CO_2刺激响应型清洁压裂液的室内研究

合成正辛酸酰胺丙基叔胺(DOAPTA)与阴离子表面活性剂油酸钠(NaOA)复配,得到一种能够对CO_2刺激响应的清洁压裂液。当DOAPTA-NaOA以物质的量比为0.8∶1配制成总浓度为100mmol/L的溶液,在CO_2作用下,黏度上升最高达2.92Pa·s。流变性测试表明:体系具有黏弹性流体行为;之后滴加NaOH溶液,体系即可转变至最初的低黏状态,实现彻底破胶。该体系增黏和破胶均容易进行,悬砂能力较强(1.64~1.8cm/h),耐温性能好(60℃),有望用于油田压裂作业中。     

CO_2响应性清洁压裂液的研究与评价

制备了CO_2响应性的黏弹性表面活性剂TAV作为清洁压裂液的稠化剂,筛选了反离子盐,得到了压裂液体系的最佳配方,测定了TAV溶液接触CO_2质子化前后的油水界面张力,考察了压裂液的流变性、携砂性、破胶与循环性能及其对岩心伤害情况。实验结果表明,CO_2响应后的TAV溶液可大幅降低油水界面张力,2.5%(w)的TAV溶液在0.2%(w)KCl助剂下,溶液黏度可达78 mPa·s,在110℃下流变剪切120 min黏度满足要求,体系对20～100目范围内的石英砂具有很好的悬浮性,120 min后仍处于均匀分布的状态;电导率测试证实该体系可重复CO_2/N_2响应,在40℃时通N_2后8 min即可破胶,且对岩心伤害最低达到12.7%。     

纳米TiO2改性MES黏弹性胶束溶液的性能

 以可生物降解表面活性剂脂肪酸甲酯磺酸盐(MES)为原料,借助纳米TiO₂与MES胶束的拟交联作用改善MES黏弹性胶束溶液的耐温性与降滤失性,并采用流变测试方法优化了纳米TiO₂改性MES黏弹性胶束溶液各组分的质量分数,考察了纳米TiO₂对MES黏弹性胶束溶液热稳定性、降滤失性、悬砂性、破胶性能以及岩心渗透率的影响,分析了纳米TiO₂对MES黏弹性胶束溶液耐温性与降滤失性的影响机制。结果表明,纳米TiO2改性MES黏弹性胶束溶液的热稳定性明显增强,在70℃、170s?1条件下,其表观黏度达50mPa?s;支撑剂沉降速率明显降低,幅度达30%以上;通过纳米TiO2对MES胶束的拟交联作用,较大幅度地提高了MES胶束溶液的高温降滤失性能,且不影响MES清洁压裂液的破胶性能;纳米TiO₂改性MES黏弹性胶束溶液的破胶滤液对地层伤害小,岩心渗透率恢复率约为85%。     

可重复利用NaOA/Na_3PO_4黏弹性胶束压裂液微观结构与流变特性研究

采用电解质Na3PO4溶液诱导阴离子表面活性剂油酸钠(Na OA)形成蠕虫状胶束体系。利用冷冻断裂蚀刻透射电子显微镜技术(FF-TEM)和流变学方法,研究了Na3PO4在不同质量分数条件下诱导Na OA形成胶束体系的微观结构、流变特性、破胶行为以及重复利用等性能。通过对体系动态模量、剪切黏度、复合黏度等物理量的测量分析,发现该胶束体系在较宽的频率范围内呈现蠕虫状网状结构和优良的黏弹性能。通过内相破胶剂研究了该体系的破胶行为,并结合流变特性测试,证实了该胶束体系具有重复利用的可行性。与目前已成熟应用的羟丙基瓜胶(HPG)压裂液冻胶及其破胶液微观FF-TEM对比分析显示,Na OA/Na3PO4黏弹性胶束体系具有清晰的网状结构,在温和条件下能够实现和HPG经强氧化破胶后相当的破胶效果。上述结果表明Na OA/Na3PO4黏弹性胶束体系能够作为可重复利用清洁压裂液体系,应用前景广阔。     

合成聚合物XJJ- 4 耐高温压裂液室内研究

采用自制聚合物配制出了合成聚合物基高温压裂液研究了体系组成对压裂液性能的影响,考察了组成为:0.40%稠化剂XJJ-4+0.25%交联剂J-1+0.015%pH调节剂W-1+0.2%助排剂。压裂液体系的耐温抗剪切性、黏弹性、流变性以及破胶性。研究结果表明,该压裂液体系在150℃、170 s~(-1)下连续剪切2h后的黏度约120mPa·s,耐温抗剪切性良好;在线性黏弹区内,体系储能模量G′恒大于损耗模量G″,是典型的黏弹性结构流体;稠度系数(2.141 mPa·S~(0.476))较大,流变行为指数(0.476)较小,具有明显的非牛顿流体行为;加入0.01%破胶剂APS,在150℃下3 h完全破胶水化,破胶液黏度1.38mPa·s,残渣含量15 mg/L,且破胶液具有较低的表面张力(26.24mN/m)和界面张力(1.83mN/m),有利于压裂施工后破胶液顺利返排,降低对地层的伤害。     

超分子聚合物清洁CO2泡沫压裂液的研究及应用

采用几种聚合单体、引入特殊官能团合成了一种聚合物,与相关添加剂和CO_2配套使用,形成一种抗高温的超分子聚合物清洁CO_2泡沫压裂液(BCF压裂液)。采用泡沫压裂液性能评价方法对体系进行了室内评价:体系抗温能力可达140℃,具有泡沫质量高、泡沫稳定性强、耐温耐剪切性能好,携砂性能优良等特点,并且压裂液破胶彻底、表面张力低(24 mN/m以下)、残渣含量极低(小于1mg/L)。该体系不仅解决了常规压裂液残渣含量高的问题,也克服了VES清洁压裂液与CO_2配伍性差、耐温耐剪切差等缺点,在延长油田页岩气井中成功实施并取得了良好的增产效果,对低渗、低压、易水锁、强水敏等特殊油气藏的高效开发和储层保护具有重大意义。     

MEA-PEHA复合溶液吸收/解吸CO2气体实验研究

为了开发性能优良的MEA/烯胺复配吸收剂,本研究采用自主设计的CO_2捕集吸收/解吸装置,通过测试烯胺及MEA/烯胺复配吸收剂的吸收速率、吸收量、解吸速率、解吸率等指标确定最佳单组分烯胺溶剂及其与MEA的最佳复配溶剂。研究结果表明,单溶剂中五乙烯六胺(PEHA)的吸收和解吸效果最好,解吸温度最低,是最佳的单组分烯胺吸收剂;不同物质的量浓度比(4∶6~9∶1)的MEA-PEHA复配溶液中,物质的量浓度配比为5∶5的MEA-PEHA复配溶液饱和吸收量最大(1.72mol),平均吸收速率最高(81.74×10~(-6) mol/s),解吸温度最低(68℃),平均解吸速率最大(137.09×10~(-6) mol/s)以及解吸率较高(95.23%),是CO_2捕集的最佳MEA-PEHA混胺体系。     

黏弹性表面活性剂CTAB在钻井液中的应用

实验研究了阳离子型黏弹性表面活性剂十六烷基三甲基溴化铵(CTAB)溶液的流变性、抗温性、降滤失性及配套破胶剂的破胶性能。实验结果表明:将2%CTAB与3%助剂水杨酸钠NaSal混合的基液在剪切速率170s-1、温度25℃、pH=7的情况下混合均匀后能迅速增黏至160 mPa·s;加入少量复合降滤失剂LA(水解聚丙烯腈铵(NH4-HPAN)和磺化酚醛树脂(SMP-Ⅱ)混合而成的复合体系)可显著降低其常温常压滤失量;高效破胶剂Br的破胶性能良好,破胶液的黏度降至1~3 mPa·s。同时室内研究了以阳离子型黏弹性表活性剂CTAB为主剂的钻井液体系——表面活性剂胶束钻井液DIF-a:1.5%CTAB+2.0%NaSal+1.2%复合降黏剂LA+0.5%黄胞胶XC,结果表明:在钻探碳酸盐岩地层时钻井液体系DIF-a产生的流动摩阻小、降滤失性能较好,且钻完井后利于返排,储层渗透率保留率可以达到91.41%,大大降低外部流体对储层造成的损害。     

液态 CO2增稠压裂液流变性能分析

针对目前CO_2干法压裂工艺技术存在压裂液黏度低、携砂困难等技术难题,将氟醚羧酸盐类表面活性剂增稠剂(FAL-16)和络合金属离子(铝)有机盐增稠助剂(FAL-31)分别按1%加量加入液态CO_2中制备了液态CO_2增稠压裂液,采用高压管路流变实验模拟了液态CO_2增稠压裂液在管路内的增稠过程,研究了液态CO_2增稠压裂液的流变性能。研究结果表明:在液态CO_2中加入1%的增稠剂FAL-16和1%增稠助剂FAL-31能显著提高液态CO_2压裂液的黏度,液态CO_2增稠压裂液的黏度最高可以达到20 m Pa·s(压力20 MPa、温度0℃、剪切速率393 s-1),增黏倍数在90数498之间,液态CO_2增稠压裂液呈现剪切稀化特性,黏度随着温度的增加呈指数递减;随温度的升高,液态CO_2增稠压裂液体系的流动指数n增大,稠度系数k减小。     

油酸酰胺丙基二甲基叔胺改性黄原胶溶液的流变特性

为改善黄原胶的流变性能,以油酸酰胺丙基二甲基叔胺与环氧氯丙烷为主要原料合成了长链疏水阳离子醚化试剂,并以此阳离子醚化试剂对黄原胶(XG)进行改性制得了长链疏水两性黄原胶(OD-XG)。研究并比较了OD-XG和XG溶液的流变特性,包括稳态黏度、流动曲线、触变性及黏弹性,并进一步研究了其耐温耐剪切性和破胶性能。研究结果表明,OD-XG溶液的黏度较XG显著增加,质量分数为0.6%的OD-XG溶液的黏度(237.97 mPa·s)比XG溶液黏度(74.12 m Pa·s)增大了221%;XG和OD-XG溶液的流动曲线可用非线性共转Jefferys本构方程描述;OD-XG溶液的黏弹性及触变性较XG溶液均显著提高;OD-XG溶液的耐温性能提高,80℃恒温剪切90 min后,质量分数0.4%的OD-XG溶液的保留黏度(70.10 mPa·s)约为XG溶液保留黏度(35.14 mPa·s)的2倍。破胶过程流变性研究结果表明,加入破胶剂过硫酸铵后OD-XG溶液的破胶情况良好。     

H6P2W18O62/MCM-48催化剂的制备、表征及催化绿色合成己二酸

以MCM-48为载体,通过浸渍法制备了H6P2W18O62/MCM-48催化剂,并采用FT-IR、XRD、SEM、EDS对催化剂进行表征。以微波促进30%(质量分数)H2O2氧化环己酮合成己二酸反应为探针,考察了H6P2W18O62/MCM-48的催化性能,并通过正交实验确定了优化的工艺条件。结果表明,采用H6P2W18O62负载量40%的H6P2W18O62/MCM-48催化剂,在优化的合成己二酸的工艺条件下,即催化剂质量分数(以环己酮质量计)5.1%、n(C6H10O)∶n(H2O2)∶n(H2C2O4.2H2O)=100∶450∶1.88、反应温度95℃、微波功率300 W、反应时间3.5h,己二酸收率可达81.3%;催化剂重复使用5次,己二酸收率仍可达到64.6%。     

Nanocatalysts: Effect of Active-phase and Promoter on Catalytic Properties and Performance in the Hydrodesulfurization Reaction

The influence of various amounts of phosphorus addition on performance of NiMoP/Al₂O₃ and CoMoP/Al₂O₃ nanocatalysts was examined in hydrodesulfurization of thiophene. The nanocatalysts were synthesized via sonochemical technique. The prepared samples were characterized by XRD, FESEM, BET, and FTIR analysis. The catalytic activity in hydrodesulfurization reaction was investigated in a batch stirred slurry reactor at 160°C and atmospheric pressure. The characterizations confirmed highly dispersion of active phase and formation of amorphous AlPO₄ species on the support surface. The results obtained from thiophene hydrodesulfurization showed the nanocatalysts contained 1 wt% of phosphorus had the highest activity. The CoMoP/Al₂O₃ and NiMoP/Al₂O₃ nanocatalysts with optimum phosphorus loading nearly gave 100% conversion of thiophene, so that the sulfur compound concentration in final solution was less than 50 ppm.     

Petroleum Hydrocarbons Extraction Efficiency of Carbon Tetrachloride and Trichlorotrifluoroethane: A Comparative Study

Abstract

Petroleum hydrocarbons (PHC) contaminated water samples, prepared in laboratory, were analyzed using infrared spectroscopy to compare PHC extraction efficiency of carbon tetrachloride (CCl₄) and trichlorotrifluoroethane (C₂Cl₃F₃) solvents. The comparison of the results illustrated that PHC extraction efficiency of CCl₄ was greater than C₂Cl₃F₃. The higher extraction efficiency of CCl₄ was ascribed to its more non-polar nature and higher polarity index. This study supported the selection and use of CCl₄ for extraction and quantification of PHC of groundwater samples of the projects carried out in the department.     

Nanosized Platinum-Loaded H-ZSM-5 Zeolite Catalysts for n-Hexane Hydroconversion

Abstract

A series of nanosized platinum-containing catalysts was successfully loaded on/in zeolite H-ZSM-5 via exchanging the zeolitic proton with platinum from Pt tetramine dichloride complex. Another series of Pt/H-ZSM-5 catalysts was prepared via wet impregnation of H₂PtCl₆ solution for comparison. The latter series was found to produce lower Pt dispersion. Pt dispersion was determined by H₂ chemisorption. Catalyst characterization via ammonia temperature-programmed desorption (TPD), temperature-programmed reduction (TPR), and transmission electron microscopy (TEM) was examined for all catalysts and showed large differences in particle sizes. The data on n-hexane reactions of the catalysts of both series confirmed the formation of Pt nanoparticles in the exchanged catalysts. The relatively lower density and strength of acid sites acquired by Pt-exchanged catalysts contributed to this difference; stronger acid sites in the impregnated catalysts are in favor of hydrocracking reactions, which inhibit isomerization selectivity.     

Characterization of Al2O3–ZrO2 Mixed Oxide Supported Mo Hydrotreating Catalyst

Abstract

A series of molybdenum catalysts supported on Al₂O₃–ZrO₂ mixed oxide containing 50% ZrO₂ and 50% Al₂O₃ were prepared by incipient wetness technique and characterized by BET surface area, X-ray diffraction, temperature programmed reduction and oxygen chemisorption. The catalytic activities for hydrodesulphurization (HDS), hydrogenation (HYD), and hydrocracking (HYC) were determined using thiophene, cyclohexene, and cumene as model compounds, respectively. Results indicate that up to 8 wt% Mo loading, the catalyst is well dispersed and crystallite growth occurred beyond this loading. Also both oxygen uptake and catalytic activities increase with Mo loading up to 8 wt% and then decreases at higher loading. A linear correlation was obtained between oxygen uptake and all catalytic activities and the correlation coefficients obtained suggest that the order of catalytic activities for HDS, HYD, and HYC is: HDS > HYD > HYC. Furthermore, the catalytic activities of the mixed oxide supported catalyst for HDS, HYD, and HYC were higher than those supported on pure alumina and pure zirconia. The incorporation of 3% Co on 8% Mo catalyst was determined to result in enhanced activity for HDS, HYD, and HYC.     

Production of olefins from syngas over Al2O3 supported Ni and Cu nano-catalysts

The most important products that can be produced from syngas are methanol, dimethyl ether and light olefins (ethylene and propylene). The light olefins are the most important syngas products, because many of the chemicals are produced from them. The aim of this work was to study the olefins production from syngas over Al₂O₃-supported Ni-Cu nano-catalysts. In addition, the effect of various factors such as catalyst on olefin production and CO conversion has been investigated. The concentration of heavier olefins (C5) was greater than the remaining olefins, since the rate of reactions must be increased to form C1 to C4. In the case of a Ni/Al₂O₃ catalyst, C1 and C4 was initially increased and then decreased with an increase in Ni loading from 0% to 15%.     

复合SiO2-WO3催化剂的制备、表征及氧化脱除苯并噻吩性能

 采用溶胶-凝胶法制备了SiO₂-WO₃催化剂,并采用XRD、FT-IR、BET、TG-DTA等方法对催化剂进行表征。以苯并噻吩(BT)为模型化合物,H₂O₂为氧化剂,考察了催化剂的活性元素、制备方法、n(W)/n(Si)和焙烧温度对其催化氧化脱硫活性的影响。结果表明,W的引入降低了SiO₂的比表面积,SiO₂-WO₃催化剂中W的主物相为WO₃。在以W为活性组元,且n(W)/n(Si)为0.1时,500℃焙烧得到的SiO₂-0.1WO₃催化剂具有最好的催化脱硫活性。在模拟油20 mL、催化剂SiO₂-0.1WO₃用量0.04 g、n(H₂O₂)/n(S)为15.9、乙腈/模拟油体积比0.3、65℃反应60 min的条件下,苯并噻吩模拟油脱硫率可达99.3%。     

氧化镁改性微米TS-1催化丙烯环氧化

合成了粒径在1~2 μm的廉价微米TS-1,并经MgO改性,杀灭其上少量的酸中心;采用SEM、XRD、BET对MgO改性前后的TS-1进行了表征,并考察了其在甲醇溶剂体系丙烯环氧化的催化性能。结果表明,TS-1催化剂经MgO改性后,可以显著提高其催化丙烯环氧化反应的环氧丙烷(PO)选择性,减少副反应的发生;在最优化反应条件CH₂O₂ =1.0 mol/L, θ = 60℃, t = 60 min, p_C3↓H6↓ = 0.6 MPa,以及按每1 gTS-1需80 mL CH₃OH的比例下,H₂O₂转化率达到99.5%,环氧丙烷选择性达到96.7%,环氧丙烷收率比未改性的微米TS-1也有明显提高。     

Design of Catalyst Support for Deep Hydrodesulfurization of Gas Oil

Abstract

Alumina-silica (Al₂O₃-SiO₂) composite supports were examined to find the optimum state of support (i.e., composition and morphology). SiO₂ content in the Al₂O₃-SiO₂ support induced a shift of the main peak to higher frequency ascribed to an increased amount of Mo₈O₂₆ ^4?. A 75 wt% Al₂O₃-25 wt% SiO₂ support had homogeneously dispersed alumina particles of smaller size with high crystallinity. Hydrodesulfurization (HDS) of straight-run gas oil and its conventionally hydrotreated straight-run gas oil was performed over NiMo sulfides supported on Al₂O₃-SiO₂ composites. The high crystallinity of NMASA2-27 may be related to the high HDS and hydrogenation activity of NiMo sulfides due to its moderate interaction with the alumina surface.     

Application of Light Hydrocarbon (C7+) and Biomarker Analyses in Characterizing Oil from Wells in the North and North Central Sinai,Egypt

Abstract

Seven representative oil show samples from wells in the north and north central Sinai have been characterized by means of a variety of organic geochemical techniques (C₇ hydrocarbon and biomarker analyses), to illustrate origin, differences, and similarity among oils. These oils were obtained from Cretaceous and Jurassic reservoirs. The C₇ oil correlation star diagram (OCSD) suggests closely related oils, derived mainly from similar source rocks, while the C₇ oil transformation star diagram (OTSD) and C₇ light hydrocarbon analyses indicate a minor degree of transformation of some oils, as Misri-1, Halal-1, and Nakhl-1 oils were subjected to evaporative fractionation. Moreover, the studied oils show no sign of water washing and biodegradation. Molecular characteristics suggest pre-Tertiary shales and carbonate source rocks, deposited under a saline oxic environment, rich in terrigeneous organic sources with significant bacterial and algal input. Since the studied oils are of mixed marine and terrestrial origin, C₇ signature of these oils is not representative of their origin and should be supported by other geochemical evidence (e.g., biomarkers) to predict their origin.