咪唑类离子液体辅助溶剂萃取油砂沥青研究

采用阴离子为BF₄^-,阳离子为1-烷基-3-甲基咪唑类的离子液体（Ionic Liquids,ILs）辅助丙酮/正庚烷复合溶剂和甲苯2种溶剂萃取加拿大油砂中的沥青,考察了ILs辅助2种溶剂萃取油砂沥青过程中,ILs阳离子咪唑环一取代位上的碳链长度对沥青萃取率和固体夹带的影响。实验结果表明,随着ILs阳离子咪唑环一取代位上碳链的增长,沥青的萃取率总体逐渐降低。碳链从甲基变化到正己基,在丙酮/正庚烷复合溶剂体系中,沥青萃取率由9.29%降到8.55%;在甲苯体系中,沥青萃取率由10.05%降低到9.45%。但在2种体系中,加入碳链为正丁基的IL的沥青萃取率高于碳链为正丙基的IL。采用红外光谱对不同萃取体系中所萃出的沥青相进行分析发现,纯甲苯萃出的沥青相中检测到砂砾物质,而6种ILs辅助甲苯所萃取出的沥青中的砂砾含量则在红外检出限以下。丙酮/正庚烷复合溶剂及在6种ILs辅助下萃出的沥青相中均未检测到细小砂砾物质。实验结果为如何筛选适当ILs应用于非常规石油分离提供了科学基础。     

阳离子聚丙烯酰胺辅助溶剂萃取油砂沥青工艺研究

使用甲苯、正庚烷、石油醚和石脑油,辅以阳离子聚丙烯酰胺和离子液体等助剂对加拿大亲水型油砂进行了萃取实验,并从沥青回收率、沥青中细沙夹带和残砂形貌3个角度对沥青分离效果进行了分析评价,最终认为阳离子聚丙烯辅助石脑油萃取油砂沥青是一种经济可行的工艺路线。随后文章从助剂浓度、助剂存放时间、助剂和油砂比例、溶剂和油砂比例等角度出发,对工艺参数进行了优化。结果表明,在室温条件下,当石脑油：0.05% CPAM水溶液：油砂为3：2：1时,沥青回收率由72.29%提升至78.29%。此外,通过对沥青的红外分析和残砂的扫描电镜分析还发现,阳离子聚丙烯酰胺在甲苯和石脑油萃取体系中均有夹带减小细砂的功效。     

克拉玛依油砂溶剂萃取分离实验研究

以克拉玛依油砂为实验对象,考察石油醚、环己烷、正戊烷、正庚烷、甲苯、CS2及复合溶剂EOSA萃取分离油砂沥青的效果,确定EOSA为最佳萃取溶剂。研究了温度、溶剂用量、时间对EOSA萃取分离油砂沥青收率的影响。结果表明,在萃取温度30℃、剂砂比2 mL/g条件下萃取30 min,油砂沥青的收率可达95%以上。再生实验结果表明,在60~80℃条件下,溶剂回收率超过99%。该工艺具有无水参与、零排放、低能耗、高收率等优点。     

离子液体促进溶剂萃取油砂沥青

传统水洗法和溶剂萃取法萃取油砂沥青时,存在沥青中含有沙土和残沙中含有油等缺点。为解决上述缺点,本文采用不同比例的乙酸甲酯/正庚烷复合溶剂萃取油砂沥青,研究了离子液体（1-丁基-3-甲基咪唑四氟硼酸盐,[Emim]BF4）对该溶剂萃取体系的萃取率和分离洁净程度的影响。采用红外光谱仪和扫描电镜对萃取后的残沙和沥青的洁净程度进行了定性分析,并结合元素分析仪和电感耦合等离子体发射光谱仪获得萃取后残沙和沥青的洁净程度的定量结果。实验结果表明：当复合溶剂体积比为2∶3时,[Emim]BF4促使沥青回收率达到最大值94.20%,比单纯复合溶剂萃取体系的最大萃取率高7.92%;通过上述测试方法的定性和定量分析,证明了[Emim]BF4能有效解决沥青夹带沙土和残沙中含油的问题。     

影响煤焦油沥青质测定量的工艺参数

煤焦油通过溶剂分析可定量分离为三部分：甲苯不溶物、沥青质和油相。本文主要研究了煤焦油在此分离过程中芳烃溶剂类型、萃取方法、甲苯溶液浓缩量、烷烃溶剂类型和正庚烷溶剂与甲苯溶液浓缩量的添加比例对煤焦油沥青质沉淀量的影响。结果表明,甲苯溶液浓缩量、正庚烷与甲苯溶液浓缩量的添加比例对沥青质沉淀量的影响较大,萃取方法次之,将苯替换成甲苯影响最小。当选择甲苯溶解煤焦油,超声萃取3h,甲苯溶液浓缩量9mL,正庚烷与甲苯溶液浓缩液的添加比例为20∶1时,煤焦油沥青质的沉淀量为13.4%。本实验表明煤焦油的分离工艺会影响沥青质沉淀量,故在研究煤焦油沥青质性质和结构时需注明沥青质的沉淀分离条件。     

溶剂萃取法分离油砂

溶剂萃取技术是一种很有发展前景的油砂分离方法,具有操作节水节能、适用性广、分离效率高、无乳化现象、溶剂可循环利用、污染小等优点。本研究细致的考察了溶剂种类、溶剂用量、溶剂极性、操作条件(如温度、搅拌强度及时间等)对油砂沥青萃取率的影响,并通过正交实验获得了最佳萃取条件。在此基础上,对萃取组分和残留物质进行族组分分析,发现沥青中的沥青质的溶解性对温度的敏感性大于其余3种组分(饱和分、芳香分和胶质)。同时,通过实验还观察到萃取过程中悬浮于溶液中的沥青颗粒主要以沥青质组分为主,并含有一定量的轻组分;而油砂中的黏土等细颗粒固体(<44μm)则与悬浮沥青颗粒共存于溶液中,有必要采取过滤、离心等手段对萃取液进行处理,以防这些颗粒对后续的炼油过程产生危害。根据前述的实验研究结果,提出了油砂溶剂萃取过程的机理模型。     

溶液接枝合成EPDM-g-SAN体系溶剂回收中组分的气相色谱分析

以甲苯/正庚烷为溶剂,用溶液聚合法合成三元乙丙橡胶(EPDM)-苯乙烯(St)-丙烯腈(An)接枝共聚物(EPDM-g-SAN).采用萃取的方式分离回收溶液接枝合成ENDM-g-SAN体系中的溶剂,利用气相色谱法定量分析分离出的溶液的微量组分,为确定反应体系溶剂回收工艺流程的工业化路线提供依据.     

DCH-18-C-6/乙酸乙酯萃取体系萃取分离铀(Ⅵ)的研究

以二苯并-18-冠醚-6(DCH-18-C-6)作为萃取剂,采用溶剂萃取法萃取分离溶液中的铀(Ⅵ),研究了稀释剂、盐析剂、介质酸度等条件对萃取率的影响,确定了乙酸乙酯为稀释剂,0.1 mol/L的KH2PO4为盐析剂、水杨酸为酸性介质的溶剂萃取体系。该萃取体系在选定的条件下,对1×10-4mol/L的铀酰离子一次萃取率可达82.5%。     

C_12-2-C_12·2Br反胶团萃取胰蛋白酶的研究

研究了C12-2-C12·2Br/正庚烷/正己醇溶液所形成的反胶团体系对胰蛋白酶的萃取,重点考察了离子强度、水相pH值、表面活性剂浓度、正己醇含量等因素对萃取率的影响。结果表明,最佳萃取条件为:KCl浓度为0.1mol/L,水相p H为12,C12-2-C12·2Br浓度为8mmol/L,正己醇与正庚烷的体积比为0.21。胰蛋白酶的萃取率可达81%。     

溶剂萃取1,2-环己二醇的研究

采用萃取平衡实验法,首次研究了用有机溶剂萃取水相中1,2-环己二醇的萃取热力学性质,为1,2-环己二醇的分离、提纯建立了一种新方法并提供了基础数据。考察了乙酸乙酯和乙酸丁酯作为萃取剂,苯、甲苯、环己烷、正庚烷、甲基丙基酮、1,2-二氯乙烷作为稀释剂时,对萃取水相中1,2-环己二醇的影响,并证实了该萃取过程为吸热过程。     

不同有机溶剂对新疆油砂沥青的组成性质影响

油砂作为一种非常规石油资源,越来越受到人们的重视。油砂沥青的含量和性质对其开发有着重要的影响。有机溶剂抽提可以测定油砂沥青的含量。本文研究了3种溶剂对新疆油砂的抽提能力,并对不同溶剂抽提得到的新疆油砂沥青进行了性质分析。结果表明,新疆油砂含油率（甲苯测）为11.75%,属于中品位油砂矿;甲苯、氯仿和石油醚3种不同溶剂对新疆油砂沥青进行抽提,发现3种溶剂抽提能力的大小关系为氯仿＞甲苯＞石油醚;抽提过程中,氯仿表现出对胶质和沥青质较强的萃取能力,而石油醚对沥青质的萃取能力几乎为0,采用氯仿可以更准确地测定油砂沥青的含量。氯仿抽提得到新疆油砂沥青及其组分的杂原子含量和分子量高于甲苯和石油醚抽提的。由红外谱图发现,氯仿抽提得到的油砂沥青的含氧、含硫官能团的吸收峰强度大于甲苯和石油醚抽提的,表明氯仿对油砂沥青中极性物质的抽提能力更强。     

Water‐Based Bitumen Recovery from Diluent‐Conditioned Oil Sands

Important process development aspects leading to more efficient bitumen recovery from diluent‐conditioned oil sands by water‐based methods are discussed. Bitumen viscosity of 0.5–2 Pa·s is required at the processing temperature and can be reduced to this level by bitumen dilution with an organic solvent. Oil sand porosity, however, poses a restriction on the amount of diluent that can be accepted by the oil sand. Also oil sand‐diluent conditioning time is an important process parameter and can vary from a few minutes for oil sands with low‐viscosity bitumen to several hours if viscosity of the bitumen is high. Additionally, the bitumen separation efficiency during digestion and flotation can be enhanced by reducing the bitumen/water interfacial tension through addition, for example, of tripolyphosphate to the aqueous phase.     

Capillary Curves for Ex‐situ Washing of Oil‐Coated Particles

The oil removal efficiency for the ex situ extraction of bitumen from oil sands, or ex situ washing of oil‐contaminated sand and related processes is determined by the balance of forces at the oil/water and solid/fluid interfaces. The objective of this work is to estimate the balance of forces at the interface using dimensionless numbers, and their use in evaluating and engineering ex situ soil washing processes. To this end, bitumen was removed from bitumen‐coated sand particles using a two‐step process. In the first step, the particles were mixed with a suitable solvent (toluene) used, primarily, to reduce the viscosity of bitumen. The particles were then mixed with water or an aqueous surfactant solution capable of producing low interfacial tensions with the solvent‐bitumen mixture. The fraction of oil retained after washing was evaluated as a function of interfacial tension, solvent/bitumen ratio, mixing time, mixing velocity, and particle size. These ex situ washing conditions were normalized using dimensionless film and particle‐based Weber and Capillary numbers. The fraction of oil retained by the particles was plotted against these dimensionless numbers to generate capillary curves similar to those used in enhanced oil recovery. These curves reveal the existence of a critical film‐based Weber number and a particle‐based Capillary number that can be used in the design or evaluation of soil washing processes. The film‐based Weber number also explained literature data that associates interfacial tension with the removal of oil from oil‐based drill cuttings, as well as field observations on the role that particle size plays on the removal of oil in soil washing operations.     

溶剂抽提法分离印尼油砂的实验研究

利用溶剂抽提法对印尼油砂进行萃取分离实验,综合考察了剂砂比、抽提温度、抽提时间、抽提次数等操作条件对油砂沥青提取的影响,确定较佳的油砂分离条件。结果表明,印尼油砂更适合采用溶剂抽提法分离,从油砂沥青提取率、操作成本和环保多角度考虑,在超声波的作用下,剂砂比为2．5,抽提温度40℃,抽提时间30min,抽提3次的条件下,油砂沥青的提取率较高,达到20．31％。     

Clay minerals in nonaqueous extraction of bitumen from Alberta oil sands: Part 1. Nonaqueous extraction procedure

A non-aqueous bitumen extraction process was studied where only toluene and heptane, with no water additions, were used to extract bitumen from two Alberta oil sands ore samples. One sample had a high bitumen (13.5 wt.%) and low fines (5.3 wt.% < 45 μm) contents, while the other sample had an intermediate bitumen (10.5 wt.%) and high fines (23.3 wt.%) contents. Bitumen recovery and product quality were measured under different process conditions such as the ratio of toluene to heptane and settling time. The Dean Stark procedure was used to determine the solids, bitumen and water contents of the extraction products. In addition, the water content was determined by the Karl Fischer titration method. High bitumen recovery was obtained for both oil sands ore samples although the high fines ore sample was more sensitive to the extraction conditions, especially the toluene to heptane ratio. A product with high purity, containing more than 99.5 wt.% bitumen on a solvent-free basis, was produced at room temperature under the optimum extraction conditions tested. The optimum settling time to achieve a pure product was less than 10 min, based on solids and water contents in the supernatant.     

Solvent screening for non‐aqueous extraction of Alberta oil sands

Non‐aqueous extraction of bitumen from oil sands has the potential to reduce fresh water demand of the extraction process and eliminate tailings ponds. In this study, different light hydrocarbon solvents, including aromatics, cycloalkanes, biologically derived solvents and mixtures of solvents were compared for extraction of bitumen from Alberta oil sands at room temperature and ambient pressure. The solvents are compared based on bitumen recovery, the amount of residual solvent in the extracted oil sands tailings and the content of fine solids in the extracted bitumen. The extraction experiments were carried out in a multistage process with agitation in rotary mixers and vibration sieving. The oil sands tailings were dried under ambient conditions, and their residual solvent contents were measured by a purge and trap system followed by gas chromatography. The elemental compositions of the extraction tailings were measured to calculate bitumen recovery. Supernatants from the extraction tests were centrifuged to separate and measure the contents of fine solid particles. Except for limonene and isoprene, the tested solvents showed good bitumen recoveries of around 95%. The solvent drying rates and residual solvent contents in the extracted oil sands tailings correlated to solvent vapour pressure. The contents of fine solids in the extracted bitumen (supernatant) were below 2.9% for all solvents except n‐heptane‐rich ones. Based on these findings, cyclohexane is the best candidate solvent for bitumen extraction, with 94.4% bitumen recovery, 5 mg of residual solvent per kilogram of extraction tailings and 1.4 wt% fine solids in the recovered bitumen. © 2012 Canadian Society for Chemical Engineering     

Parameters and mechanisms in the solvent extraction of mined athabasca oil sand

The efficiency of solvent extraction of bitumen from mined Athabasca oil sands has been studied in laboratory-scale, batch, stirred vessels. Solvent type, solids concentration, stirrer speed and contact time have been identified as important parameters. A theoretical analysis of the extraction process provides a basis by which the various parameters are assessed in terms of relative overall mass transfer coefficients. However, because the size distribution of the oil sand aggregates is difficult to reproduce, the analysis is limited. Greater reproducibility, and similar quantitative results were obtained for the dissolution of pure bitumen from the bottom of the stirred vessels. It is shown that highly aromatic solvents such as benzene and toluene can dissolve bitumen 3–5 times faster than an essentially alpha tic solvent such as kerosene. There is evidence, however, which indicates that solvent properties other than aromaticity are also important. The data indicate that a minimum stirrer speed must be exceeded before the extraction of oil sand or pure bitumen will proceed at a reasonable rate. Above this minimum rate, the mass transfer coefficient increases linearly with stirrer speed. The solids concentration is also important since the data suggest that a higher efficiency is obtained at higher solids concentrations in the range of solid loadings studied.