未熟烃源岩低温催化脂肪酸酯生烃动力学研究

采用低温催化法研究未熟烃源岩催化脂肪酸酯生烃的动力学具有地质学上的实际意义。在模拟未熟油生成的地质条件下,选择十八烷酸甲酯作为模型化合物,以6种抽提有机质的未熟烃源岩作为载体,通过动力学的方法考察了未熟烃源岩矿物对脂肪酸酯生烃反应的催化作用。实验结果表明,在地质温度小于200℃的条件下,未熟烃源岩矿物催化脂肪酸酯生烃反应的活化能与碳酸盐含量、粘土总含量有一定的相关性。     

东营凹陷烃源岩低温催化酯水解生烃动力学研究

选用十八烷酸甲酯为模型化合物,以东营凹陷沙三和沙四烃源岩为载体,采用动力学方法考察了盐度、pH值、温度和压力对脂肪酸酯水解生烃反应的影响,求得了反应动力学参数.结果表明,烃源岩对脂肪酸酯水解生烃反应具有催化作用,与沙四烃源岩相比,沙三烃源岩作用下酯的水解反应活化能要大,这与烃源岩中的粘土含量有关.     

东营凹陷烃源岩低温催化酯水解生烃动力学研究

选用十八烷酸甲酯为模型化合物，以东营凹陷沙三和沙四烃源岩为载体，采用动力学方法考察了盐度、pH值、温度和压力对脂肪酸酯水解生烃反应的影响，求得了反应动力学参数。结果表明，烃源岩对脂肪酸酯水解生烃反应具有催化作用，与沙四烃源岩相比。沙三烃源岩作用下酯的水解反应恬化能要大，这与烃源岩中的粘土含量有关。     

未熟烃源岩低温催化单一酯与混合酯水解和生烃反应比较

选取胜利和江汉2个油田的未熟烃源岩为催化剂,以单一的十四烷酸甲酯、十六烷酸甲酯和十八烷酸甲酯以及它们的混合酯为模型反应物,分别进行相同条件下低温催化混合酯的水解及生烃模拟实验.结果表明:江汉、胜利2种未熟烃源岩低温催化单一酯的水解反应,水解率从大到小的顺序为:十四烷酸甲酯,十六烷酸甲酯,十八烷酸甲酯,而催化混合酯水解率大小则相反.催化单一酯与混合酯的生烃反应,生烃率从大到小的顺序均为:十八烷酸甲酯,十六烷酸甲酯,十四烷酸甲酯.由于混合酯中各种酯在未熟烃源岩表面上存在着催化活性位的竞争吸附,混合脂肪酸酯的水解率及生烃率都较单一脂肪酸酯的水解率及生烃率低.     

有机质对未熟烃源岩低温催化混合酯水解生烃的影响

选择十六烷酸甲酯和十八烷酸甲酯组成的混合酯为模型反应物,采用不同的方法对未熟烃源岩进行有机质抽提,以连串反应的动力学模型考察抽提前后未熟烃源岩低温催化混合酯水解率及生烃率的变化,分析有机质组分对催化反应的影响.结果表明:相比于抽提有机质后的未熟烃源岩,含有有机质的未熟烃源岩低温催化混合酯的水解率和生烃率更高.     

盐水对未熟生油岩中脂肪酸催化脱羧生烃的影响

选择十八烷酸为模型化合物,以辽河、江汉两种未熟生油岩为样品,在模拟地质条件（10MPa,160℃）下考察了浓度为10％的NaCl,KCl,MgCl2,Na2SO4等4种盐水及不同pH值的NaCl盐水对未熟生油岩中脂肪酸矿物催化脱羧生烃的影响。结果表明,对于辽河生油岩样,Na2SO4作用下的十八烷酸的矿物催化脱羧率最高,其次为KCl,NaCl,MgCl2。对于江汉生油岩样,KCl作用下4的十八烷酸矿物催化脱羧率最高,其次为NaCl,Na2SO4,MgCl2.pH值对十八烷酸矿物催化脱羧生烃有一定的影响,当pH=8时,十八烷酸脱羟率最高。这说明,在pH=8附近的碱性条件下,未熟生油岩对十八烷酸的脱羧生烃催化活性最大。模拟未熟生油岩的古沉积环境,对存在地层混合水时未熟生油岩对十八烷酸的脱羧生烃影响的考察结果表明,在pH＝8时,十八烷酸脱羧率最高,与单一盐类的影响规律相同。     

矿物低温催化脂肪酸或酯脱羧生烃的概述

矿物低温催化脂肪酸或酯的脱羧生烃是石油成因机制的一个重要方面。主要介绍一些矿物(尤其是碳酸盐)在低温条件下对脂肪酸或酯催化脱羧生烃的作用,从热力学方面说明矿物低温催化脂肪酸或酯羧羟生烃反应的活化能,从动力学方面说明矿物低温催化脂肪酸或酯脱羧生烃反应的机理。     

天然矿物低温催化脂肪酸酯水解反应动力学研究

选择十八烷酸甲酯为模型化合物,以10种天然矿物为载体,通过动力学方法考察了天然矿物对脂肪酸酯水解反应的催化作用。结果表明,地质低温条件下天然矿物对脂肪酸酯水解反应具有催化作用。粘土、碳酸盐和金属元素对于脂肪酸酯水解反应具有不同的催化作用。碳酸盐矿物相对于粘土矿物具有较低的催化水解反应活化能,过渡金属化合物矿物的催化反应活化能介于碳酸盐和粘土之间。     

盐水对未熟生油岩中脂肪酸催化脱羧生烃的影响

选择十八烷酸为模型化合物 ,以辽河、江汉两种未熟生油岩为样品 ,在模拟地质条件 (10MPa、16 0℃ )下考察了浓度为 10 %的NaCl,KCl,MgCl2 ,Na2 SO4 等 4种盐水及不同 pH值的NaCl盐水对未熟生油岩中脂肪酸矿物催化脱羧生烃的影响。结果表明 ,对于辽河生油岩样 ,Na2 SO4 作用下的十八烷酸的矿物催化脱羧率最高 ,其次为KCl,NaCl,MgCl2 。对于江汉生油岩样 ,KCl作用下的十八烷酸矿物催化脱羧率最高 ,其次为NaCl,Na2 SO4 ,MgCl2 。pH值对十八烷酸矿物催化脱羧生烃有一定的影响 ,当pH =8时 ,十八烷酸脱羧率最高。这说明 ,在 pH =8附近的碱性条件下 ,未熟生油岩对十八烷酸的脱羧生烃催化活性最大。模拟未熟生油岩的古沉积环境 ,对存在地层混合水时未熟生油岩对十八烷酸的脱羧生烃影响的考察结果表明 ,在 pH =8时 ,十八烷酸脱羧率最高 ,与单一盐类的影响规律相同     

可溶脂肪酸低温矿物催化生成甲烷的实验研究

将十八烷酸作为模型反应物，以改性蒙脱石，苏北和江汉油田未熟烃源岩岩样为催化剂，考察了在不同压力，温度下，脂肪酸低温催化加氢生成甲烷的能力，实验结果表明，温度，压力及矿物催化剂的结构对十八烷酸低温催化加氢生成甲烷有显著的影响，同时，在模拟地质条件下，未熟烃源岩中所含的可溶脂肪酸也能够生成一定量的甲烷，且水的存在对甲烷的生成有促进作用。     

Catalytic decarboxylation of fatty acid by iron-containing minerals in immature oil source rocks at low temperature

The catalytic activities of seven immature source rocks in China on fatty acid decar-boxylation for generating hydrocarbons have been evaluated by determinating the CO2 content from decarboxylation reaction of stearic acid. It has been found that the catalytic activities of immature source rocks mainly depend on the structure type of the minerals. In general, the catalytic activities of carbonates are higher than those of clays at low temperature. The higher its iron content, the higher the catalytic activity of carbonate.     

可溶脂肪酸低温矿物催化生成甲烷的实验研究

将十八烷酸作为模型反应物 ,以改性蒙脱石、苏北和江汉油田未熟烃源岩岩样为催化剂 ,考察了在不同压力、温度下 ,脂肪酸低温催化加氢生成甲烷的能力。实验结果表明 ,温度、压力及矿物催化剂的结构对十八烷酸低温催化加氢生成甲烷有显著的影响。同时 ,在模拟地质条件下 ,未熟烃源岩中所含的可溶脂肪酸也能够生成一定量的甲烷 ,且水的存在对甲烷的生成有促进作用。     

Simulation experiments for evolution of fatty acids in immature source rocks

The anhydrous, hydrous and bitumen-extrac- ted simulations were carried out for the immature source rocks from the Liaohe sag. It has been shown from the result that with increasing temperature in simulation experiments, the fatty acids content decreased at first and then increased. The decrease of fatty acids in immature rocks is presumably related to alkanes generation in immature oils, whilst the increase may be related to the fact that some additional fatty acids are generated from kerogen and the tightly bound fatty acids in kerogen are released as bound fatty acids in kerogen and unbound fatty acids in bitumen. The fact that the bitumen generated from kerogen contains fatty acids has demonstrated that some bound and tightly bound fatty acids in kerogen can be transferred into bitumen. The preferential fatty acids in the immature source rocks are found to be mono-carboxylic acids with longer chains, whilst krogen contains relatively more di-carboxylic acids. It has been found that the fatty acids in immature source rocks can be changed from that with more longer chains to that with more shorter chains when evolution extent has been increased. Based on simulation results and the fact that the majority of fatty acids in immature oils are those with longer chains, it is inferred that the contribution of fatty acids to forming alkanes in immature oils mainly takes place at the evolution stage with R₀ <0.6%. The simulation experiments have also demonstrated that H₂O could promote the generation of fatty acids with more di-carboxylic acids and delay alkanes formation from fatty acids.     

矿物低温催化脂肪酸酯在重水和水中的反应

分别以重水和水为反应介质进行对比实验,通过氢、氘核磁共振、红外光谱以及气相色谱等检测手段,对矿物低温催化十八烷酸甲酯的反应过程进行研究。结果表明：在模拟地质条件下,十八烷酸甲酯在D2O介质中的水解过程伴有少量氢氘交换,且氘转移主要发生在--OH基团上;十八烷酸脱羧生烃产物分布以正构烷烃为主,没有产生有分支的饱和烃,十八烷酸脱羧生烃反应具有自由基反应机理的典型特征。     

The occurrence of fatty acids in immature source rocks and their distribution characteristics

The fatty acids in extractable bitumen and kerogen of immature source rocks of the Liaohe Basin and Jiyang sag were investigated in this study. The result showed that the bitumen fatty acids were mainly associated with non-hydrocarbon fraction and that the kerogen fatty acids with some tightly bound fatty acids were mainly bounded in a net structure of kerogen by ester bonds. For the investigated source rocks, the fatty acids in bitumen, bound fatty acids and tightly bound acids in kerogen ranged in 0.01%—0.073.9%, 0.005%— 0.045 5% and 0.005%— 0.010% respectively. Among the fatty acids analyzed in this study, mono-carboxylic acids, a , w -di-carboxylic acids and hydroxy acids accounted for 70%—100%, 0%—30% and <10% respectively. It was also found that the mono-carboxylic acids with longer chains mainly existed in bitumen, and that the a , w -di-carboxylic acids and hydroxy acids mainly existed in kerogen. From above, it was assumed that the mono-car- boxylic acids in bitumen might have played an important role in the hydrocarbon generation from fatty acids in immature source rocks.