甲醇柴油微乳液制备及稳定性的实验研究

复配油酸,二乙醇胺,span80,op-4四种表面活性剂,将其加入到加甲醇柴油混合体系中,制备甲醇柴油微乳液,并采用正交试验方法与粘度指数法,考察了制备温度,搅拌时间,搅拌速度,助表面活性剂用量,甲醇含量5种因素对甲醇柴油微乳液稳定性的影响程度。实验结果表明,当m(油酸)/m(二乙醇胺)/m(span80)/m(OP-4)=10∶2∶3∶2时,可增溶甲醇量最大,正交试验结果表明:样品粘度指数最小,50℃恒温前后的粘度变化最小,为稳定性最佳的甲醇柴油微乳液配方,显著性检验结果表明影响因素作用程度依次为:甲醇含量制备温度搅拌时间助剂用量搅拌速度。在试验温度为30℃,搅拌时间为12 min,搅拌速度为300 r/min时,添加甲醇质量分数为5%的实验条件下制备甲醇柴油微乳液。     

甲醇混合燃料稳定性的研究

为了找到能够代替石油的其它燃料,利用非离子型表面活性剂复配制备甲醇混合燃料,并以燃料油、甲醇、表面活性剂＋助表面活性剂为三组分做出相图。通过微乳液相区面积考察不同因素对制备甲醇混合燃料的影响。因素包括不同表面活性剂的复配,甲醇加入量、不同助表面活性剂以及助表面活性剂的用量。结果表明最佳的实验条件为：表面活性剂复配比为4：1,助剂为正丁醇和油酸,甲醇与燃料油的理想配比为8：1。并对实验结果进行了分析。     

柴油微乳液研制及影响因素的考察

利用非离子型表面活性剂复配制备W/O柴油微乳液,并以油、水、表面活性剂 助表面活性剂为三组分做出相图。通过微乳液相区面积考察不同因素对制备柴油微乳液的影响。因素包括不同表面活性剂的复配,不同的助表面活性剂及助表面活性剂与表面活性剂的比(m(C)∶m(T))。并用不同浓度的碱液代替水相,考察碱液对柴油微乳液形成的影响。结果表明最佳实验条件为:表面活性剂复配比为0.667,m(C)∶m(T)=0.3,助剂为正丁醇,碱液质量分数为0.1%。利用HLB值理论和界面膜理论对实验结果进行了分析。     

基于油茶籽油为油相的烟酰胺微乳制备及性能

以油茶籽油为油相、烟酰胺溶液为水相,制备油茶籽油-烟酰胺微乳。利用伪三元相图法和马尔文激光粒度仪研究微乳液的相行为、粒径,测定微乳液的防晒能力和体外抗氧化能力。结果显示：微乳液的最佳配方为复配表面活性剂司盘80与吐温80质量比为4∶1,聚乙二醇-400为助表面活性剂,复配表面活性剂与助表面活性剂质量比为1∶1,油茶籽油与混合表面活性剂质量比为6∶4。制备的油茶籽油-烟酰胺微乳中,烟酰胺溶液占微乳液总质量的8.34%。微乳液粒径为80 nm左右。在290～400 nm的紫外吸收峰数量多于油茶籽油,证明其防紫外线能力强于油茶籽油。微乳液对DPPH·、·OH、ABTS~+、O₂~-·均有抑制能力,表现出良好的抗氧化性能。为后续防晒制剂的开发提供理论依据。     

基于伪三元相图的壬二酸微乳液的制备与评价

制备稳定的壬二酸祛痘微乳。方法：借助伪三元相图,通过不同表面活性剂的复配筛选壬二酸微乳区,并进行处方筛选及工艺优化。选取3种壬二酸微乳体系进行粒径、理化性质、稳定性及试用评价。结果：筛选出3种壬二酸微乳的粒径分别为（1247.6±13.29） nm、（381.85±0.92） nm、（520.8±16.97）nm,经过稳定性测试表明制备的壬二酸微乳均一稳定,粒径及PDI差异无统计学意义。试用人群77%反馈有祛痘效果,基本无刺激性。结论：本研究通过筛选出壬二酸微乳液区域并成功制备了6%壬二酸微乳液,开发并优化了微乳纳米体系,可作为壬二酸的载体,提高其治疗效果。     

甜橙微乳化香精制备研究

采用微乳化技术制备了透明的甜橙微乳化香精。对不同表面活性剂的复配在微乳化香精中的应用效果进行了研究,考察了不同助表面活性剂对透明微乳化香精的影响,确定了该微乳体系所能增溶的香精含量,并对制备的透明微乳化香精进行了稳定性考察。结果表明当采用吐温-80与十聚甘油单油酸酯、蔗糖酯-11为复配表面活性剂,丙二醇为助表面活性剂,香基质量分数为24％时能够制备透明、稳定的微乳化香精,其平均粒径为14．6 nm,加入水中时具有很高的透明度,适用于透明饮料的加香应用。所制备的透明微乳化香精具有良好的低温、高温稳定性,该甜橙微乳化香精生产设备投资小、工艺简单,便于扩大化生产。     

超声波及乳化剂复配对制备微乳柴油的影响

采用超声波处理为分散手段,阳离子表面活性剂十六烷基三甲基溴化铵为主要乳化剂,正丁醇为助剂,制备微乳柴油。优化了超声波作用参数:最佳频率40 kHz,最佳声强0.266 W.cm-2,最佳超声作用时间20 min。研究了复配乳化剂对制备微乳柴油的影响,选择非离子型表面活性剂Span80、Span60,阴离子表面活性剂十二烷基苯磺酸钠与十六烷基三甲基溴化铵复配制备微乳柴油,其中Span80效果最佳,并且处理相同量的微乳柴油,助剂醇的用量降低为原来的1/6。微乳化柴油稳定性良好,至今已放置14个月不分层。     

乳化剂对丙烯酸酯微乳液聚合的影响

考察了4种不同类型乳化剂及其复配使用对丙烯酸酯三元微乳液聚合的影响,结果表明:反应型乳化剂TS-02与阴离子乳化剂SDS复配为制备聚丙烯酸酯微乳液的较佳乳化体系。乳化剂用量由1%增加到4%,乳胶粒径由208nm降至26nm;微乳液黏度随之升高,凝聚率降低。乳化剂用量过低,则微乳液稳定性降低,转变为水凝胶时间缩短。     

复配非离子生物柴油纳米乳的制备工艺

选用复配壬基酚聚氧乙烯醚非离子表面活性剂作为生物柴油的乳化剂,考察了2种壬基酚聚氧乙烯醚m（NP-6）∶m（NP-10）、复配表面活性剂HLB值、m（油）∶m（表面活性剂）、水滴加速率以及搅拌速度等因素对纳米乳液乳化性能的影响。通过实验确定了制取纳米乳液的最佳工艺条件：m（NP-6）∶m（NP-10）=6∶4,复配表面活性剂HLB值为11.88,m（油）∶m（表面活性剂）=1.6～1.8,水滴加速率在0.7mL/min以下,以及搅拌速度为700～800r/min时,在25℃下用乳化反转点法制得稳定的水包油纳米乳,此条件下纳米乳颗粒形貌为球形,粒径分布主要在20～30nm。     

微乳化柴油制备工艺研究

本文介绍了微乳柴油的组成,确定了柴油、水、表面活性剂、助表面活性剂的质量配比对微乳柴油的最大溶水量的影响。研究结果表明：表面活性剂油酸：氨水比例为1：1．8、助表面活性剂正丁醇所占体积的5％、聚合氯化铝用量为0．7％时,其溶水量为最大,制得微乳柴油稳定时间在一个月以上,其粘度符合燃油国家标准。     

Effect of Branched Alcohols on Phase Behavior and Physicochemical Properties of Winsor IV Microemulsions

The microemulsion phase behavior and physicochemical properties of surfactant–water–alcohol–oil systems are the pioneer laboratory study as a function of alcohol, water content and temperature to develop an experimental investigation for a better understanding of the microstructure of a single phase microemulsion and its stability under reservoir condition during hydraulic fracturing to recover the residual trapped oil. Viscosified surfactants are used as an efficient proppant conducting medium in hydraulic fracturing applications. The physicochemical properties of microemulsions are very helpful for characterization of microemulsions to justify their abilities and screening of surfactants. In the study, two branched alcohols, 2-methyl butan-2-ol, 3-methyl butan-1-ol selected as the cosurfactant in the proposed microemulsion system and their effect in tailoring the viscosity of microemulsions were studied. Microemulsion regions elucidated from Winsor’s pseudophase model of an oleate surfactant show a signatory distribution pattern of components between different domains with non-polar and asymmetric geometry of cosurfactant directs macromolecular alignments; their alignment contributes to a viscous microemulsions (gel) regime. The effect of surfactant and alkali, and the experimental temperature on the rheological properties of the lamellar mesophase were investigated. Phase transit regions and exact microemulsion and viscous microemulsion magnitudes were elucidated with the help of conductivity and viscosity studies of the ternary system as a function of the aqueous fraction and were in good agreement with Winsor’s pseudophase model. Dynamic and steady shear rheological studies showed that the gel is viscoelastic in nature, sustain viscosity and elastic modulus values appropriate for proppant suspension under high shear conditions. The proppant suspension and thermal behavior of ideal gel composition was found to be suitable for Coal Bed Methane and soft rock, clay reservoir stimulation.     

Preparation of Pt–Ru–Co trimetallic nanoparticles and their electrocatalytic properties

Ternary Pt–Ru–Co nanoparticles are prepared by microemulsions procession. These resulting materials showed a homogenous alloy structure, the mono-dispersion and an average diameter of 2.7 ± 0.6 nm with a narrow particle size distribution. The composition of Pt–Ru–Co nanoparticles can be controlled by adjusting the initial metal salt solution and preparation conditions. Pt–Ru–Co ternary metallic nanoparticles can enhance catalytic activity towards methanol oxidation compared to Pt–Ru bimetallic nanoparticles.     

Microemulsion polymerization of siloxane with nonionic surfactants as emulsifiers

Polysiloxane nanolatices were prepared by the microemulsion polymerization of octamethylcyclotetrasiloxane (D₄) with nonionic polyoxyethylene alkyl ether and polyoxyethylene aryl ether as surfactants, ethylene glycol or aminoethanol as a cosurfactant, and potassium hydroxide or dipotassium dimethylsilanolate (I) as an initiator. The effect of the different initiators and the amount of cosurfactant on the microemulsion polymerization rate of D₄ was investigated. The initiator, potassium hydroxide, had a similar catalytic activity to I, and adding the cosurfactant changed a common siloxane emulsion to a microemulsion. At a same reaction conditions, the polymerization rate of D₄ with aminoethanol as a cosurfactant was much faster than that of ethylene glycol. The kinetics of this siloxane microemulsion polymerization was consistent with Morgen‐Kaler theory. The transparency value of the resultant polysiloxane nanolatex was more than 95% when the amount of ethylene glycol was more than 25% and the siloxane amount was about 30 wt % of the reaction mixture. A nanolatex of polydimethylsiloxane‐co‐polyvinylmethylsiloxane, which was crosslinked with potassium persulfate, revealed that the mean diameter of the droplets was 32 nm with a narrow distribution. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 3587–3593, 2003     

Optimization of Parameters for Synthesis of MFI Nanoparticles by Taguchi Robust Design

MFI‐type zeolite was successfully synthesized by hydrothermal crystallization of clear synthesis mixtures. A statistical experimental design method (the Taguchi method with an L8 orthogonal array) was implemented to optimize the experimental conditions for the preparation of MFI nanocrystals with respect to particle size and distribution as the desirable properties. In the Taguchi experimental design, crystallization temperature, water content, template/silica molar ratio, aluminum content, as well as the presence of alkaline cations were chosen as significant parameters affecting the properties. It was shown that water and aluminum content of the synthesis solution were the most important parameters affecting particle size and distribution. The MFI nanocrystals with an average particle size of 95 nm and the narrow particle size distribution of ± 8.5 nm were synthesized under optimum conditions.     

沉淀反应工艺条件的变化对纳米二氧化硅宏观粒径的影响

文章采用化学沉淀法,以蛇纹石酸浸滤饼碱浸所制备的硅酸钠溶液为原料、硫酸为沉淀剂,以所制得二氧化硅样品的宏观粒径为主要考察指标,通过单因素条件实验和正交实验,分别考察了表面活性剂用量等因素的变化对所制备的纳米二氧化硅样品宏观平均粒径的影响,所确定的优化工艺条件下的重复实验结果表明:所制备的二氧化硅样品的微观粒径约为25nm,宏观平均粒径均小于1.30μm。     

球形木质素珠体的制备及其粒径分布研究

利用反相悬浮聚合技术制备球形木质素珠体,并采用正交实验综合研究了木质素珠体研制过程中各影响因素对珠体形成和粒径分布的影响。结果表明,以自制的复合分散剂L1, 采用体积比为1∶1的变压器油与氯苯混合物作为分散相,油水相比为3∶1,搅拌速度为200 r/min,反应温度80℃左右,反应体系的酸度控制在1.5 mol/L时,反应2 h后所得到的球形木质素珠体粒径分布最均匀,粒径在0.4~0.8 mm的木质素珠体占木质素珠体总质量的83.2%。     

复合诱变抗性筛选法选育高转化甘油产1，3-二羟基丙酮菌株

在测定不动杆菌（Acinetobactersp．）Aspl6菌株链霉素最低杀菌浓度的基础上,对菌株进行UV和Co诱变处理后,利用链霉素抗性平板筛选获得l株遗传性能稳定、高转化甘油产1,3-二羟基丙酮的突变株Asrl68,将突变株在5．0g·L-1酵母膏、140．0g·L-1甘油、7．0g·L-1。CaC03组成的发酵培养基中于30℃、250r·minll摇床培养50h,1,3-二羟基丙酮的产量达到136g·L-1,比出发菌株提高200％。表明通过UV和”Co诱变,结合链霉素抗性平板筛选,可大幅提高不动杆菌转化甘油产1,3-二羟基丙酮的能力。     

Preparation and characterisation of BaTiO3 nanopowder by microwave assisted microemulsion method

Through the microwave assisted reverse microemulsion method, BaTiO₃ nanopowders are prepared in 10 min by selecting water/OP-10/hexanol/cyclohexane reverse microemulsion system, Ba(NO₃)₂ and tetrabutyl titanate as reactants. The effect of reaction temperature, reaction time, concentration of reactants and molar ratio of water and surfactant on the reaction was studied, and the prepared powders were characterised by X-ray diffraction, TEM and X-ray fluorescence analysis. The results show that cubic phase BaTiO₃ powders of particle size about 50–80 nm with uniform distribution and good dispersion were prepared under atmospheric pressure in 10 min at 65°C. The method has characteristics of lower reaction temperature, shorter reaction time, smaller particle size, narrow particle size distribution and good particle dispersion.