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REMOVAL OF CHROMATE ION FROM CONTAMINATED SYNTHETIC WATER USING MCM-41/ZSM-5 COMPOSITE
H. Kazemian, M. H. Mallah
Iranian Journal of Environmental Health Science & Engineering , 2008,
Abstract: In the present study removal of chromate anion (CrO42-) from a synthetic aqueous solution by a synthesized MCM-41/ZSM-5 composite and its modified form with the anionic surfactant of hexadecyl-teri methyl ammonium bromide; (surfactant modified composite) was investigated. According to the data obtained from batch test of MCM-41/ZSM-5 composite and surfactant modified composite, it is obvious that modification of the composite with anionic surfactant improves its affinity toward the oxyanion (917mL/g for MCM-41/ZSM-5 composite in comparison to 1870mL/g for surfactant modified composite). It was concluded that sorption capacity and selectivity of the composite will be remarkly improve toward chromate anion by modification of its surface by a surfactant; therefore surfactant modified composite is a suitable candidate for removal of chromate anion from contaminated solutions.
碱处理浓度对预脱铝zsm-5成孔过程及其mtg反应性能的影响  [PDF]
常江伟?,付廷俊?,张洪建?,周浩?,李忠?
无机化学学报 , 2015,
Abstract: 在80℃水浴条件下,对zsm-5分子筛进行酸碱处理改性;重点考察了碱处理溶液浓度对酸预处理脱铝后zsm-5分子筛微观结构及其催化甲醇制汽油(mtg)性能的影响。通过bet、xrd、ft-ir、nh3-tpd和tem等手段对样品进行表征。结果表明,单独酸处理没有改变分子筛孔结构,单独碱处理产生了并不明显的介孔。酸预处理后再碱处理可促进介孔的产生,产生更为显著的介孔结构;而且随着碱处理强度的增加,分子筛样品的介孔/微孔比表面积比例和孔体积均先增大后降低。酸浓度2mol·l-1,碱浓度0.4mol·l-1条件处理得到的分子筛,介孔比表面积比例和孔容均达到最大,酸量和酸强度最低。在400℃,0.1mpa,whsv=2.1h-1条件下,甲醇制汽油反应性能最佳:汽油收率由未改性时的30wt%提高到34wt%,寿命更是由16h延长到135h,芳烃含量由原来的73wt%降至20wt%。
Synthesis of MCM-48/ZSM-5 Composite Molecular Sieve by Two-step Crystallization
ZHOU Zhi-Hua,LU Jin-Ming,WU Shu-Feng,ZHOU Jing-Lin,WANG Jin-Qu
无机材料学报 , 2009, DOI: 10.3724/sp.j.1077.2009.00325
Abstract: Composite micro/mesoporous MCM-48/ZSM-5 materials were successfully prepared by using a twoa2step synthesis route. The different structures of composite materials compared with the mechanical mixture were characterized by powder XRD£ IR spectroscope£ SEM£ TEM£ N2 adsorption and the influence of the crystallization time was investigated. The results show that the composite MCM-48/ZSM-5 materials possess mesoporous wall constructed by secondary building units characteristic of ZSM-5 and threea2dimensional pore structure with pore size of about 2.6nm. The mesoporous framework of MCM-48/ZSM-5 is still found to be somewhat preserved after treatment in boiling water for 6h. It is proved that the selfa2assemble is a competitive process and the ratio of mesopore to micropore has a close relationship with crystallization time. The optimum crystallization time under 150 s 8h.
Oxidation of benzylic alcohols over Cr (MCM-41/ZSM-5) assisted by microwaves
Zoubida Lounis,Naouel Boumesla,A. E. K. Bengueddach
Applied Petrochemical Research , 2012, DOI: 10.1007/s13203-012-0007-5
Abstract: The oxidation of benzylic alcohols in the machine of microwave (Discover, CEM-SP1245 model, USA) by the composite material type Cr-(MCM41/ZSM5) with high crystallinity, exchanged at low content of chromium has dramatically reduced the reaction times and have high conversion rates and high yields compared to conventional heating. Ketones were obtained for only 10 min of reaction. The composite materials used containing both micropore and mesopore structures are stable for this type of reaction. The method uses composite materials Cr (50-MCM41/ZSM5) as the catalyst system and t-BuOOH as the stoichiometric terminal oxidant. The reactions carried out by the microwave and made without the use of an organic solvent, because, the substrates are mixed directly or, in our case, the subtract is mixed with silica which is inactive in the reaction.
混合胺体系中MCM-49/ZSM-35复合分子筛的晶化过程  [PDF]
徐龙伢,谢素娟
催化学报 , 2010, DOI: 10.3724/SP.J.1088.2010.00510
Abstract: ?采用X射线衍射、N2吸附-脱附、扫描电镜和傅里叶变换红外光谱等技术,研究了MCM-49/ZSM-35复合分子筛在Na2O-SiO2-Al2O3-CHA(环己胺)-HMI(六亚甲基亚胺)-H2O合成体系中,先在低温80?C老化4h,再经160?C晶化不同时间的演变过程.结果表明,在该混合胺体系中,首先生成MCM-49分子筛,随着晶化时间的延长,形成ZSM-35含量逐渐增加的MCM-49/ZSM-35复合分子筛,最后生成纯ZSM-35分子筛;ZSM-35的生成是以MCM-49分子筛的消耗为代价的.
Influence of ZSM-5(38)/Al-MCM-41 composite molecular sieve catalysts on pyrolysis of cellulose
ZSM-5(38)/Al-MCM-41复合分子筛对纤维素催化热解的影响

Xiaojuan Liu,Fengwen Yu,Yong Nie,Yao Luo,Jianbing Ji,
刘小娟
,于凤文,聂勇,罗瑶,计建炳

生物工程学报 , 2011,
Abstract: Pyrolysis of cellulose with different catalysts has been conducted in a fixed-bed reactor. Micro-mesoporous composite molecular sieves of ZSM-5(38)/Al-MCM-41 with different Si/Al ratios were prepared under hydrothermal conditions. With powder X-ray diffraction (XRD), the catalyst samples were characterized. GC-MS was used to analyze the bio-oil composition. The effects of catalysts on the pyrolysis product yields were investigated and the results were compared with the results of experiments performed without catalyst under the same pyrolitic conditions. The presence of the catalysts decreased the liquid yield, while increased the moisture content. The major improvement in the quality of bio-oil with the use of catalysts was the increase of DL-2,3-Butanediol. ZSM-5(38)/Al-MCM-41(20) favored the formation of phenol and 2-methoxy-phenol. In addition, these catalysts were all benefit for the generation of small molecular compounds. Also, it was found that ZSM-5(38) was better for the production of C4?C5 compounds. And micro-mesoporous composite molecular sieves mainly promoted the production of C6?C8 compounds.
zsm-5/mcm-41复合分子筛的合成与表征  [PDF]
张君涛,郝娜娜,王妮
燃料化学学报 , 2013,
Abstract: ?以碱处理的zsm-5浆液为硅铝源,通过水热自组装过程合成了介孔-微孔复合孔道结构的分子筛,并采用xrd、bet、hrtem、py-ir和水热处理等手段对合成分子筛进行了表征。结果表明,碱处理zsm-5时的苛刻程度是影响复合分子筛合成的重要因素,适宜的碱处理条件为naoh浓度1mol/l、80℃时处理1h。表征结果表明,复合分子筛具有规整互通的微孔-介孔梯级复合孔道结构,孔容、比表面积和平均孔径分别为0.63ml/g,684m2/g和3.76nm,属典型的mcm-41结构;与mcm-41相比,复合分子筛的b酸(尤其是强b酸)酸量明显增强,水热稳定性显著提高。
SYNTHESIS OF MCM-41/ZSM-3 COMPOSITE MOLECULAR SIEVES BY PRE-LAYING CRYSTAL-SEED
预置晶种合成MCM-41/ZSM-3复合分子筛

马广伟,葛学贵,黄少云,许中强
燃料化学学报 , 2003,
Abstract: 以十六烷基三甲基溴化铵和四甲基氢氧化铵为模板剂,以ZSM—3为晶种,在水热条件下合成了同时具有中孔和微孔的复合分子筛MCM—41/ZSM—3。通过XRD、IR、N2吸附脱附等温线和SEM表征,样品的XRD图谱在小角度衍射区和大角度衍射区同时出现了MCM—41和ZSM—3的衍射峰;IR图谱上也同时出现了MCM—41和ZSM-3的吸收谱带,并且合成样品与两种分子筛的机械混合物有明显差别;心吸附脱附等温线证明样品含中孔和微孔结构,并且微孔直径集中分布在0.7nm左右,中孔直径集中分布在3.3nm左右;从SEM照片可以看出,复合分子筛和机械混合物形貌不同,前者为附晶生长或再结晶,后者为均匀分散。
以十六烷基三甲基溴化铵为模板剂合成mcm-41/zsm-5复合分子筛的研究  [PDF]
陈艳红|,李春义|,杨朝合
燃料化学学报 , 2011,
Abstract: ?采用阳离子表面活性剂十六烷基三甲基溴化铵(ctab)为模板剂、以zsm-5为晶种,在水热晶化条件下合成了同时具有微孔和介孔的mcm-41/zsm-5复合分子筛;并考察了陈化温度、陈化时间、晶化时间及模板剂用量等条件对合成复合分子筛的影响。通过x射线衍射、扫描电镜、高分辨率透射电镜、红外光谱及n2静态吸附法等手段对合成样品进行表征,并与机械混合样品以及纯的zsm-5和mcmc-41进行比较。结果表明,所合成的样品同时具备微孔zsm-5和介孔mcm-41结构且在结构上不同于机械混合样品。
zsm-5(38)/al-mcm-41复合分子筛对纤维素催化热解的影响  [PDF]
刘小娟?,于凤文?,聂勇?,罗瑶?,计建炳?
生物工程学报 , 2011,
Abstract: 以纤维素为原料,以自制的不同硅铝比zsm-5(38)/al-mcm-41微-介孔复合分子筛为催化剂,在固定床反应器上进行了催化热解实验。采用xrd表征分子筛,采用gc-ms分析生物油成分,考查了催化剂的改变对生物质热解产物及生物油成分的影响。实验结果表明:添加催化剂后,生物油产率降低,且其含水率也有所增加。与未添加催化剂相比,生物油中dl-2,3-丁二醇有明显提高。其中,zsm-5(38)/al-mcm-41(20)最有利于苯酚、愈创木酚(2-甲氧基-苯酚)的生成。此外,这几种催化剂均有利于小分子化合物的生成,其中,zsm-5(38)有利于c4~c5化合物的生成,微-介孔复合分子筛则有利于c6~c8化合物的生成。
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