表面修饰TiO2纳米颗粒在齿轮油中的应用研究

文章介绍了一种表面修饰TiO2纳米颗粒在齿轮油中的应用研究,内容包括其在齿轮油复合剂配方中的极压抗磨性能、减摩性能和适应性考察等,并对纳米添加剂与硫化烯烃之间的复配作用进行了评价。结果表明,所制备的TiO2纳米颗粒在齿轮油中具有良好的减摩抗磨作用和优异的极压性能,在高档齿轮油的研发工作中具有较大的应用价值。     

Si-Sn型复合纳米粒子添加剂的摩擦磨损和自修复性能

采用化学方法制备了Si-Sn型复合纳米添加剂,分别采用四球摩擦磨损试验机和环-块摩擦磨损试验机考察了其作为矿物油添加剂的抗磨减摩性能及对磨损表面的修复作用。 用扫描电子显微镜、粗糙度测定仪以及X射线光电子能谱仪等对摩擦副磨损表面进行分析，并探讨其抗磨减摩作用机理。结果表明，Si-Sn型复合纳米添加剂具有优良的减摩抗磨性能,且对磨损表面具有一定的修复作用。Si-Sn型复合纳米添加剂在摩擦表面沉积并在接触区的高温、高压作用下熔融铺展,形成低剪切强度的表面膜,由于这层膜的剪切强度较低,可以减少摩擦界面的粘着磨损,表现出良好的减摩抗磨和自修复性能。     

Mg-Sn型复合纳米粒子的摩擦学和磨损修复性能

采用化学方法制备了Mg-Sn型复合纳米添加剂,分别采用四球摩擦磨损试验机和环-块摩擦磨损试验机考察了其作为矿物油添加剂的抗磨减摩性能及对磨损表面的修复作用.采用扫描电子显微镜、粗糙度测定仪及X-射线光电子能谱仪等对摩擦副磨损表面进行了分析,并探讨了其抗磨减摩作用机理.结果表明.Mg-Sn型复合纳米添加剂具有优良的减摩抗磨性能,且对磨损表面具有一定的修复作用.其原因在于,Mg-Sn型复合纳米添加剂在摩擦表面沉积,并在接触区的高温高压作用下熔融铺展,形成低剪切强度的表面膜.由于这层膜的剪切强度比较低,可以减少摩擦界面的黏着磨损,故表现出良好的减摩抗磨和自修复性能.     

多功能含硫氮硼酸酯的性能研究

用四球机和HQ—1环块实验机考察了一种含琉代氨基甲酸基团的硼酸酯在液体石蜡中的承载能力、减摩和抗磨性能。井考察了其抗腐蚀性和热稳定性。实验结果表明：该添加剂的承载能力和减摩性能与ZDDP的相当,抗磨性能在低于392N时与ZDDP相当,而载荷高于392N时抗磨性能略优于ZDDP;此外该添加剂还具有良好的抗腐蚀性能和热稳定性。采用X射线光电子能谱仪对摩擦表面进行了分析,并探讨了添加剂的抗磨作用机理。     

纳米SiO_2润滑添加剂的摩擦学性能及其抗磨减摩机理研究

研究了纳米SiO_2作为润滑油添加剂的摩擦学性能及其与MoDDP的协同作用,并通过SEM,EDS,XPS等手段对磨斑表面进行分析,探索了纳米SiO_2的抗磨减摩机理。结果表明,当纳米SiO_2加入量(w)为0.5%时,润滑油的摩擦系数和磨斑直径分别比基础油降低30.6%和35.5%,显著提高了基础油的抗磨减摩性能。纳米SiO_2与MoDDP具有良好的协同作用。纳米SiO_2的抗磨减摩机理为:在摩擦副表面沟槽部位纳米SiO_2和MoDDP膜起填补作用;在凸处,纳米SiO_2起微"滚动轴承"作用,MoDDP在摩擦能量作用下分解为软的MoS_2并沉积在摩擦副表面,以上综合作用减小了摩擦,修复了摩擦副表面,从而提高了润滑油的抗磨减摩性能。但随着时间的延长,SiO_2对MoS_2沉积膜又具有轻微的刮擦作用。     

润滑油用纳米TiO2的表面改性及自修复性能研究

采用油酸对纳米TiO2进行表面改性，使其稳定分散于基础油中。利用HQ-1摩擦磨损试验机考察纳米TiO2的自修复性能，并探讨其自修复机理。试验结果表明，经改性后的纳米TiO2粉体作为润滑添加剂具有良好的分散稳定性、减摩抗磨性和自修复性。     

纳米微胶囊铜的摩擦学性能研究

用化学方法制备了纳米微胶囊铜润滑添加剂,通过四球机考察了其在矿物油中的摩擦学性能,结果表明：纳米微胶囊铜润滑添加剂具有优良的减摩、抗磨和极压性能。其润滑作用机理是Cu纳米粒子在摩擦表面沉积,并在高温高压下形成低剪切强度的表面膜,减少摩擦磨损,表现出良好的极压和抗磨减摩性能。     

水基硼酸盐纳米粒子的摩擦学性能研究

采用沉淀法合成了多种硼酸盐纳米粒子，用透射电镜对其形貌进行了表征，并用四球摩擦试验机考察了其在水介质中的摩擦学性能。结果表明，硼酸盐纳米粒子作为水基添加剂可使水的承载能力显著提高，抗磨减摩性能也有较大提高。随着硼酸盐纳米粒子在水溶液中添加量的增大，最大无卡咬负荷增大；在392 N负荷下，添加量为1.0%或1.5%时，磨斑直径最小；在添加量一定时，摩擦磨损性能与负荷有关，在较小或较大负荷下抗磨性能更好。结合X射线光电子能谱分析可推断添加剂的作用机理是添加剂在摩擦过程中发生了摩擦化学反应，并在摩擦副表面生成了含氧化物的复合润滑膜，有效地提高了水的抗磨减摩性能。     

改性纳米SiO2颗粒的研制及抗磨减摩性能评价

选用纳米SiO2颗粒作为发动机润滑油添加剂,筛选出适宜的溶剂为无水乙醇,最佳改性剂为通过采用不同的溶剂和改性剂,对纳米SiO2颗粒进行表面修饰,制备一系列改性纳米SiO2颗粒,对其进行SEM表征,考察其分散性能和摩擦学性能,筛选出适宜的溶剂及改性剂;并考察改性纳米SiO2颗粒作为润滑油添加剂的摩擦学性能,确定最佳的改性纳米SiO2颗粒添加量。结果表明：对纳米SiO2颗粒进行表面改性的适宜溶剂为无水乙醇,最佳改性剂为KH-550,采用先配制KH-550醇水溶液再加入到反应体系的工艺方式时改性效果更佳;改性纳米SiO2颗粒具有较好的抗磨减摩性能,添加量（w）为2%时抗磨减摩效果较好。     

几种噻二唑二聚体衍生物的摩擦学性能研究

合成了3种噻二唑二聚体衍生物。采用红外光谱仪对其结构进行了表征;用四球摩擦磨损试验机考察了其在蒸馏水中的摩擦学性能;用X射线光电子能谱仪（XPS）分析了磨斑表面典型元素的化学状态。结果表明,添加剂在水中具有优良的承载能力和极压性能,并在一定程度上改善了水的抗磨减摩性能;在摩擦过程中,磨斑表面形成了含氮的吸附膜和含Fe2O3,FeS,FeSO4的化学反应膜,二者协同作用使添加剂在摩擦过程中具有良好的抗磨减摩性能。     

Dibenzothiophene Hydrodesulfurization Activity of MoS2 Supported in Sol–Gel ZrO2–TiO2 Mixed Oxides

Abstract

In this work, we report the effect of support composition on the properties of MoS₂ impregnated in sol–gel ZrO₂–TiO₂ mixed oxides as dibenzothiophene hydrodesulfurization catalyst. The supports calcined at 500°C were characterized by N₂ physisorption and X-ray diffraction (electronic radial distribution function). The oxidic impregnated materials (2.8 Mo atoms/nm²) were sulfided at 400°C under a H₂S/H₂ stream. The sample impregnated on the equimolar support showed the highest activity per mass of catalysts whereas the one with TiO₂ carrier was superior in a per mass of Mo basis. Marked differences in products selectivity were observed by TiO₂ addition in the supports. The hydrodesulfurization route to partially hydrogenated compounds was favored over the mixed oxides-supported catalysts meanwhile the direct desulfurization (to biphenyl) was promoted on the ZrO₂-supported solid. It is suggested that among other properties the dispersion and morphology of the MoS₂ phase could influence that behavior.     

微量TiO2对Ni/SiO2催化剂催化顺酐加氢制γ-丁内酯的促进作用

 采用等体积浸渍法分别制备了Ni/SiO₂和含TiO₂的Ni/SiO₂催化剂,采用XRD、TPR、XPS、N₂吸附-脱附技术对催化剂进行了表征,并将催化剂应用于顺酐液相加氢制γ-丁内酯反应中,考察了Ni含量、TiO₂添加量、催化剂还原温度对催化剂活性的影响。结果表明,Ni/SiO₂催化剂对顺酐液相加氢制γ-丁内酯反应具有很高的催化活性, γ-丁内酯选择性很高;Ni/SiO₂添加微量助剂TiO₂,可以提高该反应的γ-丁内酯选择性。推测可能是由于TiO₂促进了催化剂的还原,产生更多的活性中心,并且在400℃还原时,Ni和TiO₂之间产生了强金属-载体相互作用（SMSI效应）,TiO₂富集到Ni的表面,将电子转移到Ni上,产生了更多有利于吸附羰基的活性中心,从而提高了γ-丁内酯选择性。     

Amorphous TiO2-supported Keggin-type ionic liquid catalyst catalytic oxidation of dibenzothiophene in diesel

Supported ionic liquid(IL) catalysts [C_nmim]_3PMo_(12)O_(40)/Am TiO_2(amorphous TiO_2) were synthesized through a one-step method for extraction coupled catalytic oxidative desulfurization(ECODS) system. Characterizations such as FTIR, DRS,wide-angle XRD, N_2 adsorption–desorption and XPS were applied to analyze the morphology and Keggin structure of the catalysts. In ECODS with hydrogen peroxide as the oxidant, it was found that ILs with longer alkyl chains in the cationic moiety had a better effect on the removal of dibenzothiophene. The desulfurization could reach 100% under optimal conditions, and GC–MS analysis was employed to detect the oxidized product after the reaction. Factors affecting the desulfurization efficiencies were discussed, and a possible mechanism was proposed. In addition, cyclic experiments were also conducted to investigate the recyclability of the supported catalyst. The catalytic activity of [C_(16)mim]_3 PMo_(12)O_(40)/Am TiO_2 only dropped from 100% to 92.9% after ten cycles, demonstrating the good recycling performance of the catalyst and its potential industrial application.     

Hydrogen production by catalytic gasification of petroleum residue

The liquid fuel gasification to obtain a clean flue gas for power generation and produce chemicals such as methanol is a most promising attempt to reduce the greenhouse gas emissions and air pollutants. In this paper, an equilibrium model of liquid fuel gasification was developed by the method of Gibbs free energy minimization. Two kinds of catalysts: Ni/CeO₂/Al₂O₃ and Ni/Al₂O₃ were used to explore the influence of catalysts and operating conditions on hydrogen yield and char conversion. Over the ranges of operating conditions studied, the maximum hydrogen yield reached 52.47 vol%, whereas the char conversion varied between 45.2% and 98.5%. The results indicated that an appropriate reaction temperature is favorable for higher hydrogen production and char conversion. The model was validated with experimental data obtained from a fluidized bed gasifier.     

Fe 3+x-TiO2/Shell光催化剂的制备及其对石油的光催化降解

 以自制的贝壳基规整吸附体为载体,采用浸渍煅烧法制备了Fe ³⁺_x-TiO₂/Shell光催化剂。采用XRD、SEM-EDS和UV-Vis等技术对制备的Fe ³⁺_x-TiO₂/Shell光催化剂进行表征。以石油为降解对象,考察了Fe³⁺掺杂量、Fe ³⁺_x-TiO₂/Shell的负载次数及光照时间对Fe ³⁺_x-TiO₂/Shell光催化活性的影响。结果表明,Fe³⁺掺杂量为0.7%(m(Fe³⁺ )/m(TiO₂)×100%)、Fe ³⁺_0.7-TiO₂负载次数为4次时,制备的Fe ³⁺_0.7-TiO₂/Shell光催化剂的光催化活性最高,300 W碘钨灯照射16 h,石油的光催化降解率达76%。     

微波辐射促进P2O5催化液相贝克曼重排制己内酰胺

 在微波辐射的条件下,以P₂O₅为催化剂,开发了液相贝克曼重排制己内酰胺的新型工艺。研究了加热方式、催化剂（H₃PO₄、ZnCl₂和P₂O₅）、反应容器、微波辐射强度、辐射时间、催化剂用量以及溶剂（环己酮、水和N,N-二甲基甲酰胺）对环己酮肟液相贝克曼重排反应的影响。在催化剂P₂O₅的质量分数为14.0 %（0.19 g）、10 mL N,N-二甲基甲酰胺为反应介质、1.153 g环己酮肟、微波辐射强度为280 W、辐射时间为5.0 min的工艺条件下,环己酮肟的转化率能达到98.69 %,己内酰胺收率达到95.75 %。此外,该工艺操作简单,反应迅速,收率较高,具有潜在的工业化应用前景。     

Understanding wax appearance temperature in light crude oils by DSC,NMR, and HT-GC

The wax precipitated from oil mixtures primarily consists of C18 to C36 (macro crystalline waxes) or C30 to C60 (micro crystalline waxes), both made of aligned paraffinic and naphthenic molecules. Paraffins have significant impact on wax deposition characteristics as paraffin waxes react and respond easily to temperature changes due to its straight chain structure. In this paper, 12 light crudes of different origin were analyzed by DSC. Method was standardized for the determination of WAT in light crudes and these were found to have WAT ranging from 10 to 30°C. Wax content is proportional to enthalpy of crystallization (ΔH) and the ΔH ranges from 3 to 9 J/g. WAT and wax content do not follow the same trend which is understandable as these parameters depends not only on the concentration and molecular weight of the waxes but also on the chemical nature of both waxy and non waxy part of the crude oil. To understand the trend in WAT, these crudes were also analyzed for paraffinic carbon (Cp), Saturates and CH₂/CH₃ ratio by NMR spectroscopy and carbon number distribution by HT-GC. It was observed that WAT correlates fairly well with CH₂/CH₃ ratio which is in an indicator of normal paraffin content as WAT depends primarily on the nature / type of paraffins. The anomalies can be explained through carbon–wise n-paraffin content by HT-GC.     

Synthesis of amphiphilic peroxophosphomolybdates for oxidative desulfurization of fuels in ionic liquids

Three amphiphilic peroxophosphomolybdates [C₄mim]₃PMo₄O₂₄, [C₈mim]₃PMo₄O₂₄ and [C₁₆mim]₃PMo₄O₂₄ were synthesized and characterized. These catalysts were used for extraction and catalytic oxidative desulfurization of fuel with H₂O₂ as an oxidant and ionic liquid [C₄mim]BF₄ as an extractant. It was found that [C₁₆mim]₃PMo₄O₂₄ showed the highest catalytic activity and the sulfur content could decrease to 7.5 ppm. In contrast, the desulfurization system shows very low performance without H₂O₂ or ionic liquid. The detailed reaction conditions were optimized including reaction time, temperature, the dosage of H₂O₂ and catalyst, and different sulfur compounds. After the reaction, the catalysts and the ionic liquid can be cycled 8 times with a little decrease in desulfurization efficiency.     

CO2准干法压裂技术研究及应用

致密砂岩气藏普遍具有储层物性差、孔喉细、黏土矿物含量高的特征,水力压裂易导致储层产生水敏、水锁等液相伤害,影响增产效果。针对此问题,研究了CO₂准干法压裂技术,重点开展了准干法压裂工作液组成、携砂性能、耐温耐剪切性能等方面的研究,形成了一种液态CO₂中含有少量水基压裂液的均匀混合相体系,具有液相伤害小、造缝携砂性能好、现场操作性强等特点,可满足大砂量、高砂比压裂施工要求。该技术在冀东油田南堡5号构造深层致密砂岩气藏进行先导试验,压后单井日增油2.5倍,日增气8.6倍,增产效果理想。      

Oxidative Desulfurization of Dibenzothiophene Catalyzed by VO(acac)2 in Ionic Liquids at Room Temperature

A simple extraction and catalytic oxidative desulfurization (ECODS) system composed of VO(acac)₂, 30% H₂O₂, and 1-butyl-3-methylimidazolium tetrafluoroborate ([Bmim]BF₄) has been found to be suitable for the deep removal of dibenzothiophene (DBT) in model oil at room temperature. The optimal conditions were as follows: [n(H₂O₂)/n(DBT)/n(catalyst) = 100:20:1], model oil = 5 mL, ionic liquid [IL] = 1 mL, T = 30°C, t = 2 hr. With the ECODS system, the sulfur removal of DBT could reach 99.6%, which was superior to that of the simple extraction with IL (15.6%) or oxidation without catalyst (17.1%). The IL could be recycled five times without a significant decrease in activity.