改性聚酰亚胺膜用于甲醇/甲基叔丁基醚的渗透汽化分离

本文以己二酸对聚酰胺羧酸进行改性，制得改性聚酰亚胺膜，用于甲醇／甲基叔丁基醚的渗透汽化分离。研究了制膜液浓度、己二酸含量、原料液组成及温度等条件对膜分离性能的影响，并分析了膜的结构与特征基团的光谱图。     

渗透汽化膜处理低浓度甲醇废水的研究进展

由于石油资源短缺和我国新能源战略的进一步实施,甲醇被认为是石油替代品之一。随着甲醇需求量的增加,其生产过程中产生的含醇废水也急剧增加,由此造成低浓度甲醇废水污染日趋严重。渗透汽化膜分离技术被认为是治理低浓度甲醇废水的较好方法。简要介绍了渗透汽化膜处理低浓度甲醇废水的研究进展,并对其未来的研究趋势和发展前景进行了展望。     

甲醇／正己烷的渗透汽化分离的研究：I.渗透汽化膜的研制

本文研制了从甲醇／正己烷体系中分离甲醇的渗透汽化复合膜ＣＡ／ＰＡＮ（ＰＥＳ）、ＰＶＡ／ＰＡＮ（ＰＥＳ）。实验证明膜对该体系有较高的选择分离性和良好的渗透性，当进料甲醇浓度为３％时，渗透通量Ｊ≈０．６００ｋｇ／ｈ·ｍ＾２，分离因子α→∝。本文还考察了不同操作条件对膜分离性能的影响及膜的稳定性和均匀性。     

渗透汽化膜机理研究

用顺丁烯二酸酐对聚乙烯醇（ＰＶＡ）进行交联制得渗透汽化膜,并用于水－乙醇渗透汽化分离,研究了膜的溶胀平衡过程及选择溶解与渗透汽化关系,结果表明,膜对水优先溶解,其分离系数主要由溶解选择性控制,透过速率主要由溶胀度控制。     

CA和CTA膜分离MeOH/MTBE混合物渗透汽化性能研究

分别研究了甲醇(MeOH)和甲基叔丁基醚(MTBE)纯纽分在二醋酸纤维素(CA)和三醋酸纤维素(CTA)膜内的吸着性能、扩散系数及渗透通量.结果表明,活度在0.2～1.0范围内,MeOH在CA和CTA膜内的平衡吸着质量分数分别为0.018～0.172和0.032～0.175,远大于MTBE,而组分在2种膜中的溶解度无明显差别,2种组分在CTA膜中的扩散系数和渗透通量均大于CA膜.考察了进料温度在25℃、32℃和40℃下,料液中MeOH质量分数为5%～35%时,MeOH/MTBE混合物在CA膜中的渗透通量和分离系数,结果表明,随着进料温度和料液中MeOH浓度的升高,通量增加,分离系数减小.     

芳烃/脂肪烃渗透汽化分离膜的研究进展

芳烃/脂肪烃分离是石油化工中重要的分离过程,渗透汽化膜分离技术是现有高能耗芳烃/脂肪烃分离过程的潜在技术。以调整石脑油的芳烃含量,生产“低苯汽油”或低芳烃含量的优质乙烯裂解原料为背景,论述了芳烃/脂肪烃混合物的渗透汽化分离膜的研究进展。     

甲醇/正己烷的渗透汽化分离的研究 Ⅰ.渗透汽化膜的研制

本文研制了从甲醇／正己烷体系中分离甲醇的渗透汽化复合膜ＣＡ／ＰＡＮ（ＰＥＳ）、ＰＶＡ／ＰＡＮ（ＰＥＳ）。实验证明膜对该体系有较高的选择分离性和良好的渗透性，当进料甲醇浓度为３％时，渗透通量Ｊ≈０．６００ｋｇ／ｈ·ｍ２，分离因子α→∝。本文还考察了不同操作条件对膜分离性能的影响及膜的稳定性和均匀性。     

硅橡胶膜在渗透汽化分离中的应用及研究进展

综述了硅橡胶膜在渗透汽化分离(有机废水处理、生物发酵分离)中的应用及其制备技术(无机物填充改性、共缩聚或引入侧链基团改性)的最新研究进展.     

用于脱除C5及MTBE中甲醇的渗透汽化膜研究

Several pervaporation membranes, cellulose acetate (CA), polyvinylbutyral (PVB), poly(MMA-co-AA),MMA-AA-BA, CA/PVB blend and CA/poly(MMA-co-AA) blend, were prepared, and their pervaporation properties were evaluated by separation of methanol/C5 or methanol/MTBE (methyl tert-butyl ether). The results shows that the CA composite membrane has a high separation performance (flux Jmethanol = 350 g.m-2.h-1 and separation factor α＞400) for methanol/C5 mixtures, and the pervaporation characteristics of MMA-AA-BA copolymer membranes changes with the ratio of copolymer. For CA/poly(MMA-co-AA) blend membrane, the pervaporation performance is improved in comparison with CA or poly(MMA-co-AA) membrane. From the experiment of CA/PVB blend membranes for methanol/MTBE mixture, it is found that the compatibility of blends may affect the separation features of blend membrane.     

分离有机物水溶液的渗透汽化与汽化渗透膜

该文基于４５篇最新文献，较详细地论述了渗透汽化膜与汽化渗透膜的有机物水溶液分离性能及其影响因素，包括高聚物特征，料液浓度，温度，古游侧压力，膜厚度和操作时间，指出用多数高聚物膜进行渗透汽化操作可以有效地分离多数有机醇，酮，酸，酯，酰胺以及二Ｅ烷，乙腈，吡啶，二甲亚砜和四氢呋喃水溶液；而以壳聚糖及其衍生物膜进行汽化渗透操作则具有更高的分离系数。该文还简要介绍了渗透汽化膜的新应用。为渗透汽化与汽化渗透     

Pervaporation separation of methyl tert-butyl ether/methanol mixtures using a high-performance blended membrane

For the separation of methyl tert-butyl ether (MTBE) and methanol mixtures, we investigated the pervaporation performance of a blend membrane made from cellulose acetate and cellulose acetate hydrogen phthalate. At first the influence of the blend composition was studied with a certain feed mixture. We found that all the tested membranes permeate methanol preferentially. The selectivity increases and the permeation rate decreases with increasing cellulose acetate content in the blend. Therefore, an optimal blend composition of 30 wt % in cellulose acetate was chosen to evaluate the influence of the feed composition and the experimental temperature on the pervaporation performance. When the feed temperature or the methanol content in the feed increases, the permeation rates are greatly enhanced and the selectivity decreases. However, the temperature effect is more significant at low methanol content in the feed and becomes negligible at high methanol content in the feed where plasticity effects prevail. A comparison, carried out with all the membranes until now used for the separation of MTBE/methanol mixtures, showed that the blended membrane studied in this present work presents good permselective properties. © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 64: 875–882, 1997     

1-丁烯中微量甲基叔丁基醚和甲醇含量的测定方法改进

根据测定1-丁烯中微量甲基叔丁基醚和甲醇的分析方法中存在的问题,分别对进样方式、毛细管色谱柱和仪器操作条件作了改进,建立了一次进样便可同时检测甲基叔丁基醚和甲醇的气相色谱法。改进后的方法操作简便,分离效果及重复性良好。     

杂多酸催化合成甲基叔丁基醚的研究

介绍了以叔丁醇和甲醇为原料,在杂多酸催化下合成甲基叔丁基醚（ＭＴＢＥ）的方法,探索了反应温度、催化剂用量、反应摩尔比等诸因素对合成工艺、催化剂活性和选择性的影响,确定了适宜的工艺条件。     

Effect of compatibility of cellulose acetate/poly(vinyl butyral) blends on pervaporation behavior of their membranes for methanol/methyl tert‐butyl ether mixture

Binary blends and their blend membranes of cellulose acetate (CA) and poly(vinyl butyral) (PVB) are prepared by solution blending. The compatibility of the blends is studied by viscometry and Fourier transform IR. It is found that the incompatibility of the blends is markedly manifested when the weight fraction of PVB in the CA/PVB blends (W_PVB) is located at higher regions. On the other hand, compatibility is obtained for the CA/PVB blends with lower W_PVB values, especially at about 0.2. This compatibility is believed to play a key role in the good pervaporation behavior of CA/PVB blend membranes. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 2434–2439, 2002     

Separation of Azeotropic Dimethylcarbonate/Methanol Mixtures by Pervaporation: Sorption and Diffusion Behaviors in the Pure and Nano Silica Filled PDMS Membranes

In this article, polydimethylsiloxane and hydrophobic nano-silica filled polydimethylsiloxane membranes were prepared and employed in dimethylcarbonate (DMC) removal from the DMC/methanol mixture via pervaporation. The sorption and diffusion behavior of the binary molecule were discussed separately to provide qualitative estimation of the PV performance in both membranes. Compared with the polydimethylsiloxane membrane, hydrophobic nano-silica filled polydimethylsiloxane membranes had a little lower sorption selectivity but higher diffusion selectivity. In both membranes, the sorption value was obtained by both experimentation and model prediction. The Flory-Huggins model was performed to predict the solvent uptakes and the sorption concentrations based on the experimental results. The sorption behavior of DMC was predictable, while the methanol solubility was a little higher than the experimental results. Moreover, the diffusion behavior was studied by Fick's law, the calculated diffusion coefficients of the permeates demonstrated a diffusion-coupling phenomenon, especially in hydrophobic nano-silica filled polydimethylsiloxane membranes. Methanol molecules diffused faster than DMC, suggesting the low diffusion selectivity. The PV performance was affected by both sorption and diffusion. Sorption was demonstrated to be a decisive factor in this pervaporation process.     

渗透汽化膜分离MeOH/MTBE混合物的传质分析——单组分在膜中的扩散

用石英晶体微平衡法测定了298.15 K、305.75 K、312.95 K下MeOH（甲醇）和MTBE（甲基叔丁基醚）在CA（醋酸纤维素）膜中的吸着平衡数据和吸着动力学数据.结果表明：MeOH和MTBE在CA膜中的传质过程属于Fick扩散类型;MeOH在CA膜中的平衡吸着量和扩散系数都比MTBE大,说明CA膜对MeOH/MTBE混合物有较好的分离性能;同一吸着温度下,吸着速度和平衡吸着量均随着吸着蒸气压的升高而升高;可用Eyring的扩散“空穴”理论解释MeOH和MTBE在膜中的扩散行为.     

Use of Sodium Alginate-Poly(vinyl pyrrolidone) Membranes for Pervaporation Separation of Acetone/Water Mixtures

Pervaporative separation of acetone from water at a concentration range of 0–100 wt% were studied using sodium alginate (NaAlg)/Poly vinyl pyrrolidone (PVP) membranes. Membranes were prepared in different ratios (w/w) (100/0, 95/5, 90/10, 85/15, 80/20, 75/25) of NaAlg/PVP by crosslinking with CaCl₂. Experimental studies were carried out to investigate the effects of the operating temperature, feed composition, and membrane thickness on the pervaporation performance. The optimum operating temperature, membrane thickness, NaAlg/PVP ratio, and feed composition were determined as 40°C, 70 µm, 75/25 (w/w), and 20 wt% acetone, respectively. The effect of PVP content in the membranes was investigated on pervaporation performance. The permeation rate was increased with increasing the PVP content; however, there was no appreciable change about the separation factor. The permeation rate and separation factor values were found to be in the range of 0.304–1.023 kg/m² h and 16–57, respectively. In addition, the sorption-diffusion properties of the alginate membranes were investigated at the operating temperature and the feed composition. It was found that the sorption selectivity was the dominant factor for the separation of acetone/water mixtures.     

Adsorption Studies for the Removal of Methyl tert-Butyl Ether on Various Commercially Available GACs from an Aqueous Medium

This study highlights the potential of four commercially available granular-activated carbons (GACs) to remove Methyl tert-butyl ether (MTBE) from an aqueous medium. Thermodynamics and kinetics parameters were elucidated. The FT-IR spectra showed decrease in peak intensity after the adsorption. The decline in the peak intensity revealed that the adsorption occurred on available active sites over the surface of the GACs. The adsorption on GACs was maximum in the pH range 7–8, with maximum adsorption capacity (47.82 mg/g, pH 8) observed with CGAC. The contact time studies showed optimum adsorption of MTBE on CGAC (67.05 mg/g) at 300 mg/L initial MTBE concentration. The applicability of the Freundlich model illustrates a multilayer adsorption process. The adsorption process is endothermic in nature. The kinetics studies showed that the adsorption follows the pseudo-second-order model on GACs and the intraparticle diffusion is the rate-controlling mechanism on CGAC.     

甲基乙烯基醚/马来酸酐共聚物合成研究

以过氧化十二酰为引发剂(IN),采用溶液自由基共聚合方法,实现了甲基乙烯基醚(MVE)与马来酸酐(MAN)的交替共聚合。通过详细研究反应温度、引发剂用量、溶剂配比、溶剂用量及反应时间等因素对共聚物产率及产品特性粘度的影响,优化了制备甲基乙烯基醚/马来酸酐共聚物的工艺条件。最后通过FTIR和13CNMR表征了共聚物的结构。