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1.
酸处理Silicalite—Ⅰ沸石填充硅橡胶渗透蒸发分离膜   总被引:1,自引:1,他引:0  
研究酸处理Slilicalite-Ⅰ沸石对有机溶剂、水的吸附、脱附性质,酸处理Silicalite-Ⅰ填充硅橡胶对低浓度有机溶剂水溶液的渗透蒸发分离性能以及填充膜的力学性能。实验结果表明,在硅橡胶胶膜中填充酸处理Silicalite-Ⅰ沸石能改善膜对有机溶剂-水混合物的分离性能,且分离性能的改善与沸石在膜中的填充量以及硅橡胶的品种有关。另外,沸石的填充也有利于改善膜的力学性能。  相似文献   

2.
研究了粒径为15μm和5μm的水热处理Silicalite-I填充PDMS膜以及酸处理Silicalite-I填充不同品种硅像胶膜对低浓度乙醇-水混合物的渗透发分离性能的影响。结果表明,沸石粒径的减小,不利于乙醇-水分离系数的提高;不同品种硅橡胶有沸石充膜对乙醇-水的渗透蒸发分离性能与硅橡胶本身的性质有关。  相似文献   

3.
研究了粒径为15μm和5μm的水热处理Silicalite-Ⅰ填充PDMS膜以及酸处理Silicalite-Ⅰ填充不同品种硅橡胶膜对低浓度乙醇-水混合物的渗透蒸发分离性能的影响。结果表明,沸石粒径的减小,不利于乙醇-水分离系数的提高;不同品种硅橡胶的沸石填充膜对乙醇-水的渗透蒸发分离性能与硅橡胶本身的性质有关。  相似文献   

4.
研究水热处理Silicalite—Ⅰ沸石对乙醇和水的吸附、脱附性质以及其填充PDMS膜对乙醇、水的渗透蒸发通量和对低浓度有机溶剂一水混合物的渗透蒸发分离性能。实验结果表明,Silicalite—Ⅰ沸石经水热处理,其水吸附量大为减少,因此其填充PDMS膜对有机溶剂-水混合物,主要是醇-水混合物的分离系数有显著提高。  相似文献   

5.
研究Silicalite-I填充PDMS膜对乙醇和水的吸附、脱附和渗透蒸发性质以及吸附膜中丙酮在DSC测试中的行为。结果表明,沸石填充膜对乙醇的吸附量和渗透蒸发通量均明显高于水,且乙醇的沸石填充膜中达到吸附、脱附平衡的速度均快于水;且吸附在填充和不填充沸石的硅橡胶膜中丙酮的熔融温度有明显的提高,说明硅橡胶膜与有机溶剂有较强的相互作用。此外,沸石填充膜的结构在30wt%填充量附近有一改变,表明膜中硅  相似文献   

6.
陈新  龙英才 《应用化学》1994,11(3):21-25
Silicalite-I沸石经过酸处理或水热处理可完善其晶体结构,提高对乙醇的吸附选择性,由此提高对乙醇-水混合物的分离系数,特别是先经过酸处理再经过水解处理的Silicalite-Ⅱ沸石填充聚二甲基硅氧烷橡胶膜,乙醇-水的分离系数可达30左右。  相似文献   

7.
Silicalite-Ⅰ沸石经过酸处理或水热处理可完善其晶体结构,提高对乙醇的吸附选择性,由此提高对乙醇-水混合物的分离系数。特别是先经过酸处理再经过水热处理的Silicalite-Ⅰ沸石填充聚二甲基硅氧烷橡胶膜(PDMS橡胶膜),乙醇-水的分离系数可达30左右。  相似文献   

8.
研究Silicalite-Ⅰ填充PDMS膜对乙醇和水的吸附、脱附和渗透蒸发性质以及吸附膜中丙酮在DSC测试中的行为。结果表明,沸石填充膜对乙醇的吸附量和渗透蒸发通量均明显高于水,且乙醇在沸石填充膜中达到吸附、脱附平衡的速度均快于水;且吸附在填充和不填充沸石的硅橡胶膜中丙酮的熔融温度有明显的提高,说明硅橡胶膜与有机溶剂有较强的相互作用。此外,沸石填充膜的结构在30wt%填充量附近有一改变,表明膜中硅橡胶的连续性遭到破坏。  相似文献   

9.
李贤森  项寿鹤 《催化学报》2000,21(5):475-478
探索了如何在过滤陶瓷片上制备Silicalite-l和β沸石分子筛复合膜,对它们分离水中微量苯酚和苯的性能进行了考察,并用XRD,SEM和UV等测试方法对其物理化学性能和结构进行了表征,结果表明:Silicalite-l分子筛膜,两者的平均脱除率分别为69.9%和51.5%,通过对Silicalite-l沸石分子筛复合膜进行二次合成及高温水蒸气处理,可在很大程度上改善其了性能。  相似文献   

10.
在丙烷芳构化反应中,氢气起着相当重要的作用;根据理论分析,消除氢气将会有利于芳构化反应的进行。在Silicalite-1沸石分子筛膜反应器,丙烷芳构化反应中的芳烃选择性提高了10%-20%。针Silicalite-l膜反应器与氧化铝膜反应器中的反应结果相比较,表明膜反应器效果不仅取决于膜的渗透选择性,而且还取决于膜的渗透率。  相似文献   

11.
新型含钴硅橡胶离聚体膜的富氧性能   总被引:3,自引:0,他引:3  
硅橡胶 ( PDMS)是最早使用的气体分离膜材料 ,其氧透过系数较高 ( PO2 =6 0 0 Barrer) ,但氧氮分离系数低 ( αO2 /N2 =2 .0 ) ,成膜性及膜强度差 ,因而限制了其应用 .PDMS改性一直是气体分离膜研究的重要课题[1] ,提高氧氮分离性 ,改善成膜性 ,而不影响其透气性 ,成为人们追求  相似文献   

12.
以十三氟辛基三乙氧基硅烷、四甲基二乙烯硅氧烷、乙烯基三甲氧基硅烷和正硅酸乙酯为原料,通过水解缩合制备了乙烯基含氟硅树脂。乙烯基硅橡胶和乙烯基含氟硅树脂为基质材料,含氢硅油为交联剂,硅氢加成制备了改性硅橡胶杂化膜材料。透气性能测试表明,当含氟硅树脂质量分数50.0%时,膜的成膜性和富氧性能之间达到最佳平衡点,30℃和0.01 MPa压差下,P(O2)为628 Barre,a(O2/N2)为3.36。与普通乙烯基硅橡胶交联膜比,这种有机―无机杂化膜在保持原有氧气透过系数的基础上,较好的改进了氧氮分离性能。  相似文献   

13.
高硅ZSM—5沸石填充硅橡胶膜的醇—水渗透蒸发分离性质   总被引:5,自引:3,他引:5  
高硅ZSM-5沸石填充疏水性硅橡胶蓦地低浓度醇-水体度醇-水体的渗透蒸发性质的研究有明,提高沸石硅铝比,增加填充量以及进行酸处理皆有利于改善膜对醇-水的分离系数和通量。料液的成,浓度以及温度对膜的分离性质也有显著影响。  相似文献   

14.
研究了沸石的处理方式、渗透蒸发体系的组成以及醇-水混合物中氢键的变化对Silicalite-I沸石填充聚二甲基硅橡胶膜渗透蒸发性质的影响.实验结果表明,沸石经水热处理以及在醇-水混合物中加入盐、酸等电解质能提高膜对醇-水混合物的分离性能.  相似文献   

15.
New hydrophobic poly(phthalazinone ether sulfone ketone) (PPESK) hollow fiber composite membranes coated with silicone rubber and with sol–gel polytrifluoropropylsiloxane were obtained by surface-coated modification method. The effects of coating time, coating temperature and the concentration of silicone rubber solution on the vacuum membrane distillation (VMD) properties of silicone rubber coated membranes were investigated. It was found that high water permeate flux could be gotten in low temperature and low concentration of silicone rubber solution. When the coating temperature is 60 °C, the coating time is 9 h and the concentration of silicone rubber solution is 5 g L−1 the water permeate flux of the silicone rubber coated membrane is 3.5 L m−2 h−1. The prepolymerization time influence the performance of polytrifluoropropylsiloxane coated membranes, and higher prepolymerization time decrease the water permeate flux of the membrane. The water permeate flux and the salt rejection was 3.7 L m−2 h−1 and 94.6%, respectively in 30 min prepolymerization period. The VMD performances of two composite membranes during long-term operation were studied, and the results indicated that the VMD performances of two composite membranes are quite stable. The salt rejection of silicone rubber coated membrane decreased from 99 to 95% and the water permeate flux fluctuated between 2.0 and 2.5 L m−2 h−1. The salt rejection of polytrifluoropropylsiloxane coated membrane decreased from 98 to 94% and the water permeate flux fluctuated in 1 L m−2 h−1 range.  相似文献   

16.
Photo‐oxidative degradation of treated and untreated nano CaCO3: silicone rubber composite was studied under accelerated UV irradiation (≥290 nm) at different time intervals. Prolonged exposure to UV leads to a progressive decrease in mechanical and physical properties along with the change in behavior of filler‐matrix interaction. This was due to decrease in cross‐linking density with increase in mobility of rubber chains. Meanwhile, synthesized nano CaCO3 was modified with stearic acid for uniform dispersion in rubber matrix. The increase in carbonyl (>CO), hydroxyl (? OH), CO2, and alkene functional groups on the UV exposed surface of treated and untreated nano CaCO3: silicone rubber composites at different time intervals was studied using Fourier transform infrared (FTIR) spectroscopy. The change in morphological behavior of filler‐matrix interaction after UV exposure was studied using SEM. Overall, the study showed that the treated nano CaCO3: silicone composites were affected more by UV exposure than untreated nano CaCO3: silicone composites and pristine composite after UV exposure. This effect was due to peeling of stearic acid from the surface of CaCO3, which makes the rubber chains slippery and thus separation of filler and rubber chains takes place with initiation of fast‐degradation. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   

17.
Bi-injection moulding is a widely used process to manufacture engineering products and consumer goods. Typically, a thermoplastic is combined with rubber or another thermoplastic to create colour differences or hard and soft areas, respectively. The aim of this study was to optimise the injection parameters and processing conditions for the moulding of two-component standard peel test specimens with suitable functional properties. In this work, all parameters of thermo-rheo-kinetic behaviour were identified to predict the entire filling stage and the effect of a liquid silicone rubber cross-linking reaction during the injection moulding process. The models of Carreau-Yasuda and Isayev-Deng regarding the thermal dependence assumed by Arrhenius’ law were used. In our study, over-injection moulding is simulated and examined using finite element software (Cadmould 3D) to investigate the thermo-rheo-kinetic behaviour and the adhesion of liquid silicone rubber during the filling mould process in over-moulding. Numerical simulation results were then compared with the experimental results, and good agreement was obtained.  相似文献   

18.
Ben-Yaakov S  Ruth E 《Talanta》1980,27(5):391-395
A method for reducing the flow-sensitivity of polarographic dissolved-oxygen sensors has been modelled mathematically and tested experimentally. The improved probe uses a two-layer membrane: the first layer is made of Teflon and the second of silicone rubber, which is more permeable than Teflon to oxygen. This arrangement reduces the flow-sensitivity to about 4% of that for a single-membrane 1-mil Teflon; second membrane 2.5-mil silicone rubber. (b) First membrane 0.5-mil Teflon; second membrane 5-mil silicone rubber.  相似文献   

19.
Triboelectric nanogenerator (TENG) technologies have explosive development in the field of energy harvesting and self-powered sensing. As the key element of triboelectric devices, dielectric polymers have obtained much attention in recent years. The dielectric properties of polymer determine the output performance of TENG. In this paper, we take silicone rubber as an example of dielectric polymers, to study the properties of molecular structure influence on the dielectric properties and mechanical properties by the molecular dynamics simulation method. The free volume fraction, dielectric constant, and mechanical properties of silicone rubbers with different branch chains were calculated. The dielectric constant is highly related to the free volume distribution and the dipole moments of silicone rubbers with different amounts of branch chains. For fewer branch chains silicone rubber, the free volume distribution contributes most to the dielectric constant; for more branch chains silicone rubber, the dipole moment dominates the dielectric constant. Therefore, the silicone rubber ratio has a great influence on the dielectric constant of silicone rubber. With the increase of temperature, the dielectric constant of 2-chain silicone rubber increases at first and then decreases, and the maximum value is obtained near 300 K. Therefore, it is necessary to control the temperature when silicone rubber is used as a dielectric material. This work can be a guide for improving the dielectric properties of silicone rubber, and it provides a new approach to the optimal design of high-performance triboelectric nanogenerators.  相似文献   

20.
<正> 我们研制了一种硅氢加成型室温固化硅橡胶,这种橡胶不但有较好的力学性能,而且与各类材料如金属、塑料、陶瓷、玻璃等都有很好的粘结力,是一种具有弹性的胶粘剂。该胶粘剂是利用一种含乙烯基聚硅氧烷、含氢聚硅氧烷以及二氧化硅补强剂在铂催化剂  相似文献   

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