十八烷基己基甲基羧基甜菜碱的合成及性能

以硬脂酸和己酸为原料合成了不对称双长链烷基羧基甜菜碱——十八烷基己基甲基羧基甜菜碱(C18+6B),测定了C18+6B的表面活性,并与总碳原子数相等的对称型双十二烷基甲基羧基甜菜碱(di C12B)进行比较,以了解表面活性剂分子结构对性能的影响。结果表明,C18+6B的表面活性与di C12B基本相当,但水溶性远好于di C12B。作为无碱驱油用表面活性剂,C18+6B对大庆原油来说HLB值略偏高,45℃下单独使用能将大庆原油/地层水界面张力降至10-2m N/m数量级,在大庆油砂上的饱和吸附量比di C12B低30%。C18+6B单独能将C7~C9正构烷烃/大庆地层水界面张力降至10-3m N/m数量级,而通过与亲油性更强的di C12B以及亲水性甜菜碱复配后,能将大庆原油/地层水界面张力降至10-3m N/m数量级,并能显著改善配方的水溶性。     

双十二醇聚氧乙烯醚甲基羧基甜菜碱的合成及性能

双十二烷基甲基甜菜碱(diC 12B)是一种优良的无碱驱油用表面活性剂,但由于亲油性太强,在水中的溶解性较差,并且在油砂表面具有较大的吸附量。本文试图在diC 12B分子中引入EO基团,以改善其性能。为此以溴代十二烷和三缩四乙二醇为原料合成了单分布的十二醇聚氧乙烯(4)醚,再经氯代并与一甲胺和氯乙酸锂反应,最终合成了双十二醇聚氧乙烯(4)醚甲基羧基甜菜碱(diC 12EO4B)。产物经核磁和质谱表征,证明与目标产物的分子结构相符。与diC 12B相比,diC 12EO4B在水中的溶解度显著增加,25℃时达到1.5×10-4mol/L,是diC 12B的3倍左右,45℃下在石英砂/水界面的饱和吸附量是diC 12B的70%左右。diC 12EO4B保留了diC 12B的高表面活性,如较低的临界胶束浓度,1.6×10-5mol/L;较高的降低表面张力的效能,γcmc=29.3 mN/m;在空气/水界面具有较大的饱和吸附量,6.5×10-10mol/cm2;和较小的分子截面积,0.26 nm2。diC 12EO4B具有优良的降低油/水界面张力的能力,45℃下单独能将大庆地层水/C7~9正构烷烃界面张力降至10-3mN/m数量级,将大庆原油/地层水的界面张力降至10-2mN/m数量级。通过与亲油性表面活性剂diC 12B以及C16B复配,能在0.062 5~5 mmol/L总浓度范围内将大庆原油/地层水的界面张力降至10-3mN/m数量级,无需加入任何碱或电解质。     

1,3-双癸基甘油醚乙氧基化物的合成与性能研究

以癸醇、环氧氯丙烷以及环氧乙烷为原料,合成了双烷基型非离子表面活性剂1,3-双癸基甘油醚乙氧基化物(diC10GE-EOn)。中间产物1,3-双癸基甘油醚(diC10GE)经红外、核磁和质谱检验证明为目标化合物。diC10GE-EOn(n=6.5～12.5)具有优良的表面活性,25℃下cmc为7.50×10-7～1.24×10-6mol·L-1,在空气/水界面上的饱和吸附量大于1.0×10-9mol.cm-2,分子截面积小于0.16 nm2。diC10GE-EO6.5具有良好的亲油性,通过与羧基甜菜碱类两性表面活性剂复配,其中diC10GE-EO6.5的摩尔分数为0.4,在总表面活性剂质量分数为0.05%～0.50%时可使大庆四厂原油/地层水平衡界面张力降到10-3mN.m-1数量级,无需添加任何碱、中性电解质或助表面活性剂。     

双十二烷基甲基羧基甜菜碱在水溶液中的胶束化研究

采用表面张力法和荧光探针法研究了25℃下双十二烷基甲基羧基甜菜碱(diC12B)在水溶液中的临界胶束浓度(cmc)和胶束聚集数(Nm)。结果表明,用2种方法测得的cmc值基本一致,分别为3.7×10-6和3.5×10-6mol.L-1;与十八烷基二甲基羧基甜菜碱(cmc为4.2×10-6mol.L-1)相比,diC12B具有更强的亲油性,但cmc值相当,表明双长链烷基在一定程度上具有抑制胶束形成的作用。由于具有双长链烷基,diC12B的水溶性较差,其单一体系的Nm不便测定,通过将其与同类物质十二烷基二甲基羧基甜菜碱混合,可以测得混合胶束的Nm随体相中diC12B摩尔分数的变化,外推得到单一diC12B的Nm=65,这一Nm值明显大于具有类似结构的阳离子表面活性剂双十二烷基二甲基溴化铵的Nm=29,表明diC12B分子在胶束中的排列比阳离子表面活性剂更为紧密,这一特征与其在水/空气界面的单分子层中紧密排列、具有较小的分子截面积相符合。     

重烷基苯磺酸盐驱油剂中试产品的应用性能

在1000t/a降膜式连续磺化装置上对重烷基苯的磺化进行了中试放大,结果表明中试产品质量可靠。经复配的驱油剂中试产品能在较宽的表面活性剂浓度和碱浓度范围内与大庆原油、辽河原油及苏北原油形成超低界面张力,尤其能溶于总矿化度12×104mg/L、钙镁离子质量浓度为5000mg/L～6000mg/L的中原油田地层水中,在无碱条件下使中原油田原油/地层水的界面张力降至10-2mN/m～10-3mN/m数量级。对大庆原油和苏北原油的驱油试验表明,中试驱油剂ASP(碱-表面活性剂-聚合物)体系的驱油效率比水驱提高15%～35%OOIP(原油地层储量)。     

双-十二醇聚氧乙烯醚甲基羧基甜菜碱的合成及性能

双十二烷基甲基甜菜碱(diC₁₂B)是一种优良的无碱驱油用表面活性剂,但由于亲油性太强,在水中的溶解性较差,并且在油砂表面具有较大的吸附量。本文试图在diC₁₂B分子中引入EO基团,以改善其性能。为此以溴代十二烷和三缩四乙二醇为原料合成了单分布的十二醇聚氧乙烯(4)醚,再经氯代并与一甲胺和氯乙酸锂反应,最终合成了双十二醇聚氧乙烯(4)醚甲基羧基甜菜碱(diC₁₂EO₄B)。产物经核磁和质谱表征,证明与目标产物的分子结构相符。与diC₁₂B相比,diC₁₂EO₄B在水中的溶解度显著增加,25℃时达到1.5×10^-4mol/L,是diC₁₂B 的3倍左右,45℃下在石英砂/水界面的饱和吸附量是diC₁₂B的70%左右。diC₁₂EO₄B保留了diC₁₂B的高表面活性,如较低的临界胶束浓度,1.6×10^-5mol/L;较高的降低表面张力的效能,g_cmc=29.3mN/m;在空气/水界面具有较大的饱和吸附量,6.5×10^-10mol/cm²;和较小的分子截面积,0.26nm²。diC₁₂EO₄B具有优良的降低油/水界面张力的能力,45℃下单独能将大庆地层水/C₇~C₉正构烷烃界面张力降至10^-3mN/m数量级,将大庆原油/地层水的界面张力降至10^-2mN/m数量级。通过与亲油性表面活性剂diC₁₂B以及C₁₆B复配,能在0.0625~5mmol/L总浓度范围内将大庆原油/地层水的界面张力降至10^-3mN/m数量级,无需加入任何碱或电解质。     

C16格尔伯特醇聚氧烷烯醚硫酸盐的制备及其界面性能研究

用C₁₆格尔伯特醇经共聚加成环氧丙烷(PO)和环氧乙烷(EO),再经氨基磺酸硫酸化合成了一种支链烷基醇醚硫酸盐(C₁₆GA-PES)。这种新型阴-非复合型表面活性剂具有优良的水溶性、耐盐性和表面活性。45℃下溶于大庆地层水,单独即可将大庆轻质原油/地层水界面张力降至超低;对稍重质的大庆三类油层油,使用该表面活性剂与少量亲油性更强的表面活性剂混合,亦可将界面张力降至超低。这种新型结构表面活性剂吸附在油/水界面形成的单分子层具有从强亲油到弱亲油-弱亲水再到强亲水的过渡结构,而双烷基链又赋予单分子层较高的烷基链密度,从而增强了单分子层与油分子的相互作用,易于将原油/水界面张力降至超低。与相应的嵌段中间体相比,共聚所得非离子中间体黏度显著降低,便于管道输送并且有利于采用SO₃气体降膜式硫酸化工艺制备硫酸盐。     

驱油用芥酸酰胺丙基甜菜碱的合成与性能评价

以芥酸、N,N-二甲基-1,3-丙二胺与氯乙酸钠为原料,经过酰胺化、季铵化两步反应,合成了芥酸酰胺丙基羧基甜菜碱EBC。使用FTIR、MS对酰胺中间体EA和甜菜碱产物EBC的结构进行了表征。评价了甜菜碱EBC的表界面性能、吸附特性和增黏性。结果表明,该表面活性剂的临界胶束浓度(CMC)为1.02×10-5mol/L,对应的表面张力γCMC为29.60 mN/m;最小烷烃碳数(nmin)为16;无碱条件下,EBC与大庆和苏丹油田原油达到10-4~10-3mN/m数量级的超低界面张力,m(EBC)∶m(DABS)=8∶2,复配体系质量分数0.001%~0.20%与长庆马岭油田原油达到超低界面张力,界面性能优异,且抗稀释能力强;该表面活性剂在天然油砂上的吸附量为0.07~0.51 mg/g砂,小于1.0 mg/g砂的指标要求;而且具有明显的增黏性能。甜菜碱EBC可作为较理想的驱油用表面活性剂应用于化学复合驱。     

耐温抗盐表面活性剂溶液与原油的界面张力

研究了二甘醇双(α-磺酸钠)烷基羧酸酯(DMES-n)、十二烷基二甲基胺乙内酯(BS-12)两类表面活性剂与原油的界面张力,并考察了表面活性剂的耐温抗盐性。实验结果表明,DMES-n能将油水界面张力降低至10-2mN/m数量级,但是抗盐性不如BS-12;将两者复配后,在NaCl浓度为30 000～100 000 mg/L、MgCl2和CaCl2浓度为10 000 mg/L的条件下,DMES-14/BS-12和DMES-16/BS-12复配体系都能将油水界面张力降低至10-3mN/m数量级,表明复配体系既具有更好的降低界面张力的能力,同时还具有良好的抗高盐、高钙镁性能以及良好的耐温性。     

超低界面张力石油磺酸盐复配驱油剂研究

通过室内实验研究了溶液质量分数、矿化度对石油磺酸盐溶液与大庆L区块原油的界面张力的影响,并将不同类型表面活性剂分别与石油磺酸盐复配,筛选出能够使油/水界面张力降至超低(10-3 mN/m数量级)的最优增效组合,以取代ASP复合驱中所加的碱.实验结果表明,在矿化度为6 000～10 000 mg/L,钙、镁离子质量浓度不超过20 mg/L时,石油磺酸盐表面活性剂有良好的抗盐性,可使油/水界面张力达到超低.在实验所选的不同类型表面活性剂中,石油磺酸盐与甜菜碱型表面活性剂复配起到明显的增效作用,特别是与椰油酰丙基磺基甜菜碱复配增效作用尤为显著,且两者复配的浓度范围较宽,油/水界面张力易达到超低.     

Synthesis of Didodecylmethylcarboxyl Betaine and Its Application in Surfactant–Polymer Flooding

Enhanced crude oil recovery by chemical flooding has been a main measure for postponing the overall decline of crude oil output in China, and surfactant-polymer (SP) flooding may replace alkali-surfactant-polymer flooding in the future for avoiding the undesired effects of using alkali. In this paper the synthesis of a surfactant with a large hydrophobe, didodecylmethylcarboxyl betaine (diC₁₂B), and its adaptability in SP flooding were investigated. The results show that diC₁₂B can be synthesized by reaction of didodecylmethyl amine, a product commercially available, with chloroacetic acid in the presence of NaOH, with a resulting yield as high as 80?wt% under appropriate conditions. With double dodecyl chain diC₁₂B is highly surface active as displayed by its low CMC, 3.7?×?10^?6?mol?L^?1, low ??_CMC, 27?mNm^?1, as well as high adsorption and small cross section area (??0.25?nm²) at both air/water and oil/water interfaces at 25?°C. By mixing with conventional hydrophilic surfactants diC₁₂B can be well dissolved in Daqing connate water and reduce the Daqing crude oil/connate water interfacial tension to about 10^?3?mN?m^?1 at 45?°C in a wide total surfactant concentration range, from 0.01 to 0.5 wt%. And a tertiary oil recovery, 18?±?1.5?% OOIP, can been achieved by SP flooding using natural cores without adding any alkaline agent or neutral electrolyte. DiC₁₂B seems thus to be a good surfactant for enhanced oil recovery by SP flooding.     

Effects of Polyether Surfactants on Dynamic Interfacial Tension of Betaine Solutions against Crude Oil

The dynamic interfacial tension (IFT) of betaine and betaine/polyether‐nonionic surfactant‐mixed systems against hydrocarbons, kerosene, and crude oil–water was studied using a spinning‐drop tensiometer. The influence of average molecular weight of polyether‐nonionic surfactants on IFT of mixed solutions was investigated. On the basis of the experimental results, one can find that it is difficult to reach the ultralow IFT value for betaine solution against hydrocarbon and kerosene because of the mismatch between the hydrophobic and hydrophilic groups. After purification, kerosene still contains a small amount of carboxyl groups, which can exert a synergistic effect on surfactants resulting in a lower IFT. The IFT of betaine and mixtures against Daqing crude oil can reach an ultralow value because of the mixed adsorption of surfactant and petroleum soap molecules. For mixed solutions, with the increasing concentration of added polyether, the decrease of petroleum soaps at the oil–water interface results in the destruction of synergistic effects.     

A New Series of Double-Chain Single-Head Sulfobetaine Surfactants Derived from 1,3-Dialkyl Glyceryl Ether for Reducing Crude Oil/Water Interfacial Tension

A new series of sulfobetaine surfactants with double-chain single-head structure were derived from 1,3-dialkyl glyceryl ethers and their performances in reducing Daqing crude oil/connate water interfacial tension (IFT) in the absence of alkali were studied. With a large hydrophilic head group and double hydrophobic chains, these surfactants are efficient at reducing crude oil/connate water IFT. Those with didecyl and dioctyl are good hydrophobic surfactants that can reduce Daqing crude oil/connate water to ultra-low IFT by mixing with a small molar fraction of various conventional single-chain hydrophilic surfactants, such as α-olefin sulfonates, dodecyl polyoxyethylene (10) ether, and cetyl dimethyl hydroxypropyl sulfobetaine. The asymmetric double-chain sulfobetaine derived from 1-decyl-3-hexyl glyceryl ether can reduce Daqing crude oil/connate water IFT to ultra-low solely over a wide concentration range (0.03–10 mM or 0.0017–0.58 wt.%), which allows for use of an individual surfactant instead of mixed surfactants to avoid chromatographic separation in the reservoir. In addition, formulations rich in sulfobetaine surfactants show low adsorption on sandstone, keeping the negatively charged solid surface water-wet, and forming crude oil-in-water emulsions. These new sulfobetaine surfactants are, therefore, good candidates for surfactant-polymer flooding free of alkali.     

A New Type of Sulfobetaine Surfactant with Double Alkyl Polyoxyethylene Ether Chains for Enhanced Oil Recovery

A new type of sulfobetaine with double alkyl polyoxyethylene (n) ether chains, dicoconut oil alcohol polyoxethylene (n) ether methylhydroxylpropyl sulfobetaine (diC_12–14E _n HSB) was synthesized using a commercial nonionic surfactant, coconut oil alcohol polyoxethylene (n) ether, as raw material and its properties as a surfactant for enhanced oil recovery (EOR) in the absence of alkali was studied. The purified product is a mixture of homologues with mainly C₁₂/C₁₂, C₁₂/C₁₄ and C₁₄/C₁₄ alkyl chains and widely distributed EO chains (n = 2.2 on average) with an average molar mass of 742.6 g/mol. The diC_12–14E_2.2HSB has an improved aqueous solubility at 25 °C compared with didodecylmethylhydroxylpropyl sulfobetaine (diC₁₂HSB), a homologue without an EO chain, and is highly surface active as reflected by its low CMC (4.6 × 10^?6 mol/L), high saturated adsorption (6.8 × 10^?10 mol/cm²) and small cross sectional area (0.24 nm²/molec.) at the air/water interface. With a hydrophile–lipophile balance well matched with Daqing crude oil/connate water system, the sulfobetaine can reduce Daqing crude oil/connate water interfacial tension to ultra-low values at 45 °C in the absence of alkali, and displays a low saturated adsorption at the sandstone/water interface (0.0024 mmol/g), reduced by 69 and 92 % respectively in comparison with that of the corresponding carboxyl betaine, diC_12–14E_2.2B and its homologue without an EO chain, didodecylmethylcarboxyl betaine (diC₁₂B). With these excellent properties diC_12–14E_2.2HSB gives a high tertiary recovery, 18.4 % original oil in place, when mixed with other hydrophobic and hydrophilic sulfobetaines in surfactant-polymer (SP) flooding free of alkali. The insertion of EO chains in combination with the replacement of carboxyl betaine by sulfobetaine is therefore very efficient for improving the properties of the double chain hydrophobic carboxyl betaines as surfactants for SP flooding free of alkali.     

岔30断块S/P二元复合驱实验研究

针对华北岔30断块90℃高温、地层水矿化度18765.1 mg/L的特点,筛选得到了石油磺酸盐CDS-1与疏水缔合聚合物HNT201-3二元复合体系。0.05%CDS-1/HNT201-3二元复合体系与原油的界面张力可降到10^-2mN/m数量级;当HNT201-3浓度为1250mg/L时,复合体系的表观粘度为23.7 mPa.s。非均质岩心（模拟油层非均质变异系数和平均空气渗透率）驱油试验结果表明,注入驱油体系0.3PV、后续保护段塞0.1PV（聚合物HNT201-3浓度1250mg/L）时,可比水驱提高采收率19.73%OOIP。     

高30断块表面活性剂体系筛选

华北油田高30断块油藏目前已进入高含水开发后期,含水率97.0%,标定采收率仅为29.4%。当前,可大幅度提高油层波及体积和驱油效率的复合驱,是提高油藏最终采收率的有效途径和方法。已有研究表明,动态界面张力达到1-0 2mN/m数量级的复合体系的驱油效果与1-0 3mN/m数量级平衡界面张力的复合体系的驱油效果基本相当。实验表明,随着表面活性剂浓度的增加,表面活性剂/原油的界面张力逐渐降低,当界面张力达到最低值后又逐渐升高并达到平衡状态。筛选出了适合于高30断块的表面活性剂体系-0.05%石油磺酸盐CDS-1体系,该体系与原油的瞬时动态界面张力和平衡界面张力达到可以大幅度降低残余油饱和度的1-0 2~1-0 3mN/m数量级。     

Novel surfactants for ultralow interfacial tension in a wide range of surfactant concentration and temperature

This work investigates the possibility of injecting dilute aqueous solutions of novel surfactants into the Yibal field (Sultanate of Oman). This was accomplished through an experimental protocol based on the following criteria: (i) compatibility of the surfactants with the high-saline reservoir water (∼200 g/L); (ii) low interfacial tension (IFT) between crude oil and reservoir water (less than 10⁻² mN m⁻¹); and (iii) maintaining the low IFT behaviour during the entire surfactant flooding. Novel surfactants selected in this study consist of a series of ether sulfonates (AES-205, AES-128, AES-506, and 7–58) and an amphoteric surfactant (6–105). These surfactants were found to be compatible with reservoir water up to 0.1% surfactant concentration, whereas 6–105 and 7–58 showed compatibility within the full range of surfactant concentration investigated (0.001–0.5%). All surfactant systems displayed dynamic IFT behavior, in which ultralow transient minima were observed in the range 10⁻⁴–10⁻³ mN m⁻¹, followed by an increase in the IFT to equilibrium values in the range 10⁻³–10⁻¹ mN m⁻¹. The results also showed that with respect to concentration (0.05–0.5%) and temperature (45–80°C), AES-205 and 7–58 surfactants exhibit a wide range of applicability, with the IFT remaining below 10⁻² mN m⁻¹, as required for substantial residual oil recovery. In addition, ultralow IFT were obtained at surfactant concentrations as low as 0.001%, making the use of these surfactants in enhanced oil recovery extremely cost-effective.     

Novel fluorinated surfactants for enhanced oil recovery in carbonate reservoirs

Novel surfactant‐polymer (SP) formulations containing fluorinated amphoteric surfactant (surfactant‐A) and fluorinated anionic surfactant (surfactant‐B) with partially hydrolyzed polyacrylamide (HPAM) were evaluated for enhanced oil recovery applications in carbonate reservoirs. Thermal stability, rheological properties, interfacial tension, and adsorption on the mineral surface were measured. The effects of the surfactant type, surfactant concentration, temperature, and salinity on the rheological properties of the SP systems were examined. Both surfactants were found to be thermally stable at a high temperature (90 °C). Surfactant‐B decreased the viscosity and the storage modulus of the HPAM. Surfactant‐A had no influence on the rheological properties of the HPAM. Surfactant‐A showed complete solubility and thermal stability in seawater at 90 °C. Only surfactant‐A was used in adsorption, interfacial tension, and core flooding experiments, since surfactant‐B was not completely soluble in seawater and therefore was limited to deionized water. A decrease in oil/water interfacial tension (IFT) of almost one order of magnitude was observed when adding surfactant‐A. However, betaine‐based co‐surfactant reduced the IFT to 10^?3 mN/m. An adsorption isotherm showed that the maximum adsorption of surfactant‐A was 1 mg per g of rock. Core flooding experiments showed 42 % additional oil recovery using 2.5 g/L (2500 ppm) HPAM and 0.001 g/g (0.1 mass%) amphoteric surfactant at 90 °C.