共查询到20条相似文献,搜索用时 359 毫秒
1.
2.
3.
介绍了乙二醇单甲醚的合成方法。报道了其合成工艺技术方面的新进展, 如新的催化剂NKC- 01 、NKC- 1A、MTZ、杂多酸等。论述了其在各行业的应用、市场情况。 相似文献
4.
The present study showed enhanced activities of ethylene/1-octene copolymerization via TiO2–SiO2 mixed oxides-supported MAO with a zirconocene catalyst. It was proposed that titania was decorated on silica surface and acted as a spacer to anchor MAO to the silica support resulting in less steric hindrance and less interaction on the support surface. 相似文献
5.
MgF2基催化剂合成CH2F2的研究 总被引:1,自引:2,他引:1
用混合法制备了一系列含Cr3+和过渡金属助剂的MgF2基催化剂。考察了助剂对CrF3/ MgF2 催化剂氟化CH2Cl2的催化性能,结果表明,在Cr3+/ MgF2中添加一定的Co2+和Ni2+能提高催化剂稳定性,延长使用寿命;Zn2+能提高CH2F2的选择性;Fe3+和Cu2+对Cr3+/ MgF2的活性有抑制作用。讨论了配料比、空速和温度等反应条件对催化剂性能的影响。 相似文献
6.
7.
8.
9.
以硝酸锆为主要原料,采用酸浸渍法制得SO4^2-/ZrO2-SiO2固体超强酸,对主要影响其催化活性的焙烧温度进行了考察,并将制得的SO4^2-/ZrO2-SiO2作催化剂,合成了丁酸异戊酯,确定了最佳工艺条件。实验表明制得的该催化剂具有较高的催化活性,用其催化合成丁酸异戊酯其收率达93%。 相似文献
10.
Thin films of magnesium vanadates oriented to expose a single crystalline face, could potentially serve as ideal models for high surface area magnesium vanadate catalysts for oxidative dehydrogenation. The growth of oriented films of one particular magnesium vanadate phase, the orthovanadate (Mg3(VO4)2), has been achieved by rf sputter deposition of the orthovanadate onto Au(111) surfaces. X-ray diffraction, Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy have been used to investigate the structure and composition of the films. The orthorhombic orthovanadate grows epitaxially with the (021) plane oriented parallel to the surface. By varying oxygen flow rates during deposition the stoichiometry of the films can be varied from fully oxidized to highly oxygen deficient. At very low oxygen flow rates or in the complete absence of oxygen, a reduced Mg3V2O6 phase is formed. This reduced phase has a cubic structure and grows with the (100) plane parallel to the surface. 相似文献
11.
12.
采用工业钛白粉作为烟气脱硝催化剂的载体原料,通过添加助剂M对其改性,研制出了一种V2O5-WO3/Ti O2烟气脱硝催化剂,并确定助剂M的最佳量为质量分数10%;同时考察了焙烧温度对该催化剂比表面积及脱硝性能的影响,确定了最佳焙烧温度为500℃;最佳活性组分钒含量为质量分数1.5%,稳定助剂钨含量为质量分数8%的催化剂性能最好。 相似文献
13.
14.
15.
采用共沉淀法制备S2O^2-8/ZrO2-Al2O3-SiO2固体超强酸催化剂。通过单因素实验考察了三种金属最佳配比、陈化时间S2O^2-8的最佳浓度、浸泡时间、焙烧温度、焙烧时间等对固体酸酸强度的影响。研究表明,固体超强酸S2O^2-8/ZrO2-Al2O3-SiO2的最佳制备条件是:n(Zr):n(Al):n(Si)=1:2:1,陈化时间5h,S2O^2-8的浓度为0.75mol/L,浸渍时间3h,焙烧温度400℃,焙烧时间4h。此外,还利用红外光谱对样品结构进行了表征,利用酯化反应对其催化活性进行了初步研究。 相似文献
16.
研究了Ag/Cu/CeO2-ZrO2催化剂在富氧条件下C3H6选择性还原NO的性能,讨论了载体中铈锆比例,催化剂活性组分的负载方式以及在载体中加入适量碱土金属对催化剂反应活性的影响,结果表明铈锆比为1:3时,催化剂活性最好,NO转化率达到58.2%。在铈锆比为3:1的CeO2-ZrO2载体上,单独负载Cu的催化剂活性最好,NO转化率为53.8%。在CeO2-ZrO2载体中加入少量Ca可明显改善催化剂性能,拓宽催化剂反应温度范围。 相似文献
17.
Yusaku Takita Jun-ichi Moriyama Hiroyasu Nishiguchi Tatsumi Ishihara Fusakazu Hayano Tetsuo Nakajo 《Catalysis Today》2004,88(3-4):103-109
Activity for hydrolysis of CCl2F2 (CFC12) on various metal sulfate was investigated. Zr(SO4)2 was found to be the most active while FeSO4, Cr2(SO4)3, Al2(SO4)3, La2(SO4)3 and Ce2(SO4)3 had intermediate activity. MnSO4, CoSO4, and MgSO4 showed low activity and SrSO4, CaSO4, and BaSO4 had even less activity. The major carbon containing product was CO2 and small amount of CClF3 and CO were formed over several sulfates. The crystal structure of the sulfates was stable during decomposition of CCl2F2, and the conversion reached a steady state after initial decrease at 275 °C over Zr(SO4)2 catalyst. The concentration of surface hydroxyl was larger than that over AlPO4-based catalysts and a reaction mechanism similar to that over AlPO4-based catalysts was proposed. 相似文献
18.
19.
20.
采用浸渍-焙烧法制备了Fe/Ti O2-Al2O3、Fe/Ce O2-Al2O3复合催化剂,以H2O2作为氧化剂,对亚甲基蓝废水进行降解处理,考察了催化剂加入量、H2O2加入量、p H、温度以及初始浓度的变化等因素对处理效果的影响。结果表明:Fe/Ti O2-Al2O3的催化性能稍优于Fe/Ce O2-Al2O3,并且在p H=5,温度为65℃条件下,当催化剂加入量为0.15 g、H2O2加入量为15 m L、反应时间为60 min时降解率即可达到97%以上。 相似文献