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21.
经不同时间沉降而得的精制原料土制备交联膨润土,发现用沉降30分钟而得的精制原料土制备的交联膨润土催化活性较好.测定了不同焙烧温度和焙烧时间对交联臌润土裂化活性的影响,用XRD分析了不同焙烧温度、OH/Al(摩尔比)比值对d(001)峰的影响.用IR,D1A,BET手段表征了交联膨润土的物化特性。实验结果表明用山西浑源膨润土制备的交联膨润土是一种良好的催化裂化催化剂材料。 相似文献
22.
Linear alkylbenzene sulfonic acid, the largest-volume synthetic surfactant, in addition to its excellent performance, is important
due to its biodegradable environmental friendliness, as it has a straight chain and is prepared by the sulphonation of linear
alkylbenzenes (LAB). To ensure environmental protection, the commercial benzene alkylation catalysts HF or AlCl3 are replaced and we have developed a clean LAB production process using a pillared clay catalyst capable of not only replacing
the conventional homogeneous catalysts, but also having high selectivity for the best biodegradable 2-phenyl LAB isomer. Pillared
clay catalysts having high Br?nsted acidity show efficient conversion in gas phase alkylation of benzene with 1-octene with
a good 2-phenyl octane selectivity. 相似文献
23.
用羟基铝聚合物和它的金属同晶取代物交联临安产的蒙脱土。结果表明仅Fe~(3+)同晶取代了柱中Al~(3+)离子。这种新催化剂在异丙苯裂解时呈现较好的活性且能使丙烯二聚,随即发生环化脱氢的特性。浸渍上钯后,使正己烷加氢异构活性增加。从产物分布可知,此催化剂的异构物选择性很高。 相似文献
24.
Al-pillared, Fe-pillared and mixed Fe-Al pillared systems have been prepared and characterized using EDX and XRD analyses,
surface area pore volume and acidity measurements. Mixed systems are found to be superior to single oxide pillared systems
in terms of acidity and aniline methylation activity.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
25.
Xiong-feng Zeng Jian-sheng Wang Ying-na Zhao Wen-li Zhang Meng-huan Wang 《矿物冶金与材料学报》2021,28(3):503-510
We successfully constructed TiO2-pillared multilayer graphene nanocomposites (T-MLGs) via a facile method as follows: dodecanediamine pre-pillaring, ion exchange (Ti4+ pillaring), and interlayer in-situ formation of TiO2 by hydrothermal method. TiO2 nanoparticles were distributed uniformly on the graphene interlayer. The special structure combined the advantages of graphene and TiO2 nanoparticles. As a result, T-MLGs with 64.3wt% TiO2 showed the optimum photodegradation rate and adsorption capabilities toward ciprofloxacin. The photodegradation rate of T-MLGs with 64.3wt% TiO2 was 78% under light-emitting diode light irradiation for 150 min. Meanwhile, the pseudo-first-order rate constant of T-MLGs with 64.3wt% TiO2 was 3.89 times than that of pristine TiO2. The composites also exhibited high stability and reusability after five consecutive photocatalytic tests. This work provides a facile method to synthesize semiconductor-pillared graphene nanocomposites by replacing TiO2 nanoparticles with other nanoparticles and a feasible means for sustainable utilization of photocatalysts in wastewater control. 相似文献
26.
L. M. Gandía M. A. Vicente P. Oelker P. Grange A. Gil 《Reaction Kinetics and Catalysis Letters》1998,64(1):145-151
A Na-montmorillonite was intercalated with manganese- and samarium-manganese-aluminium solutions. The pillared montmorillonites
were characterized by X-ray diffraction and nitrogen adsorption. The presence of manganese and samarium-manganese citrates
in the intercalation process modify the distance between the clay sheets and the microporous structure of the pillared montmorillonites. 相似文献
27.
ChunHuiZHOU ZhongHuaGE XiaoNianLI HongQiangGUO JianSUN 《中国化学快报》2003,14(12):1285-1288
A mesoporous titanium/silicon -containing montmorillonite-based catalytic materials has been synthesized by novel gallery-templated techniques. XRD, SEM, framework IR, and N2 adsorption-desorption isotherms provided evidence of the formation of Si/Ti pillars. The synthetic materials show potential catalytic application for hydroxylation of phenol with peroxide. 相似文献
28.
Mono-substituted Keggin ions PW11O39Cr(H2O)4 , PW11TiO403 and PW11VO404 were intercalated between the layers of the clay of anions of Zn-Al type using the ion exchange method to obtain a new type of pillared layered microporous materials ZnAl-PW11Cr, ZnAl-PW11Ti and ZnAl-PW11V with basal spacing (1.48±0.02) run. On the basis of the MAS NMR results of 27A1 and 31P, a steric pillared layered structure model of orientation localization of PW11VO40,4- in the orientation in which the C2 axis of PW11VO404-is perpendicular to the host layer. It has been found that this kind of pillared layered microporous materials possess a higher catalytic activity for the esterification of acetic acid with n-butanol than H-type molecular sieves. 相似文献
29.
采用羟基铁离子柱撑Na-Mont制备出1.0Fe-PILC,通过超声浸渍法合成不同铜负载量的nCu-Fe-PILC,并测试了其在富氧条件下催化C_3H_6选择性催化还原NO的性能。通过N_2吸附脱附、XRD、UV-Vis、H_2-TPR、Py-FTIR等技术手段表征催化剂的微观结构和物化性质,进一步解释其催化反应机理。结果表明,Cu的引入提高了1.0Fe-PILC的中低温活性和抗水硫能力。其中9Cu-Fe-PILC在300℃时NO转化率可达69.8%以上,400℃后NO转化率保持在99%以上且水硫影响较小。XRD、N_2吸附脱附结果表明,催化剂的SCR活性与所负载的活性组分和催化剂的吸附能力有关。UV-Vis结果表明,9Cu-Fe-PILC具有较强的中低温活性,与其含有较多的游离态Cu~(2+)有关。H_2-TPR结果表明,与1.0Fe-PILC相比,经Cu修饰的nCu-Fe-PILC获得了中低温还原能力。Py-FTIR结果表明,nCu-Fe-PILC表面同时含有Lewis酸和Br?nsted酸,Lewis酸是影响催化剂SCR活性的主要因素。 相似文献
30.
Yu Ye Libo Sun Chenghui Zhang Jianfeng Du Yuchuan Liu Xiaowei Song Zhiqiang Liang 《应用有机金属化学》2019,33(12)
A novel luminescent metal–organic framework ( Zn‐TCPP/BPY ) with pillared structure based on 2,3,5,6‐tetrakis(4‐carboxyphenyl)pyrazine (H4TCPP) and 4,4′‐bipyridine (BPY) has been designed and synthesized through a solvothermal reaction. The [Zn2(COO)4] paddlewheel units are linked by TCPP4? ligands to form two‐dimensional layers and further connected by BPY ligands as pillars to construct the twofold interpenetrating three‐dimensional framework. Interestingly, Zn‐TCPP/BPY possesses outstanding stability in organic solvents and water as well as maintains its structural rigidity in aqueous solutions of different pH values (3–12). After activation, Zn‐TCPP/BPY possesses permanent porosity with Brunauer–Emmett–Teller surface area of 630 m2 g–1. Remarkably, Zn‐TCPP/BPY displays excellent fluorescent property in virtue of the aggregation‐induced emission effect of the H4TCPP ligand, which can be highly active and quenched by small amounts of 2,4,6‐trinitrophenol (TNP) and Fe3+ ions. Furthermore, the detection effect of Zn‐TCPP/BPY remains basically the same even after five cycles. The excellent stability, high sensitivity, and recyclability of Zn‐TCPP/BPY make it an outstanding chemical sensor for detecting TNP and Fe3+ ions. 相似文献