Synthesis of Methyl tert-Butyl Ether from tert-Butyl Alcohol and Methanol Using Beta Zeolite Catalysts

MTBE synthesis from tert-butyl alcohol (t-BA) and methanol has been studied using beta zeolites. Increasing the reaction temperature results in an increase of t-BA conversion with concomittant decrease of MTBE selectivity. The t-BA conversion decreases with increasing calcination temperature and alkali metal ion exchange of H zeolite. The catalytic results are correlated with the surface area and the acidity of catalysts.     

渗透汽化分离芳烃/烷烃混合体系的研究进展*

本文对近年来应用于分离芳香烃/ 烷烃混合体系的渗透汽化(简称PV ) 膜材料, 特别是高分子材料进行了较为系统的综述, 并简要概述了渗透汽化膜分离特点、机制以及影响渗透汽化分离过程的主要因素。     

Electrotreatment of Wastewaters from High-Octane Fuel Production To Remove Methyl tert-Butyl Ether and Methanol

The possibility is examined of removing methyl tert-butyl ether from wastewaters by electrotreatment.     

Production of Highly Pure Methyl tert-Butyl Ether

Russian Journal of Applied Chemistry - The batch processing of an organic solvent methyl tert-butyl ether with obtaining a product of high purity was investigated. The separation coefficients of...     

Study of the Surface Tensions of Binary Mixtures of Isomeric Chlorobutanes with Methyl tert-Butyl Ether

In the present work we report experimental surface tensions for binary mixtures of isomeric chlorobutanes with methyl tert-butyl ether from 283.15 to 303.15 K, measured with a drop volume tensiometer. From these experimental data the corresponding surface tension deviations were calculated and correlated using a Redlich-Kister type polynomial. Finally, we include the calculation of excess surface compositions for all of the mixtures from 288.15 K to 308.15 K.     

无铅汽油样品中甲基-叔丁基醚的定量测定

1　引　　言由于含铅汽油给环境带来的不利影响 ,近几年来 ,无铅汽油已开始在我国大范围使用。甲基叔丁基醚 (ｍｅｔｈｙｌｔｅｒｔ ｂｕｔｙｌｅｔｈｅｒ,ＭＴＢＥ)是无铅汽油中的一种常用添加剂 ,可提高辛烷值使汽油燃烧更完全 ,从而减少环境污染。但是 ,ＭＴＢＥ的使用在许多发达国家特别是美国引起了很大争议。这是因为ＭＴＢＥ在自然条件下很难降解 ,在水中的溶解度较高(42 0 0 0ｍｇ/Ｌ) ,由于地下储油罐泄露和汽车尾气的排放 ,环境中尤其是地下水中ＭＴＢＥ的含量正在迅速增加。同时 ,研究发现ＭＴＢＥ存在潜在的致瘤性 ,可破坏小鼠…     

渗透汽化芳烃/烷烃分离膜材料

芳烃/烷烃混合物的分离在石油化工及环保领域都具有重大意义.与传统的萃取精馏等技术相比,渗透汽化膜技术以其清洁、节能和高效的优点,应用于芳烃/烷烃混合物的分离并受到重视.本文综述了渗透汽化芳烃/烷烃分离膜的研究进展,概述了渗透汽化技术的基本原理和应用,重点介绍了用于渗透汽化芳烃/烷烃分离的聚酰亚胺、聚氨酯等高分子膜材料的结构特点和分离性能.总结了膜材料的接枝、共聚和共混,添加传质促进剂的改性方法.分析了渗透汽化芳烃,烷烃分离膜材料的研究思路,在此基础上对渗透汽化芳烃/烷烃分离膜材料的研究方向和发展前景进行了展望.     

轻质烃类中微量甲醇、甲基叔丁基醚等含氧化合物的测定

在乙烯厂生产中微量含氧化合物的测定非常重要,含氧化合物的存在可引起催化剂中毒,致使生产不能长周期运行。对乙烯、丁烯-1中含氧化合物的测定已有报道。但随着仪器和数据处理设备的更新有些缺陷就显现出来。近年来,毛细管色谱柱在含氧化合物的测定上也得到应用,但所使用的极性柱对甲醇、甲基叔丁基醚（MTBE）等含氧化合物分析时常有C3,C4和C5等烃类的干扰,在分析实际样品时会有合峰出现,无法得到准确结果。本文采用超强极性的LOWOX色谱柱,可以排除轻质烃类的干扰,降低检出限。     

PAHs Formation in the Depositions in a Methyl tert-Butyl Ether/Ar,a Methyl tert-Butyl Ether/O2/Ar and a Methyl tert-Butyl Ether/H2/Ar RF Plasma Environment

Contents and distributions of polycyclic aromatic hydrocarbons (PAHs) in the depositions were investigated and discussed in a MTBE/Ar, a MTBE/O₂/Ar and a MTBE/H₂/Ar plasma systems. A radio-frequency (RF) plasma system was used to produce the depositions under the designed operational condition. The identification and quantification of PAHs was accomplished by using a GC with a mass selectivity detector (GC/MS). Results indicated that when the input power controlled at high wattage (70 W) in the three systems, the contents of total-PAH in the MTBE/Ar system are higher than those of total-PAH in other system with adding O₂ or H₂. The comparison of three systems indicated the formation and accumulation of PAHs in the MTBE/Ar system is easier than other systems. At high input power wattage, when the MTBE/Ar mixture added O₂ or H₂, the domain pattern was shifted from both 3- and 4-ring PAH to 2-ring PAH. As far as the total-PAH content is concerned, the MTBE/Ar system at 70 W was found to have the highest mean total-PAH content (1540 g/g), while the MTBE/O₂/Ar system at 20 W had the lowest mean total-PAH content (44.4 g/g).     

合成甲基叔丁基醚的分子筛催化剂研究

通过对ＨＺＳＭ－５,ＨＺＲＰ－１和Ｈβ三种类型分子筛催化剂上合成甲基叔丁基醚的活性测定和结构表征,初步考察了分子筛孔结构对催化活性的影响。在此基础上,对适宜孔结构的分子筛进行了水热改性,考察了改性条件对分子筛催化剂的性质及其合成甲基叔丁基醚反应催化活性的影响,得到了催化活性较好的分子筛催化剂。     

聚苯基喹噁啉膜对有机液体混合物的渗透气化性能

研究了聚苯基喹噁啉[PPQ(B)]及聚苯基单醚喹噁啉[PPQ(E)]膜对水/乙醇、水/异丙醇、甲苯/乙醇和苯/环已烷等液体混合物体系的渗透气化特性。发现PPQ(B)、PPQ(E)膜水/乙醇及水/异丙醇混合物而言,均属水优先透过型。PPQ(E)膜在70℃下,对水/异丙醇(6.3/93.7wt%)混合液的分离系数α_(w/p)达127。实验结果还表明,PPQ(B)膜对甲苯/乙醇及苯/环已烷混合液的渗透气化分别为甲苯及苯优先透过型。对以上实验结果从理论上进行了探讨。     

Synthesis of Fullerene-Polyphenylene Oxide Membranes for Separating Aqueous-Organic Mixtures

Homogeneous fullerene-polyphenylene oxide membranes containing up to 2 wt % C₆₀ are synthesized and characterized by the density, electrical resistivity, and contact angle with water and ethanol. The effect of fullerene additive on the transport characteristics of the membranes in pervaporation of water mixtures with ethanol and ethyl acetate is studied.     

Activity of Polymeric and Zeolite-Containing Catalysts in Production of Methyl tert-Butyl Ether

The effect of structural and acid characteristics of catalysts of various nature (sulfonic cation exchangers of the KU-23 type and high-silica zeolite of the ZSM-5 type) on their activity and selectivity in production of methyl tert-butyl ether from isobutylene and methanol was studied.     

毛细管气相色谱法分析清洁汽油中甲基叔丁基醚含量

1 引 言为了提高汽油的辛烷值及抗爆性能,甲基叔丁基醚(MTBE)可作为一种重要的调和组分。但由于其对健康的不良影响，其含量应严格地进行控制。以往气相色谱法中较准确的内标法，由于对相对校正因子的计算不准确而使定量的准确度较差，低含量时结果偏高。因而开发一种更准确的分析方法势在必行。2 实验部分2.1 仪器与试剂 HP6890plus型气相色谱仪及具程序升温功能的其它型号的气相色谱仪均可,具一个十通切换阀、FID检测器、HP6890化学工作站。极性预分离柱:0.56 m×0.35 mm i.d 内填充为20%(m/m)TCEP/Chromosorb 0.1　mm;非极性分离…     

磺化聚砜醇水分离膜的研究

磺化聚砜是一种性能优异的离子交换膜材料,本文采用磺化反应合成了一系列不同离子交换容量(IEC)的磺化聚砜,研究了磺化聚砜膜的离子交换容量与醇水分离性能的关系,考察了用不同碱金属碱中和后膜分离性能的变化规律,结果表明:随着离子交换容量的增大,渗透通量增大,而分离因子在IEC=1.0meq/g左右出现最大值。不同碱金属离子膜的渗透通量按下列次序递减:L_i~+>Na~+>K~+,分离因子变化次序刚好相反。此外,料液温度,料液浓度对膜的醇水分离性能有较大的影响。     

Maleic Anhydride Crosslinked Alginate-Chitosan Blend Membranes for Pervaporation of Ethylene Glycol-Water Mixtures

Calcium alginate-chitosan (CA/CS) blended membranes were prepared and crosslinked with maleic anhydride (MA) for the pervaporation (PV) separation of ethylene glycol (EG)/water mixtures at 30°C. The structure and properties of blend membranes were studied with the aid of FTIR, XRD, TGA, and SEM. The effect of experimental parameters such as feed composition, membrane thickness, and permeate pressure on separation performance of the MA crosslinked membranes were determined in terms of flux, selectivity, and pervaporation separation index. Sorption studies were carried out to evaluate the extent of interaction and degree of swelling of the blend membranes in pure, as well as in binary mixtures. The experimental results suggested that the crosslinked membrane (M-CA/CS) exhibited a good selectivity of 302 at a normalized flux of 0.38 kg.m^{? 2}.h^{? 1}.10 μ m at 30°C for 96.88 wt% EG aqueous solution.     

Excess Enthalpies of (2,2,4-Trimethylpentane or Cyclohexane) + Methyl tert-Butyl Ether + tert-Amyl Methyl Ether at 25°C

Microcalormetric measurements of excess molar enthalpies at 25°C are reported for two ternary mixtures 2,2,4-trimethylpentane + methyltert-butyl ether +tert-amyl methyl ether and cyclohexane + methyltert-butyl ether +tert-amyl methyl ether. Smooth representations of the results are presented and used to construct constant-enthalpy contours on Roozeboom diagrams. Comparisons of the experimental results with estimates based on the Flory theory of mixtures are also described.     

聚电解质渗透汽化膜

介绍了聚电解质渗透汽化膜的研究进展，包括聚电解质以及聚电解质复合物的定义、特点、制备、着重介绍了近年来开发的一些重要的聚电解质渗透汽化膜的制备方法及其分离性能。     

Determination of Trace of Methyl tert-Butyl Ether in Water Using Liquid Drop Headspace Sampling and GC

The possibility of applying headspace microextraction into a single drop of solvent for the determination of methyl tert -butyl ether in aqueous solutions has been demonstrated. A drop of benzyl alcohol is used for extraction. The analyte is extracted by suspending a 1.8 μL extracting drop directly from the tip of a microsyringe fixed above an extraction vial with a septum such that the needle passes through the septum and the needle tip is positioned above the surface of the solution. After the extraction is finished, the drop is retracted back into the needle and injected directly into a GC column. Optimization of experimental variables (time, temperature, stirring rate and ionic strength of the solution) with respect to the extraction efficiency was investigated. The calibration range for methyl tert-butyl ether was 0.01–10 ppm and the detection limit 7 ppb. The relative standard deviation for 0.1 ppm methyl tert -butyl ether in water was 5.5%.     

A Sensitive Method for Methyl tert-Butyl Ether Analysis in Water Samples by a New HS-SPME Vial and GC

In this study, a new sample vial has been designed for the extraction and determination of methyl tert-butyl ether (MTBE) in water samples by headspace solid-phase microextraction method. The special feature of this new vial is cooling the HS above the aqueous sample by cold water stream for maximum analyte absorption on SPME fiber coating. The analysis was by a gas chromatograph equipped with flame ionization detector and a capillary column (CP-sil 13 CB). Some significant variables affecting the extraction procedure were optimized. By use of divinylbenzene/carboxen/polydimethylsiloxane fiber, a sample volume of 10 mL, stirring rate of 1,000 rpm, salt concentration of 24%, extraction time of 15 min and extraction temperature of 83 °C, detection limit of 0.022 μg L⁻¹ and a good linearity (R ² = 0.998) in a calibration range of 0.1–400 μg L⁻¹ were achieved. The relative standard deviation for triplicate runs ranged between 6 and 8%. The method could be applied to the analysis of trace levels of MTBE in various water samples.