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固体超酸POSA催化醇脱水制烯 总被引:1,自引:0,他引:1
固体超酸由于其优良的催化性能,近年来倍受重视。其中以全氟骨架的磺酸树脂Nafion H应用最广。POSA(全氟辛基磺酸,C_8F_(17)SO_3H)也是一种化学性质稳定、易回收的固体超酸,具有与Nafion H相似的氟碳链磺酸结构。 相似文献
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7-氢-全氟-(4-甲基-3,6-二氧杂辛基磺酰氟)(1)在氧化铝-氧化铜-氧化铁催化剂存在下发生热裂解反应。230℃左右脱去磺酰氟,生成7-氢-全氟-(4-甲基-3,6-二氧杂辛烷)(2),而没有得到脱HF的产物。在相同条件下,全氟-1,10-二氟磺酰基-3,8-二氧杂癸烷(3)热裂解生成全氟-3,8-二氧杂癸基磺酰氟(5)。在245℃以上时,还生成全氟-3,8-二氧杂癸烷(4)。对催化剂组成和裂解温度与产物得率间的关系也进行了研究。该催化剂还能使含有磺酰氟基团的全氟高分子薄膜表面部份地脱除磺酰氟。产物的结构均由红外、核磁、质谱及元素分析鉴定。 相似文献
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全氟辛基磺酸(POSA,perfluorooctanesulfonic acid)是一个熔点90℃的固体超酸,测定POSA酸度函数H_0值是一个一直未能解决的问题。G.A.Olah将所有全氟烷基磺酸C_nF_(2n 1)SO_3H都划归超酸范围,但迄今只有液态和低熔点固态的C_1、C_2、C_4和C_6的全氟烷基磺酸测定过H_0值,因而测定POSA酸度函数H_0值的意义不仅在于首次测出了POSA酸度函数H_0的确切数值,明确了POSA确系酸度比百分之百硫酸更强的超酸,而且开辟了C_7以上固体全氟烷基磺酸H_0的测定方法和途径,进而可以建立这一全氟烷基同系列的酸度函数H_0值的线性关系、结构影响等。 相似文献
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固体超强酸AlCl3.Fe2(SO4)3的研究 总被引:2,自引:0,他引:2
自60年代末Olah等人研究液体超强酸以来,超强酸的催化作用的研究迅速发展。由于多相催化比均相催化具有许多优越性,人们对固体超强酸催化剂进行了广泛的研究。Ma-gnatta等报道AlCl_3与聚苯磺酸络合物在85℃下,能使已烷裂解异构化。Olah等发展了全氟磺酸树脂Nafion-H固体超强酸催 相似文献
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《燃料化学学报》2021,(10)
以正己烷为模型化合物,通过产物分布分析,探讨HZSM-5分子筛上烷烃酸催化裂解反应路径及机理。研究结果表明,反应温度为300℃,不存在热裂解过程的条件下,只有基于碳正离子机理的酸催化反应。催化剂裂化活性与B酸(Br(o|")nsted acid)量成正相关。由裂解产物的分布特点,其中,丙烯的选择性与催化剂硅铝比和剂油比正相关,而乙烷、乙烯和丙烷的选择性呈负相关性,证实了低酸密度有利于单分子裂解路径的进行。值得注意的是,正己烷直接裂解所得C_4产物的总选择性明显高于C_2产物,结合量化计算,证实正己烷裂解生成的C_2H_5~+碳正离子难以通过氢转移反应生成乙烯和乙烷,而是更倾向于与正己烷分子形成新的碳鎓离子(C_8H_(19)~+,继续发生裂解反应生成更多C_4产物,揭示了轻烃催化裂解产物中乙烯选择性低的理论本质。综上可知,通过改变催化剂酸密度和剂油比,可实现反应路径的控制,从而调控轻烃酸催化裂解产物的选择性。本研究可为石脑油催化裂解催化剂和工艺开发提供重要的理论支撑。 相似文献
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选择环氧树脂E51作为改性填料,制备出一系列不同树脂质量分数(0%、2%、4%和6%)的发光树脂透水混凝土。环氧树脂的引入使发光树脂透水混凝土的抗压强度和抗折强度均得到了提高,且随着树脂掺量的增加呈现出先升高后降低的趋势,在树脂质量分数为4%时,抗压强度和抗折强度均达到最大值21.7和6.11 MPa,发光树脂透水混凝土的透水系数随着环氧树脂质量分数的增加呈现出先降低后升高的趋势,在4%时透水系数最低为5.1 mm/s。微观形貌分析发现未经改性的环氧树脂透水混凝土的断面处有明显的裂痕和气孔,整体结构较为疏松,在引入环氧树脂后,裂痕和气孔的数量明显减少,整体结合较为紧密,发光树脂透水混凝土的发光时间与树脂质量分数关系不大,且发光透水混凝土在光照1 h下可以保持超过5 h的较为高效的发光时间。 相似文献
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Polystyrene-supported N-phenyl-N-acyl sulfonamide resin was prepared by reacting polystyrene sulfonyl chloride resin with aniline and acylating in pyridine with either acid chlorides or anhydrides. Then, this resin was utilized as a new type of acyl transfer reagent to synthesize the amide library. It was approved to be a more effective acyl transfer reagent with higher amide yields than the polystyrene-supported N-methyl-N-acyl sulfonamide resin and N-benzyl-N-acyl sulfonamide resin. When the phenyl group bonded to the N atom on N-phenyl-N-acyl sulfonamide resin was substituted by the electron withdrawing group or electron donating group, a decreasing amide yield was obtained. N-phenyl-N-acyl sulfonamide resin could be regenerated many times. 相似文献
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The effect of MWNTs on the microstructure of resin carbon and thermal conductivity of C/C composites 总被引:1,自引:0,他引:1
Multi-walled nanotubes were added into furan resin. Unidirectional carbon/carbon preforms were densified with the nanotube-doped furan resin by impregnation–carbonization cycle. The effects of Multi-walled nanotubes on the microstructure of resin carbon and thermal conductivity of carbon/carbon composites were investigated. The results show that Multi-walled nanotubes can induce the ordered arrangement of planar carbon microlites in resin carbon during high-temperature treatment and enhance the graphitization degree of resin carbon. Small amount of Multi-walled nanotubes in resin carbon can enhance the thermal conductivity of C/C composites evidently, especially the thermal conductivity vertical to the direction of fiber axis, due to the improvement of microstructure of resin carbon. Excess Multi-walled nanotubes in resin are disadvantageous to the enhancement of thermal conductivity instead, because they are difficult to disperse and easy to agglomerate, resulting thermal resistances in carbon matrix. 相似文献
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Catechol-type chitosan resin and salicylic acid-type chitosan resin were easily synthesized for use in estimating the adsorption behavior of 34 elements at pH 1 - 7 in aquatic media. The catechol-type chitosan resin could adsorb Cu(II) at pH 3 - 7, In(III) at pH 4 - 6, Pb(II) and lanthanoids at pH 5 - 7, and U(VI) at pH 4 - 7 more effectively than the salicylic acid-type chitosan resin and the cross-linked chitosan resin (base material). Adsorption ability was in the order: catechol-type chitosan resin > salicylic acid-type chitosan resin > cross-linked chitosan resin. 相似文献
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Jaya Mohandas V. Srinivasa Rao N. Vijayakumar T. Kumar S. Velmurugan S. V. Narasimhan 《Journal of Radioanalytical and Nuclear Chemistry》2014,302(3):1185-1188
The removal of uranium and americium from nitric acid solutions by sulphonated phosphinic acid resin has been investigated. The capacity of the sulphonated resin exceeds the capacities of phosphinic acid resin and commercial cation exchange resin. Other advantages of the sulphonated resin for uranium and americium removal include reduced sensitivity to acidity and inert salt concentration. 相似文献
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新型酰乙基葡甲胺树脂的合成及吸硼性能 总被引:1,自引:0,他引:1
采用一步法, 用氯乙酰化聚苯乙烯树脂(PS-Acyl-Cl)与葡甲胺反应制得一种同时含有α-酰乙基胺和邻羟基双官能团的新型酰乙基葡甲胺树脂, 考察了溶液pH值、 温度、 初始浓度和吸附时间对酰乙基葡甲胺树脂吸附硼的影响. 结果表明, 在实验浓度范围内, 该树脂对硼的吸附符合Langmuir方程, 最大吸附量约为28.1 mg/g干树脂, 优于氯甲基树脂制得的硼特效树脂. 表明α-酰乙基胺和邻羟基双官能团对硼有双重或协同吸附作用. 该树脂在pH=6.0时对硼的吸附量最大; 温度对树脂吸附的影响不大; 树脂解吸率大于96%; 树脂重复使用5次后吸附量基本不变. 动力学研究结果表明, 吸附过程为液膜扩散控制过程. 相似文献
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不同温度处理的糠醇和聚苯胺树脂碳化产物结构基因变化的红外光谱研究 总被引:2,自引:0,他引:2
红外光谱测试结果表明糖醇树脂碳化过程中五员杂环上的碳氧键首先发生断裂,使氧脱出,而剩余的双烯链状结构再进行重排,形成六员稠环结构,并在此基础上发生脱氢反应生成石墨微晶。测试结果还表明聚苯胺树脂中的氮在碳化过程中的稳定性与其相连结的基团结构有密切关系。苯环相连的氮比与苯酚基相连的氮具有更强的抗热解稳定性。聚苯胺碳化产物中的氢主要分为两大类:一类是以碳氢键的形式存在;另一类则是以氮氢键的形式存在。碳化产物中的氢主要是在苯的稠环结构上以碳氢键形式存在。 相似文献
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Preparation of magnetic anion exchange resin and their adsorption kinetic behavior of reactive blue 总被引:1,自引:0,他引:1
Magnetic anion exchange resin(MD-1) was prepared from quaternization of magnetic copolymeric resin(glycidyl methacrylate -eo-divinylbenzene).For comparison,magnetic resin MD-0 without quaternization and non-magnetic resin(D-1) were also synthesized for the adsorption process.It was found that the adsorption was mainly contributed to the chemical interaction between quaternary ammonium groups and reactive blue RXHC.Due to the smaller size,MD-1 had faster adsorption and desorption kinetics than D-1.Coupled with the advantage of easy separation,the magnetic anion exchange resin was considered to be superior to common anion exchange resin in removal of reactive dye. 相似文献