【作者】 岳晓明；

【导师】 魏贤勇；

【作者基本信息】 中国矿业大学 ， 化学工艺， 2012， 博士

【摘要】 加氢裂解反应是煤液化过程中关键的反应之一，高效催化剂的制备是煤炭液化中的核心技术。本课题用五氯化锑（PCA）和三氟甲磺酸三甲基硅酯（TMSTFMS）在微波辅助下单独浸渍和等体积复合浸渍于活性炭（AC）中，制备了3种负载型固体酸催化剂（PCA/AC、TMSTFMS/AC和PCA-TMSTFMS/AC），通过FTIR、SEM、EDS、BET、NH₃-TPD和XRD分析，发现PCA-TMSTFMS/AC具有强酸性，酸性明显强于另外两种固体酸，其中活性组分PCA、TMSTFMS和AC之间有着强烈的相互作用。以二（1-萘）甲烷（DNM）的加氢裂解作为探针筛，比较3种固体酸的活性和选择性。结果表明，3种固体酸均选择性地促进DNM中桥键的断裂和所生成1-甲基萘的脱甲基反应，但PCA-TMSTFMS/AC的催化活性远大于另外两种固体酸的催化活性。以PCA-TMSTFMS/AC作为新型固体酸（NSA），考察了反应温度和时间及氢气初压（IHP）和NSA用量对DNM加氢裂解的影响。发现随着反应温度及反应时间、IHP和NSA用量的增加，DNM的转化率增加，但IHP的提高对反应收率增加的影响较小。以胜利褐煤（SL）及其萃余物（SER）、灵武烟煤（LBC）及其萃余物（LER）、神府烟煤（SFBC）、胜利液化残渣（SLR）和黑山液化残渣（HLR）作为研究对象，NSA存在时在300oC时进行催化加氢裂解反应，用GC/MS定性和定量地检测反应混合物中的化合物类型和含量，将检测到的化合物进行族组分分析，并用无催化剂存在时、相同反应条件的加氢裂解反应作为对比实验，研究催化剂对煤及萃余物和液化残渣加氢裂解反应的影响。煤及萃余物和液化残渣的加氢裂解反应所得混合物（HCMs）的GC/MS可检测物以脂肪烃、芳烃和酚类以及醚类、酯类等含氧化合物为主，还包括少量的含N和S元素的化合物。在NSA催化作用下，煤及萃余物和液化残渣的加氢裂解反应收率均明显大于无催化剂存在下的反应收率，说明NSA对煤大分子结构中有机小分子的释放有着显著的促进作用。煤及萃余物和液化残渣的HCMs中芳烃和酚类含量都明显高于无催化剂时HCMs中芳烃和酚类含量，NSA对煤样中芳烃和酚类的生成有很大的促进作用，LBC和LER催化反应的HCM中芳烃和酚类增加最明显。煤及其萃余物的HCMs中检测到的芳烃的芳环数均小于等于4，而煤液化残渣的HCMs中芳烃含量比煤和萃余物的HCMs中芳烃种类和含量大的多，芳烃主要以4个及以上芳环为主，脂肪烃含量较少，说明SLR和HLR中稠环芳烃结构是煤液化残渣中的主体结构，大量的烃类等侧链结构在液化过程中被脱除。SER和LER的加氢裂解反应收率低于相应的原煤SL和LBC的反应收率，SER的反应收率低于LER，但NSA对SER加氢裂解反应收率的提高作用却比LER明显。在NSA存在下，用多种煤相关模型化合物作为反应物进行催化加氢反应，推测反应机理。烷基芳烃模型化合物的催化加氢反应结果表明，DNM、9-苄基菲（BP）、1-萘（9-菲）甲烷（NPM）和三苯甲烷（TPM）均发生了加氢裂解反应，生成了相应的Car–Calk键裂解所得产物，并生成芳环上加氢的产物，说明NSA能够高选择性地使C_ar–C_alk键断裂。烷基芳烃的反应性跟其超离域能值（Sr）和产物的自由基的共振能值（RE）大小有关。NSA有着很强的酸性和强吸电子能力，能够使H₂异裂为可移动的H⁺和吸附在NSA表面的H^-，H⁺转移到烷基芳烃的芳环取代位上，促使C_ar–C_alk键断裂。H⁺的生成是加氢裂解反应的关键步骤，H⁺转移到烷基芳烃的取代位上是发生加氢裂解反应的决定性步骤。苯基苄基醚（PBE）的催化反应说明NSA同样有促进醚桥键裂解的作用。由模型化合物的反应推测煤及其萃余物和液化残渣的加氢裂解反应机理，推测芳烃和酚类生成的反应历程。该论文有图55幅，表69个，参考文献174篇。更多还原

【Abstract】 Hydrocracking is one of the most important reactions for direct coal liquefaction.Preparation of catalysts with high activity is the core technology in the hydrocracking process.Three solid acid catalysts （NSA, PCA/AC and TMSTFMS/AC） were prepared by impregnatingthe same volume of pentachloroantimony （PCA）, trimethylsiyl trifluoromethanesulfonate（TMSTFMS）, or isometric PCA and TMSTFMA into an activated carbon （AC）. Through FTIR,SEM, EDS, BET, NH₃-TPD and XRD analyses reveal the strong interactions among PCA,TMSTFMA and AC in the NSA, and NSA exhibits appreciably stronger acidity than the othertwo catalysts. Di （1-naphthyl） methane （DNM） was used as a coal-related model compound toevaluate their catalytic activity. The DNM hydrocracking reactions show that Car-Calkbond inDNM can be selectively cleaved over each catalyst to afford naphthalene and1-methylnaphthalene under preesurized hydrogen at temperatures up to300oC, but as a newsolid acid, NSA is significantly more active for DNM hydrocracking than the other twocatalysts. The yield of naphthalene is appreciably higher tnan that of1-methylnaphthalene overany catalysts and the difference in yield between the two products increased with raising thereaction temperature, indicating that the1-methylnaphthalene demethylation proceeded andbecame significant at higher temperatures. DNM conversion, the product yields basicallyincreased with the increases in the NSA feed, reaction time and initial hydrogen pressure.Shengli lignite （SL）, Lingwu bituminous coal （LBC）, Shenmu-Fugu bituminous coal（SFBC）, Lingwu extraction residue （LER）, Shengli extraction residue （SER）, Shengliliquefaction residue （SLR） and Heishan liquefaction residue （HLR） were selected as theanalysis samples in the catalytic hydrocracking reactions with NSA at300oC. The productswere analyzed with GC/MS and were qualitative and quantitative analysis. The non-catalytichydroconversions （NCHC） were used as blanket experiments to compare with catalytichydroconversions （CHC） over NSA. Compared with the products from NCHC and CHC, itfound that NSA can highly promote the micromolecules to release from coals. The products ofhydrocracking reactions from the coal samples can be classified as alkanes, alkenes, arenes,phenols, esters, ethers, and other species organic compounds. The yields of arenes and phenolsof products from CHC were significant higher than that from NCHC. The number of aromaticring of arenes in products from raw coals and extraction coal residues is less than5, andphenols and naphthols are the main component of phenols in products from raw coals andextraction coal residues. The contents of arenes in products from coal liquefaction residueswere much higher that that from raw coals and extraction coal residues, and the number of the aromatic rings is mainly4and more than4. The content of aliphatic hydrocarbons in theproducts from coal liquefaction residues was less than that from raw coals and extraction coalresidues. Aromatic rings are the basic structure in coal liquefaction residues. Side chains ofaliphatic hydrocarbon were removed from liquefaction residues through the process ofliquefaction.The reactions of several coal relative model compounds show that NSA has highselectivity to cleavage of C_ar–C_alk bond, and the reaction reactivity depend on the superdelocalization energy （Sr） and resonance energy value （RE） of corresponding bond. Strongelectrophilic abilities and strong acidity of the NSA facilitates heterolytical splitting of H₂to animmobile H^-adhered to the NSA surface and a mobile H⁺. The mobile H⁺which added to theipso-position of arylalkanes to lead the cleavage of C_ar–C_alk bond. The generation of H⁺is thesignificant step of the hydrocracking reactions. The NSA also has the role to promote thecleavage of ether bridge bonds.There were55figures,69tables and174references in this paper.更多还原