装置上,以内蒙古霍林河褐煤为原料,普通河砂为固体热载体,考察了反应温度和煤粉粒径对气液固产品产率分布和液体组成的影响规律. 结果表明,在实验温度范围内,随着温度的升高,气体和液体产品的产率增加;液体产率随粒径的增大而降低. 当反应温度为660℃、煤粉粒径小于0.28 mm、加料率为4.7 kg/h时,轻质焦油(焦油中的正己烷可溶物)的产率可达7.5%(干煤基,w),其中酚类占57.1%,粗汽油(脂肪烃类)占12.9%,芳香烃占21.4%,极性组分和其他组分占8.6%. 实验表明,下行床由于气固沿重力场并流向下流动的特点,是适合煤拔头工艺的比较理想的反应器.     

提高酚产品收率的几点措施

酚产品收率低的主要原因是：焦油加工车间酚油和素油的酚集中度低、馏分碱洗脱酚和废水萃取脱酚过程中乳化物多；酚盐分解时一些挥发酚进入大气；粗酚精制后酚渣中遗留的二甲酚和高级酚大多。要提高焦化企业的酚收率，除改进工艺制度及认真操作外，还要严格控制入萃取塔的废水质量及焦炉循环氨水质量。同时，应尽量完善设施，诸如设立酚盐分解酸汽吸收塔、酚渣蒸馏等装置。     

稻壳快速热裂解生物油的特性研究

Physicochemical properties of bio-oil obtained from fast pyrolysis of rice husk were studied in the present work.Molecular distillation was used to separate the crude bio-oil into three fractions viz.light fraction,middle fraction and heavy fraction.Their chemical composition was analyzed by gas chromatograph and mass spectrometer(GC-MS).The thermal behavior,including evaporation and decomposition,was investigated using thermogravimetric analyzer coupled with Fourier transform infrared spectrometer(TG-FTIR).The product distribution was significantly affected by contents of cellulose,hemicellulose and lignin.The bio-oil yield was 46.36%(by mass) and the yield of gaseous products was 27%(by mass).The chemicals in the bio-oil included acids,aldehydes,ketones,alcohols,phenols,sugars,etc.The light fraction was mainly composed of acids and compounds with lower boiling point temperature,the middle and heavy fractions were consisted of phenols and levoglucosan.The thermal stability of the bio-oil was determined by the interactions and intersolubility of compounds.It was found that the thermal stability of bio-oil was better than the light fraction,but worse than the middle and heavy fractions.     

Solvent extraction study of a whole,low-temperature tar

A low-temperature tar was sub-divided, entirely by solvent extraction, into the following fractions: crude phenols and bases; hydrocarbons of different types—aliphatic, hydroaromatic and aromatic; and a neutral, oxygen-containing aromatic fraction. The three hydrocarbon materials and the last-named were obtained from the neutral tar oil (light petroleum-soluble) by a series of partition extractions with the solvent pair, furfural/light petroleum, petroleum, using definite ratios of tar/solvents. These four fractions corresponded closely to those previously obtained by adsorption chromatography.     

低温煤焦油粗酚精制过程优化

用气质联用仪分析低温煤焦油中粗酚的组成与含量,利用Aspen Properties软件估算并评价非库组分的主要物性和多元交互作用参数,借助Aspen Plus软件模拟优化四塔联用减压精馏过程,并对上述最佳操作条件的可靠性进行验证. 结果表明,粗酚共检出23种酚类化合物,占97.806%,低级酚含量较高,约为89.436%,高级酚种类多而含量低;非库组分的估算结果能满足后续模拟计算的准确度要求;精馏苯酚塔、邻甲基苯酚塔、对/间甲基苯酚塔、二甲基苯酚塔的最佳塔板数为90, 80, 70, 60,最佳进料口位置为55, 30, 39, 32,最佳回流比为15.52, 15.95, 15.87, 0.98;塔顶苯酚、邻甲基苯酚、对/间甲基苯酚和二甲基苯酚产品的平均纯度和收率均满足规定要求.     

中低温煤焦油中酚类化合物的柱层析分离

以陕北中低温煤焦油重油170℃²40℃馏分酚油为原料,考察硅胶柱层析对酚类化合物的分离效果。按照洗脱剂极性从小到大次序,依次使用11种洗脱剂进行洗脱,将洗脱出的溶液进行GC/MS分析,结果表明:硅胶柱层析在各种洗脱剂的洗脱下,分别得到了从高级酚到低级酚的酚类化合物分布,在正庚烷与乙酸乙酯(10:1)混合溶剂、正庚烷与乙酸乙酯(1:1)混合溶剂洗脱下,均得到了低级酚的混合物;在正庚烷与乙酸乙酯(1:10)混合溶剂洗脱下,得到了苯酚单一的化合物。通过实验分析可知,柱层析分离方法是中低温煤焦油中酚类化合物分离的有效途径之一。     

Sulfidation of the concentrates of 5-methyltresorcinol with elemental sulfur

The interaction of elemental sulfur with the shale dihydric phenols aimed at the synthesis of monoand polythio-(bis)alkylresorcinols has been studied. We have performed preliminary experiments on the preparation of these products based on the concentrates of 5-methylresorcinol with the content of the base material from 52 to 91 wt %.     

Catalytic hydrodealkylation of tar acids

The catalytic vapour phase hydrodealkylation of LT tar acid fractions to low boiling phenols was studied in a flow system in the temperature range 480–650°C, and over a wide range of space velocities on a chromia—alumina catalyst at atmospheric pressure. The feed, as well as the products, was analysed by gas chromatography. Optimum conditions for maximum yield of lower phenols were established. In the hydrodealkylation of tar acid fractions (i) b 170–210°C, (ii) b 210–230°C and (iii) b 230–270°C, the contents of lower phenols in the liquid products were found to be respectively, 98.6% (55.2 % phenol + 43.4% cresols), 85.5.% (27.4% phenol + 58.1% cresols) and 79.9% (26.8% phenol + 53.1% cresols) at 600°C. The catalyst was found to be highly specific in eliminating the dehydroxylation of phenolic substrates. The physico-chemical properties of the catalyst were determined. Based on an examination of the nature of the catalyst and the product pattern, a tentative mechanism for the reaction has been postulated. The results are interpreted as being due to the formation of chemisorbed phenoxy radicals and their subsequent reaction at the surface of the catalyst.     

半焦基催化剂裂解煤热解产物提高油气品质

利用上段热解下段催化的两段固定床反应器,针对府谷煤研究了半焦和半焦负载Co催化剂对煤热解产物的催化裂解效果。结果表明,半焦和半焦负载钴对热解产物催化裂解后,热解气收率增加,焦油收率降低,但焦油中沸点低于360℃的轻质组分含量提高,轻质焦油收率基本保持不变或略有增加。与煤在600℃直接热解相比,在热解和催化温度均为600℃,采用煤样质量20%的半焦为催化剂时焦油中轻质组分质量含量提高了约25%,轻质组分收率基本不变,热解气体积收率增加了31.2%;在热解温度600℃,催化温度500℃时,采用煤样质量5%的半焦负载钴催化剂,焦油中轻质组分质量收率和含量分别提高了约8.8%和28.8%,热解气体积收率增加了21.5%。煤热解产物的二次催化裂解的总体效果是将焦油中重质组分转化为轻质焦油和热解气。     

Hydrogenolysis and hydrocracking of the carbonoxygen bond. 3. Thermolysis in tetralin of substituted anisoles

Mild pyrolysis and hydrogenolysis products of coal contain substantial amounts of pyrocatechol and resorcinol and their homologues whereas hydroquinone and its homologues are absent or present in only low amounts. In the present work the model compounds anisole and methyl-, methoxy- or hydroxy-substituted anisoles were studied to elucidate substituent effects on the carbon—oxygen bond cleavage in the presence of tetralin. The experiments were carried out at 618 K and 6 MPa (H₂). The major reaction is demethylation to the corresponding phenols. A steric effect can be seen in the ortho compounds and an electronic effect when the substituent is a strongly electron-releasing group. In compounds with oxygen substituents para to each other little or no hydroquinone can be isolated whereas the ortho and meta compounds, respectively, give pyrocatechol and resorcinol. It is suggested that the low yield or absence of hydroquinone in this work and in coal pyrolysis is due to the high reactivity of the intermediate p-hydroxyphenoxy radical, which gives rise to adducts and other compounds of high molar mass. The ortho radical is sterically hindered and the meta radical has a lower reactivity and are hence abstracting hydrogen from the hydrogen donor or coal.     

Separation and Purification of Indole in Model Coal Tar Fraction of 9 Compounds System

Separation and purification of indole present in model coal tar fraction was examined by the combination of extraction to separate indole from the crude model coal tar fraction, distillation to obtain high concentration of indole in the extract, and solute crystallization (SC) to obtain high-purity indole present in indole-enriched distillate. The model fraction was made up of four types of nitrogen heterocyclic compounds (quinoline, iso-quinoline, 4.66% indole, and quinaldine), three types of bicyclic aromatic compounds (1-methylnaphthalene, 2-methylnaphthalene, and dimethylnaphthalene), biphenyl, and phenyl ether. Aqueous solutions of formamide and n-hexane were used as the extraction solvent and the SC solvent, respectively. Through the combination of formamide extraction, distillation, and SC using n-hexane in this work, 99.5% indole was recovered. We confirmed that the combination examined by this work was one of the very useful combinations for the high-purity purification of indole present in the coal tar fraction.     

Methanesulfonic acid catalyzed additions to oleic acid and cyclohexene. III. Addition of acids and substituted phenols

Benzoic acid adds to oleic acid in methanesulfonic acid as catalyst-solvent to form an addition product in 30% yield. Saponification studies on the product reveal that the addition is made via the carboxyl group and no rearrangement of the initial product takes place. A number of substituted benzoic acids were also tried but the yield of addition product was nil. Data are included for the experiments with a number of phenols not previously reported. These include: o-chlorophenol,2,6-di-tert.-butylphenol, 2,4,6-trichlorophenol, resorcinol, 5-n-pentadecylresorcinol, hydroquinone, methyl salicylate, and 3-n-pentadecylphenol. Good yields of addition products of cyclohexene are obtained using methanesulfonic acid as catalyst-solvent and the same nucleophiles employed previously. Presented at the AOCS meeting in Toronto, Canada, 1962. A laboratory of the E. Utiliz. Res. & Dev. Div., ARS, U.S.D.A.     

Application of silver-based dihydric alcohol to the extraction of methyl linolenate with high extractability and stability replacing ionic liquids

A novel silver-based dihydric alcohol extractant was substituted for ionic liquids to enrich methyl linolenate (C18-3) from tallow seed oil methyl ester in this study. The interactions among dihydric alcohol, Ag(I) and C18-3 were explored by FT-IR spectroscopy. The effects of dihydric alcohol structure, carrier Ag (I) concentration, temperature and initial feed concentration on extraction yield and selectivity were reported. The good extraction performance was achieved by 1,4-butanediol containing AgBF₄. The complexation of Ag (I) with C18-3 was dominant in extraction operation rather than physical partition. Furthermore, a multi-step reverse extraction method was proposed to obtain C18-3 product and regenerate the extractant. 1-Hexene as the stripping phase can facilitate C18-3 reverse extraction. The content of C18-3 in the product was up to 93.36%, and the yield was 73.76%. This work opened a new route for the utilization of the dihydric alcohol properties to manipulate the carrier efficiency for extracting unsaturated fatty acid methyl esters at a lower cost.     

一种低温煤焦油混合酚钠盐的分解新方法

低温煤焦油含有苯酚、甲酚、二甲酚等几十种多取代苯酚类化合物,提取苯酚类化合物现有两种方法,最常用的酸碱法虽简便,但产生大量废酸、废碱,会污染环境、腐蚀设备等;溶剂萃取法污染较少,但操作复杂,成本增加,并降低剩余煤焦油加氢制燃料的收率。本文介绍了一种低温煤焦油混合酚钠盐的分解新方法,采用由两个双极性膜和一个阳膜为基本单元构成的双极膜电渗析装置,分解混合酚钠盐,生成混合苯酚化合物。可以有效解决传统煤焦油加工技术中大量酸、碱废水的排放,是一项绿色化学工艺技术。     

Characterization of the Organic Matter of Humic Acids by Pyrolytic Gas Chromatography–Mass Spectrometry

The results of the pyrolytic analysis of products of the organic matter of Sphagnum fuscum, fuscum peat, and humic acids separated from peat with the use of pyrolysis–chromatography–mass spectrometry in the Rock-Eval version are presented. It was shown that Sphagnum fuscum and peat differed only slightly in the degrees of chemical transformation. Benzene, phenol, and their alkyl-substituted homologues predominated in the thermal desorption products of humic acids upon pyrolysis to 400°C. Acetic acid, monohydric phenols, syringol, and guaiacol, which are the basic compounds in the high-temperature fraction, were formed on the pyrolysis humic acids to 700°C from the carbohydrate, phenylpropionic, and guaiacylpropane structural fragments.     

间热径向流反应器料层厚度对煤热解特性的影响

考察了方形径向流固定床煤热解反应器中变化煤层厚度对料层升温速度及煤热解产物分布特性的影响。随着料层厚度增加,导致煤热解反应要求的时间增长,热解水和气的产率相应增加,焦油和半焦收率逐渐降低,但焦油中轻质组分(沸点低于360℃组分)含量呈升高趋势,半焦和煤气热值稍许降低。如,加热壁温度900℃、从45 mm至105 mm增加煤料层厚度时,焦油产率从7.17%(质量,下同)下降到6.26% (相对干基煤),但焦油中的轻焦油组分含量则从67%升至72.7%,半焦产率由80.0%降至77.0%,热解水和煤气产率分别由6.96%和5.91%增至8.85%和7.90%,煤气热值则由24348.5 kJ·m^-3下降至20649.2 kJ·m^-3。所得半焦的热值径向上由高温侧向低温侧逐渐降低,煤料层越厚、热值降幅越大,而相同煤料层厚度处与加热壁平行的同一轴向平面上的半焦热值基本相同。针对研究的反应器,气相热解产物在反应器内沿径向(横向)由高温料层区向低温料层区流动。在该过程中伴随着热解产物对远离加热壁的低温煤料的传热、热解生成重质组分的冷凝和在煤/半焦颗粒表面的吸附截留,进而在低温料层进一步升高温度时发生二次裂解等物理化学过程。反应器内煤层厚度越大,上述各种伴随的物化作用越显著,从而明显影响煤料层的升温及热解特性。     

Structural Basis for Intumescence – Part III – Thermal Degradation Study of Intumescent Polymers Containing Spirophosphorus Moiety in the Backbone

3,9-Dichloro-2,4,8,10-tetraoxo-3,9-disphosphaspiro-[5.5]-undecane-3,9-dioxide (spiro) was melt condensed with structurally different dihydric phenols to form poly aromatic spirophosphates. The thermal volatilization analysis showed eruptive release of gases above 300°C and the temperature region of release depends on the nature of the aromatic units incorporated in the polymer backbone. The thermal degradation in nitrogen atmosphere indicated the formation of phenol, substituted phenols, aromatics, alkyl and alkenyl substituted aromatics and condensed aromatics like azulenes, indanes and fluorenes. The source for the formation of these products is the spiropentadiene released from the spiro unit during degradation.     

双循环反应系统中麦饭石催化提质生物质热解挥发分

以麦饭石作为催化提质床料,在双循环反应系统中进行了生物质快速热解挥发分的催化提质实验,考察了麦饭石提质床料、催化提质温度和提质循环速率对生物质快速热解产物的影响。和石英砂相比,麦饭石催化提质降低了焦油产率,但提高了焦油中轻质焦油的相对含量。同时,麦饭石促使生物油中的氧元素以H₂O、CO和CO₂的形式脱除,且主要以H₂O和CO的形式脱除,使焦油中烃类、酚类含量显著增大,酸类、酮类物质含量显著降低。催化提质温度升高更有利于焦油中的氧以H₂O和CO形式脱除,焦油中烃类相对含量随提质温度升高而增加,而酸、酯、酮类含量降低。提高催化提质循环速率,焦油中轻质组分相对含量增加,但焦油中烃类、酚类相对含量均降低。在提质温度520℃,提质循环速率5.5kg/h时,提质油品质较好,轻质焦油含量较高,酚类物质相对含量可达到46.37%。     

磷酸酯齐聚物阻燃剂的合成及应用

以三氯氧磷、间苯二酚、双酚A和苯酚等为原料合成了间苯二酚型磷酸酯齐聚物和双酚A型磷酸酯齐聚物，其结构经红外光谱、高效液相色谱和热重分析表征。研究了催化剂种类和用量对反应的影响以及反应物配比和溶剂对产物性能的影响，结果表明，MgCl2的催化效果最好，最佳用量为1％，三氯氧磷与双酚类化合物的最佳摩尔比为1：4．5-5．0。磷酸酯齐聚物阻燃剂在树脂阻燃方面的应用实验表明，其对聚碳酸酯、聚苯醚、聚苯醚倩抗冲聚苯乙烯和聚对苯二甲酸丁二醇酯的阻燃可达到UL94 V-0级。