Ce~(4+)改性阳离子交换树脂催化环氧化反应的研究

以732#强酸性阳离子交换树脂为载体,采用离子交换法合成了Ce4+改性离子交换树脂催化剂,考察了Ce4+浓度、吸附温度和pH值等因素对树脂改性的影响,并测试了催化剂的重复使用性能。结果表明,当Ce4+浓度为0.1mol/L左右,常温25℃、pH值接近中性时,Ce4+改性阳离子交换树脂的催化活性最佳,且重复使用6次仍保持较高的催化活性。试验利用红外光谱(FT-IR)、热重分析(TG)和能谱仪(EDS)等对改性树脂的结构进行分析表征,结果表明,改性后的树脂中氢元素大部分被Ce4+离子所替代,其酸性和稳定性均有所提高。将Ce4+改性732#阳离子交换树脂作为催化剂应用于生物柴油环氧化反应中,产物环氧值较高。     

强酸性离子交换树脂催化合成联苯乙酸乙酯

考察了几种强酸性离子交换树脂对联苯乙酸酯化反应的活性,结果表明,D001-CC型号的强酸性离子交换树脂对合成联苯乙酸乙酯的反应催化活性高,联苯乙酸的转化率可达88.7%,同时它的回收容易,重复使用性能好。同时考察了反应条件对酯化反应收率的影响,获得了该反应的优化条件。     

微波辐射下润滑油类双季戊四醇六酯的合成

世界能源危机的出现，使合成润滑油的研究得到迅速发展。合成润滑油与矿物油相比，以其挥发性低、节省能耗、低温性能好、热氧化安定性好、使用寿命长等优点广泛用于军事、航空、机械等领域。随着高科技密集现代航空器的发展和环保要求的不断提高，国际上对润滑油的性能要求日益苛刻。合成酯类润滑油因其独特的高低温性能、粘温性能、润滑性能、无毒、可生物降解性能被广泛用作航空燃气涡轮发动机润滑油、仪表油、压缩机润滑剂的基础油，被称为环境友好的基础油。     

不同类型阴离子交换树脂对Cr(Ⅵ)的吸附性能研究

通过静态吸附实验、动力学实验,从3种吸附去除Cr(Ⅵ)的离子交换树脂中优选出DEX-Cr树脂,研究了pH、温度对其交换性能的影响,进一步对树脂的动态吸附-再生性能和重复使用稳定性进行了考察。结果表明DEX-Cr树脂对Cr(Ⅵ)的吸附去除效果好,且重复使用稳定性高,可以作为分离去除Cr(Ⅵ)的高效吸附剂。     

新型环氧丙烯酸树脂增韧剂的合成

用马来酸酐和聚乙二醇1000合成具有反应活性端基的聚乙二醇,用红外与核磁共振进行了表征,并用其对环氧丙烯酸树脂进行改性;研究反应温度、反应时间对反应及产物性能的影响;用红外对反应性聚乙二醇和环氧丙烯酸树脂的固化物进行分析.结果表明,反应性聚乙二醇参与了环氧丙烯酸树脂的固化反应,可在交联网络中构成不同长度的柔性链段,显著地提高了环氧丙烯酸树脂的冲击强度.     

Co/SiO2催化剂催化费托合成中CeO2助剂的作用

 在Co/SiO2催化剂中加入少量CeO2助剂, 能够提高其催化费托(FT)反应的活性和液态烃(Ｃ5+)的选择性,特别是可以生成优质的高附加值柴油及润滑油基础油(C12+), 但助剂CeO2对Co/SiO2催化剂的作用目前仍存在争议. 本文利用X射线衍射、程序升温还原、程序升温脱附、程序升温表面反应、 X射线光电子能谱、扫描电镜和同位素脉冲反应结合H-D同位素交换等方法对催化剂进行了表征,并采用微反评价考察了催化剂的催化性能. 表征结果表明,少量CeO2助剂的添加提高了活性组分Co在催化剂表面的分散度,降低了催化剂表面Co的晶粒度,使催化剂对CO和H2的吸附性能发生了改变. 同位素脉冲反应结合H-D交换实验表明, CeO2的添加减弱了Co的金属性,提高了其吸附解离氢的能力和CO吸附量,增大了催化剂表面活性碳物种的浓度和聚合趋势,使FT合成的碳链增长几率增大至0.90, 产物中液态烃选择性和重质烃含量明显增加,说明CeO2的加入有利于生成高附加值的柴油和润滑油基础油.     

硫酸氢季铵盐催化环氧化物和氮杂环丙烷的醇解反应

利用四丁基硫酸氢铵(TBAHS)和大孔树脂(D201型)支载的硫酸氢季铵盐(D201-HSO4), 分别催化环氧化合物或氮杂环丙烷与甲醇的开环反应, 以高产率得到β-甲氧基醇或β-甲氧基胺. 两种催化剂对该反应都很有效, 但大孔树脂支载的硫酸氢季铵盐(D201-HSO4)易于制备, 并可以重复使用.     

基于植物油的润滑油基础油及添加剂合成研究

综述了植物油用作润滑油基础油的改性方法,包括提高植物油中油酸含量的生物改性方法、减少植物油分子不饱和度和提高植物油分子支化度的化学改性方法以及加入硼酸类添加剂或氮化硼纳米粒子等添加剂改性方法;通过在植物油分子中引入功能性官能团以及与其他单体聚合等方法可由植物油合成润滑油添加剂,提高油品的增黏、降凝和抗磨等性能。      

生物柴油调合对其低温流动性能的改善

为了了解生物柴油中脂肪酸甲酯组成对其低温流动性能的影响,探索改善其流动性能的方法,以大豆油、花生油和牛油为原料合成了大豆油甲酯、花生油甲酯和牛油甲酯,测定了它们的脂肪酸甲酯组成和低温流动性能.结果表明,长碳链饱和脂肪酸甲酯的含量是影响生物柴油低温流动性能的主要因素.通过对混合生物柴油流动性能的测定,发现可以通过不同来源...     

表面亲水性粒度单分散交联PMMA树脂的合成及表征

用种子溶胀聚合方法 ,合成出了粒度单分散的交联聚甲基丙烯酸甲酯微球 .将微球通过水解 ,使其转化为表面带羧基的树脂 .分别用多糖化合物Dextran和DEAE Dextran对水解树脂表面进行包覆涂层 ,然后用n 丁二醇双环氧丙醚分别进行交联 ,制备出两种表面带高交联多糖覆盖层的树脂 .以两种改性树脂为填料 ,以人血清蛋白为试样 ,用HPLC方法对树脂的亲水性能进行了表征 .研究表明 ,两种改性树脂均有很好的亲水性 ,蛋白质的回收率分别在 97%和 99%以上 ,并有良好的机械强度和化学稳定性     

超声波辅助固体酸催化塔尔油脂肪酸制备生物柴油

将强酸性阳离子交换树脂加入塔尔油脂肪酸和甲醇混合液中,并在超声波辐射辅助下得到生物柴油,对生物柴油的制备工艺和性能进行研究,同时建立动力学模型。结果表明,超声波辐射的辅助强化,能有效提高生物柴油的得率;在反应温度65℃、反应时间1h、甲醇与TOFA摩尔比为10∶1、脱水剂用量为TOFA6%、树脂NKC-9用量为TOFA40%的最佳工艺条件下,反应平衡常数可达11.18,生物柴油得率为90.0%。建立的动力学模型补充了超声波辐射辅助酯化反应动力学参数,并用此模型解释了各工艺参数呈现的规律。以廉价的制浆黑液回收物塔尔油脂肪酸为原料制备生物柴油,能有效地降低生物柴油价格,提高其市场竞争力,实现塔尔油高附加值利用,具有良好的发展前景。     

Assessment of the oxidative stability of lubricant oil using fiber-coupled fluorescence excitation–emission matrix spectroscopy

The fluorescence of antioxidant additives in lubricant oil was used as an indicator of oxidative stability of the oil. It was found that the decrease in fluorescence intensities of phenyl-α-napthylamine, its dimer, and another unidentified antioxidant coincide with the formation of decomposition products of the oil base stock. Simple kinetic models were developed that were capable of describing antioxidant reactions as a pseudo first-order processes. It is shown that fluorescence excitation emission matrix (EEM) spectroscopy coupled with an optical fiber probe can provide real-time assessment of the oxidative stability of the lubricant. Parallel factor (PARAFAC) analysis was used to correlate the component scores to the oil breakdown number.     

Chemical modification of waste cooking oil for the biolubricant production through transesterification process

Concerns and restrictions around contamination and environmental pollution are developing. The production of waste cooking oil and the pollution brought on by mineral oils are two important issues. The FSSAI's new standards state that cooking oil that contains more than 25% polar compounds is inappropriate for use and should be discarded. Therefore, both issues can be resolved with the aid of chemical modifications to waste cooking oil. Waste cooking oils are an attractive alternative to mineral oils because they are biodegradable and renewable sources of lubricants. The goal of the current research work is to create an environmentally friendly lubricant through transesterification reaction. Fatty acid methyl esters (FAMEs) of WCO with various alcohols (1-Heptanol, 2-Ethyl-1-Hexanol & Neopentyl Glycol) with diverse branching were used to create bio lubricant. As a heterogeneous catalyst, zinc acetate was used to carry out the reaction. Complex esters, which have been produced, have the potential to be used as biodegradable lubricants in industrial lubricant applications. Using the GC-MS technique, the structure of the generated bio lubricant was examined. The structural modification of waste cooking oil resulted in improvement in both physicochemical and tribological properties. The created bio lubricant had improved flash and fire points as well as a superior viscosity index (>120). The generated bio lubricant possesses friction characteristics that are comparable to those of commercial mineral oil-based lubricants. According to the results of this study, waste cooking oil lubricant has a lot of potential for use as a base stock due to its favorable biodegradability and tribological performance.     

Montmorillonite-supported KF/CaO: a new solid base catalyst for biodiesel production

Biodiesel is an alternative to petroleum-derived diesel fuel; development of a high-efficiency base catalyst to be used in heterogeneous biodiesel production is still a challenge. In this paper, a novel solid base catalyst, KF- and CaO-supported montmorillonite (KCa/MMT) was successfully synthesized by a facile impregnation method, and used for producing biodiesel in transesterification of commercial soybean oil with methanol. The catalysts were characterized by X-ray diffraction, carbon dioxide temperature-programmed desorption and scanning electron microscopy. Effects of the parameters, such as the loading amount of KF, the amount of KCa/MMT, and the methanol to oil molar ratios, on the yield of biodiesel were investigated. A maximum biodiesel yield of 98 % was obtained under the optimal reaction conditions. The separated catalyst can be directly used in the next round of reactions and gave a satisfactory yield. Furthermore, analysis of the catalyst's tolerance to oil-containing water or free fatty acids, and a kinetic study were also carried out. Koros–Nowak tests were designed and conducted, and it was proven that the heat and mass transfer were not limited by the reaction rate.     

CaO-MgO@CoFe_2O_4磁性固体碱的制备及其大豆油酯交换反应催化性能

以草酸盐为前驱体采用两步法制备了一种以CaO-MgO作为活性组分,以CoFe_2O_4作为磁核的磁性固体碱催化剂,并用于大豆油与甲醇的酯交换反应合成生物柴油。对制备的磁性固体碱催化剂进行了磁滞回线、X-射线衍射(XRD)、CO_2-TPD及透射电镜(TEM)表征。考察了不同核壳物质的量比、焙烧温度、反应温度、反应时间、醇油物质的量比以及催化剂用量等因素对大豆油转化为生物柴油产率的影响。结果表明,采用核壳物质的量比为1∶6、焙烧温度为700℃所制备的CaO-MgO@CoFe_2O_4催化剂,当醇油物质的量比为12、催化剂用量为大豆油质量的1.0%时,在65℃下反应时间3 h,生物柴油收率高达97.1%。该催化剂具有较好的重复利用性能,重复利用四次后生物柴油的收率仍可达90%。     

Biodiesel Production via the Transesterification of Soybean Oil Using Waste Starfish (Asterina pectinifera)

Calcined waste starfish was used as a base catalyst for the production of biodiesel from soybean oil for the first time. A batch reactor was used for the transesterification reaction. The thermal characteristics and crystal structures of the waste starfish were investigated by thermo-gravimetric analysis and X-ray diffraction. The biodiesel yield was determined by measuring the content of fatty acid methyl esters (FAME). The calcination temperature appeared to be a very important parameter affecting the catalytic activity. The starfish-derived catalyst calcined at 750 °C or higher exhibited high activity for the transesterification reaction. The FAME content increased with increasing catalyst dose and methanol-over-oil ratio.     

离子交换树脂催化合成甲基丙烯酸莰醇酯

以大孔强酸性离子交换树脂为催化剂合成甲基丙烯酸莰醇酯。研究了催化剂种类、用量及反应温度诸因素对反应的影响。实验结果表明，D001-cc树脂催化效果较好;树脂用量增加、反应温度提高均可提高反应速度;该树脂可反复使用。还研究了反应动力学，确定其为二级反应，求得其表观活化能为13.81千卡／摩尔。     

Preparation and catalytic performance of quaternary ammonium base resin for methanolysis of natural phosphatidylcholine

The most acceptable method for preparing glycerophosphocholine is to hydrolyse the natural phosphatidylcholine and use the quaternary ammonium base resin, as a promising heterogeneous catalyst can simplify the craft and minimise the problems existing in the homogeneous catalytic process. However, most of the resins reported in the literature are commercial trimethyl benzyl ammonium base resins and the application of other longer carbon-chain quaternary ammonium resins has not been reported. In the present work, a series of quaternary ammonium base resins were prepared from chloromethyl polystyrene microspheres and different tertiary amines and were used to prepare glycerophosphocholine from natural phosphatidylcholine. The factors affecting the exchange capacity and activity of the resin were investigated. The results showed that the resin possessed a better activity and stability under the following conditions: 1,4-dioxane as solvent, triethylamine as amination agent, reaction temperature of 60°C and amination time of 3 h; it was then used in the methanolysis of phosphatidylcholine by ultrasound-assisted reaction at ambient temperature, with the conversion of phosphatidylcholine attaining 97 % after 4 h. The catalyst was easy to separate from the reaction mixture and could also be readily available for repeat use; the activity and stability were largely consistent after six repeat uses.     

Comparative study of oxidative stability of sunflower and cotton biodiesel through P-DSC

Biodiesel can contain unsaturated fatty acids, which are susceptible to oxidation, being able to change into polymerized compounds. Oxidative stability is very important in the quality control of oils and biodiesel. In this study, biodiesel samples were produced through the methyl route, using a homogeneous catalyst. The determination of methyl esters was performed by gas chromatography in order to confirm the conversion of the carboxylic acids present in the raw material for the methyl esters. Also proved the presence of methyl linoleate and methyl oleate to the major constituent of biodiesel. The thermal and oxidative stability of sunflower and cotton oils and their biodiesel, using TG and P-DSC techniques were investigated. The use of P-DSC to measure the oxidative induction time was very important. These measurements were used to evaluate the cotton and sunflower oils, and their respective biodiesel. It was found that the thermal-oxidative stability of vegetable oils and their biodiesel were similar, due to the fact that both presented chemical composition and percentages of fatty acids similar.     

CH4-CO2 reforming to syngas over Pt-CeO2-ZrO2/MgO catalysts: Modification of support using ion exchange resin method

Pt-CeO2-ZrO2/MgO (Pt-CZ/MgO) catalysts with 0.8 wt% Pt, 3.0 wt% CeO2 and 3.0 wt% ZrO2 were prepared by wet impregnation method. Support MgO was obtained using ion exchange resin method or using commercial MgO. XRD, BET, SEM, TEM, DTA-TG and CO2-TPD were used to characterize the catalysts. CH4-CO2 reforming to synthesis gas (syngas) was performed to test the catalytic behavior of the catalysts. The catalyst Pt-CZ/MgO-IE(D) prepared using ion exchange resin exhibits more regular structure, smaller and more unique particle sizes, and stronger basicity than the catalyst Pt-CZ/MgO prepared from commercial MgO. At 1073 K and atmospheric pressure, Pt-CZ/MgO-IE(D) catalyst has a higher activity and greater stability than Pt-CZ/MgO catalyst for CH4-CO2 reforming reaction at high gas hourly space velocity of 36000 mL/(g·h) with a stoichiometric feed of CH4 and CO2. Activity measurement and characterization results demonstrate that modification of the support using ion exchange resin method can promote the surface structural property and stability, therefore enhancing the activity and stability for CH4-CO2 reforming reaction.