胜利油田胜坨原油乳化特性研究

研究了胜利油田胜坨原油以及从中分离出的沥青、胶质和烷烃的乳化特性及其协同效应。结果表明,胜坨原油经稀释后能与酸性水、中性水及碱性水乳化形成超高含水量(>90%)w/o型乳状液。分散在烷烃中的沥青以及水相中存在的高价电解质对乳状液具有重要的稳定作用。在酸性尤其是碱性水中,胶质及沥青中所含的极性组分能与水相中的碱或酸反应生成少量低表面活性的水溶性表面活性剂,但不足以使w/o型乳状液破乳或转为o/w型。胶质与碱水之间的动态最低界面张力可达10~(-2)mN/m,与碱水乳化时,胶质和沥青之间存在最强的协同效应。     

用废弃油脂合成驱油用表面活性剂研究

为开发廉价实用的驱油用表面活性剂,本研究以废弃油脂为原料,采用缩合、稀释磺化等工艺在室内合成了多种可能用于驱油的表面活性剂。用大港孔店原油和地层水对这些表面活性剂进行了性能评价,包括界面张力、乳化性能、抗吸附性能、表面活性剂和聚合物的相互影响。其中,合成的烷醇酰胺类表面活性剂WX20和羧基甜菜碱类表面活性剂ST经过地层砂四级吸附后界面张力仍然能够达到10~(-3)m N·m~(-1)数量级。结果表明:用废弃油脂合成的烷醇酰胺类和羧基甜菜碱类表面活性剂各项指标和常用石油磺酸盐接近,但用量较石油磺酸盐少,综合成本低,有望用于实际驱油;而用废弃油脂合成的乙氧基脂肪酸甲酯类、脂肪酸甲酯磺酸盐表面活性剂均可使孔店油水形成超低界面张力,但综合指标不能达到实际驱油要求。为油田三次采油化学驱开发廉价、高效、实用的表面活性剂提供了技术支撑。     

用废弃油脂合成驱油用表面活性剂

为开发廉价实用的驱油用表面活性剂,本研究以废弃油脂为原料,采用缩合、稀释磺化等工艺在室内合成了多种可能用于驱油的表面活性剂。用大港孔店原油和地层水对这些表面活性剂进行了性能评价,包括界面张力、乳化性能、抗吸附性能、表面活性剂和聚合物的相互影响。其中,合成的烷醇酰胺类表面活性剂WX20和羧基甜菜碱类表面活性剂ST经过地层砂四级吸附后界面张力仍然能够达到10~(-3)m N·m~(-1)数量级。结果表明:用废弃油脂合成的烷醇酰胺类和羧基甜菜碱类表面活性剂各项指标和常用石油磺酸盐接近,但用量较石油磺酸盐少,综合成本低,有望用于实际驱油;而用废弃油脂合成的乙氧基脂肪酸甲酯类、脂肪酸甲酯磺酸盐表面活性剂均可使孔店油水形成超低界面张力,但综合指标不能达到实际驱油要求。为油田三次采油化学驱开发廉价、高效、实用的表面活性剂提供了技术支撑。     

辛癸酸甘油酯和橄榄油的极性调控研究

本文以添加了不同浓度表面活性剂司盘80(Sp80)的辛癸酸甘油酯(Octanoic acid glyceride,ODO)和橄榄油作为模型油脂,测定在不同剪切速率下ODO和橄榄油的表观黏度,分析不同司盘80添加量对ODO和橄榄油界面张力的影响,并对其抗聚并稳定性进行了评价,从而探讨不同浓度表面活性剂下油脂极性的变化规律。结果表明,ODO和橄榄油体系的表观黏度随司盘80添加量的增加而增大;当司盘80浓度小于5%时,ODO-水界面张力降低,ODO极性增大;而在橄榄油体系中,橄榄油-水的界面张力达到平衡所需司盘80用量较ODO少,当司盘80浓度大于1%时,橄榄油极性与界面张力无明显变化,且司盘80可增强ODO和橄榄油油滴的抗聚并稳定性;当司盘80浓度大于5%时,由于油相极性较大,油水间作用力增强且过量胶束生成,反而促进了橄榄油油滴的聚并。     

纺织品加工用的非离子表面活性剂

表面活性剂是那些在低浓度下就能降低水的表面和界面张力的物质。表面活性剂是由一个分子上连接着几种化学基团所组成的,这些化学基团在性质上是不同的,在溶解特性方面也有明显差异。非离子表面活性剂R-O∈CH_2CH_2O）_xH在水中溶解时不会电离,即它们既不带负电行也不带正电行。这类表面活性剂主要是烷氧基化的伯醇、仲醇或烷基酸等化合物。本文主要介绍非离子表面活性剂的应用和临界特性。 临界胶束浓度 在低浓度下,非离子表面活性剂同其它类型的表面活性剂一样,会排列和吸附在水的表面和与容器接触的界面上。一旦表面和界面被表面活性剂饱和时,表面活性剂分子在溶液中会形成聚集体,这些聚集体被称为胶束。在开始形成胶束时的浓度称之为临界     

醇在水-硝基乙烷体系中的界面吸附

:研究了正丁醇、异丁醇、正戊醇在硝基乙烷—水体系中的界面吸附 ,测定了不同实验体系中的界面吸附参数 .结果表明 ,不同体系中界面张力与溶液醇浓度间的关系均遵守Langmuir Szyszkowski方程 ,硝基乙烷的存在改变了醇的界面吸附参数 ,降低了醇的表面活性 .     

NaCl浓度对蔗糖酯黄原胶乳浊液稳定性的影响

研究NaCl浓度对蔗糖酯-黄原胶溶液的水力学直径DH、ζ-电势和界面张力及乳浊液的粒径d4,3、ζ-电势、粘度和稳定性的影响。在此基础上,探讨蔗糖酯-黄原胶相互作用与乳浊液稳定性之间的联系。结果表明:随着NaCl浓度增加,由于静电屏蔽作用,蔗糖酯-黄原胶溶液的DH值、ζ-电势和界面张力均增大,导致乳浊液ζ-电势和d4,3也逐渐增大。NaCl浓度达到0.1mol/L时,由于蔗糖酯-黄原胶疏水作用增强,形成蔗糖酯-黄原胶复合物,提高液滴的空间位阻作用,使得复合乳浊液稳定性高于蔗糖酯乳浊液稳定性。     

影响核桃油包水乳液物理与氧化稳定性的因素分析

以核桃油为油相,以聚甘油聚蓖麻油酸酯(PGPR)为表面活性剂,制备油包水(W/O)乳液,乳液于55 ℃避光保存,每隔1 d测定乳液液滴的平均粒径及粒径分布等物理特性,同时检测乳液初级氧化产物—脂质氢过氧化物与次级氧化产物—己醛,探究水油界面与表明活性剂浓度对W/O乳液稳定性影响。结果表明,在W/O乳液,油水界面存在加速乳液脂质氧化,降低了乳液氧化稳定性。0.3～1.0% PGPR,表面活性剂浓度增大显著降低乳液液滴粒径,提高乳液物理稳定性;同时,表面活性剂浓度增加显著推迟了初级与次级产物形成延迟期,提升了乳液脂质氧化稳定性。W/O体系中过量表面活性剂与脂质氢过氧化物相互作用,增加了脂质氢过氧化物在油相的浓度,并降低了该初级氧化物的分解速率。     

表面活性剂的化学结构和周围解质对其在液/空气界面上的吸附及胶束作用的影响

虽然临界胶束浓度(CMC)常被用来作为表面活性剂的表面活性的量度,但表面活性剂吸附在界面上的趋势、胶束作用以及在液/空气表面上的吸附作用却并不一定是相互平行地发生变化的。在液/空气界面上的     

改性菊糖的表面特性及储藏特性

菊糖与十八烷基异氰酸酯在有机溶剂中发生甲氨酰化反应,生成的氨甲基菊糖具有表面活性。氨甲基菊糖能明显降低界面张力且在电解质介质中有较高的浊点。实验表明,当NaCl浓度达到4mol/L、MgSO4浓度达到1mol/L,温度升至100℃时溶液仍然未混浊。聚乙二醇(PEG)系列表面活性剂在电解质溶液中没有这么高的浊点,从而显示了氨甲基菊糖作为表面活性剂的优越性。通过储藏实验,发现以改性菊糖为表面活性剂的乳液性能稳定。     

丝胶蛋白质溶液的动态表面吸附过程

采用Wilhelmy吊片法测定一定浓度的丝胶溶液在不同pH条件下的动态表面张力,通过数学经验公式分析动态吸附数据,从吸附模型、吸附分子面积和吸附速率等方面,说明丝胶溶液的动态表面吸附有扩散和动力学吸附2个过程。在不同pH条件下,以丝胶溶液的动态表面压p对吸附时间t,动态表面张力tγ对lgt,以及ln(dp/dt)对p作图,根据经验公式推导出丝胶溶液表面张力下降一半时的时间t1/2、丝胶蛋白质分子吸附控制参数n,丝胶分子在界面上初始渗透和固定时所占面积ΔA1、以及在界面上重排和再取向时所占面积ΔA2。结果表明:丝胶蛋白质分子的吸附过程是扩散动态吸附;在表面上吸附的丝胶蛋白质分子的构象转变存在2个动态过程,即在界面上的分子发生初始渗透和固定阶段,以及吸附在表面上的分子发生重排和再取向阶段;丝胶溶液的pH值影响动态表面张力和分子吸附面积;在pH值低于丝胶等电点时,丝胶分子在界面初始吸附和重排面积较小,动态表面张力较高,表面吸附速度较慢,当pH值高于等电点,表面张力变小,吸附速度加快,丝胶在界面吸附的分子面积变大。     

大豆蛋白-溶血磷脂O/W型复合乳液的乳化特性

针对大豆溶血磷脂添加量对大豆分离蛋白-溶血磷脂复合乳化体系乳化特性的影响进行探究。对复合乳化体系分别进行了界面蛋白吸附量、界面张力、乳化活性、乳化稳定性、粒径分布、Zeta电位的测定,并采用光学显微镜对乳液中油滴分布及微观结构变化进行观察。结果表明:随着溶血磷脂添加量的增加,乳化特性指标均基本呈现先升高后降低的趋势。其中,当溶血磷脂添加量为10%时,乳液的乳化特性表现最佳,这表明添加适量溶血磷脂会促进其与大豆分离蛋白的相互作用,降低界面张力,在油-水界面上形成较稳定的界面膜,形成稳定的复合乳状液。     

米糠不溶性膳食纤维的提取及吸附铅离子探究

为促进米糠资源的综合利用,对米糠不溶性膳食纤维的提取方法及吸附Pb2+特性进行研究。采用酶-化学方法提取脱脂米糠中的不溶性膳食纤维。通过单因素和正交试验对高温淀粉酶添加量、NaOH质量分数、碱解时间和碱解温度对产物提取率和纯度的影响进行研究,确定制备米糠不溶性膳食纤维的较优参数条件。结果显示,在高温淀粉酶添加量0.3%,NaOH质量分数3%,75℃碱解75 min时,所得产物纯度85.74%,得率37.40%。吸附试验结果:提取物在20 mg/L Pb2+水溶液中振荡反应180 min时达到吸附平衡,此时吸附率为96.67%。动力学符合准二级动力学方程,能较好地描述米糠不溶性膳食纤维与Cd2+的结合行为,说明吸附过程存在化学吸附。热力学探究表明:25℃有利于吸附的进行,这一过程是熵驱动、自发进行的,同时吸附Pb2+强度较弱,推测作用力主要是物理吸附。米糠不溶性膳食纤维具有较好的吸附Pb2+能力。本试验为米糠膳食纤维材料的提取条件及其吸附Pb2+特性提供了理论依据。     

DISPERSION STATE OF PROTEIN-STABILIZED EMULSIONS

The stability of concentrated benzene-in-water emulsions emulsified by bovine serum albumin (BSA) in the presence of various concentrations of sodium chloride has been measured in the light of the coalescence kinetics. On the acid and alkaline sides of the isoelectric point of BSA (pH 4.9), the rate of coalescence between globules decreased and approached that at the isoelectric point of BSA with increasing concentrations of sodium chloride. In these systems, the interfacial tension at the benzene/aqueous BSA solution interface, and the globule size distribution in the emulsions, reached the values observed at the isoelectric point when the concentration of sodium chloride was above about 50 mM. The role of the adsorbed film of BSA on the surface of dispersed globules is considered in relation to the dissociation state of the BSA molecules.     

Interfacial Tensions of Commercial Vegetable Oils with Water

The pendant drop method, the current method of choice for interfacial tension measurement, was used to obtain the interfacial tensions of a number of vegetable oils with water. Contrary to the reports of earlier workers, all triglycerides examined had similar interfacial tensions with water, all values being in the range 23-26 mNm^?1. Long chain fatty acids, principal contaminants of commercial oils, had little effect on the interfacial tension. When the oils were exposed to alkaline conditions, the mono- and diglycerides formed by hydrolysis caused the interfacial tension to drop rapidly, in agreement with previously reported results for the effect of mono- and diglycerides on interfacial tensions.     

分散染料NaOH介质染色技术

以分散紫900、分散红902、分散蓝825和分散橙BROD四只分散染料为例,比较其耐碱性和耐氧化性,考察以NaOH为介质的一浴一步法和一浴二步法碱性退浆染色短流程工艺.结果表明,该四只染料具有很好的耐碱性和耐氧化剂性,适合以2g/LNaOH为介质的碱性条件染色,且其一浴一步法和一浴二步法碱性退浆染色短流程工艺的效果差别不大,能获得更好的弹性、柔软性和光滑性;采用该短流程碱性工艺加工时,控制不当纤维因过度失重导致断裂强度下降,应合理控制染色时间.     

Interfacial and emulsifying behaviour of crayfish protein isolate

The interfacial behaviour of adsorbed protein films constituted with a crayfish protein derivate that is typically produced as by-product from the food industry, has been studied at the air-water and oil-water interfaces. An analysis of the surface pressure under compression-expansion cycles of this protein was carried out as a function of time, concentration and pH (2 and 8). Besides, interfacial tension and adsorption kinetics also were determined as a function of time at different concentrations and pH values. Interfacial rheological properties were studied under dilatational deformations applied to a single droplet, either at the initial step of film formation or once the interfacial tension was at equilibrium and the film was completely formed. The contribution of the interfacial properties to the behaviour of oil-in-water emulsions stabilised with this protein derivative were also analysed. Finally, droplet size distributions obtained for concentrated emulsions stabilised by crayfish protein were analysed and related to the interfacial tension behaviour. We have demonstrated that crayfish proteins at pH 8 show higher solubility, smaller aggregates and better interfacial activity (higher surface pressure and lower interfacial tension) with higher interfacial viscoelasticity, than at pH 2. A two-dimensional model of the results showed that oil-water and air-water interfaces are clearly related to the improved stability of emulsion made with crayfish proteins at pH 8.     

Improvement of selective removal of heavy metals in cyanobacteria by NaOH treatment

In the freshwater cyanobacterium, Tolypothrix tenuis, treatment with 0.1 M NaOH increased its Cd-selective adsorption ability in the presence of Ca(2+) or Mg(2+). The selective adsorption was also achieved by other alkaline treatments. Energy-distributed spectroscopy analysis revealed that Cd(2+) was found mainly on the surface of non-treated cells, whereas it was distributed throughout the cell after NaOH treatment. The alkaline treatment was effective in increasing the selective adsorption ability of the cyanobacterium for other bivalent heavy metals such as Cu(2+), Pb(2+) and Zn(2+). The treatment was also applicable to Anabaena variabilis and Microcystis aeruginosa, which are typical cyanobacteria causing algal blooms. The main binding site of Cd(2+) in NaOH-treated cells is assumed to be the carboxyl groups because the binding ability of the cells was diminished by the esterification of carboxyl groups. These results suggest that alkaline treatment of cyanobacteria is a useful technique for producing biosorbents having highly specific binding abilities for heavy metals.     

Mobilization of manufactured gas plant tar with alkaline flushing solutions

This experimental study investigates the use of alkaline and alkaline-polymer solutions for the mobilization of former manufactured gas plant (FMGP) tars. Tar-aqueous interfacial tensions (IFTs) and contact angles were measured, and column flushing experiments were conducted. NaOH solutions (0.01-1 wt.%) were found to significantly reduce tar-aqueous IFT. Contact angles indicated a shift to strongly water-wet, then to tar-wet conditions as NaOH concentration increased. Column experiments were conducted with flushing solutions containing 0.2, 0.35, and 0.5% NaOH, both with and without xanthan gum (XG). Between 10 and 44% of the residual tar was removed by solutions containing only NaOH, while solutions containing both NaOH and XG removed 81-93% of the tar with final tar saturations as low as 0.018. The mechanism responsible for the tar removal is likely a combination of reduced IFT, a favorable viscosity ratio, and tar bank formation. Such an approach may have practical applications and would be significantly less expensive than surfactant-based methods.