Abstract

In this study, we communicate our initial findings regarding the development of novel inorganic composite clinoptilolite membranes. The membranes were formed from natural clinoptilolite microparticles sintered together using specialty glass atop a porous Al₂O₃ porous disk that was used as a support. Fourier transform infrared spectroscopy and x-ray diffraction analysis was used to confirm that the natural clinoptilolite used in this study maintains its overall structural conformation following heat treatment as high as 1073 K. Surface and cross-sectional scanning electron microscopy imagery of the prepared membranes showed the formation of a porous clinoptilolite – glass composite layer and a mostly glass layer with lesser porosity. Single gas He, CO₂, CH₄, and N₂ permeation experiments were carried out to evaluate the initial performance parameters of the membranes. Single gas membrane permeation decreased with increasing amount of glass, and ranged from 2 × 10⁻⁷mol/m²s Pa for the membrane prepared with 30 wt. % clinoptilolite as filler to as high as 4 × 10⁻⁶mol/m²s Pa for the 50 wt. % clinoptilolite membrane. The ideal selectivity was calculated from the single gas permeance for potential natural gas or biogas CH₄/N₂ and CO₂/CH₄ separations. These values were the highest at 1.7 ± 0.2 and 1.9 ± 0.1 for the membranes prepared with 40 wt. % and 30 wt. % clinoptilolite, respectively. Considerable refinements to this technique are necessary in order to minimize the presence defects before it may be used as an alternative to inorganic membranes or mixed matrix membranes as an approach when zeolite crystallization is difficult to achieve.

摘要

在这项研究中，我们交流了我们关于开发新型无机复合斜发沸石膜的初步发现。膜由天然斜发沸石微粒在用作支撑的多孔Al ₂ O _{3多孔盘上使用特种玻璃烧结在一起形成。}傅里叶变换红外光谱和 X 射线衍射分析用于确认本研究中使用的天然斜发沸石在高达 1073 K 的热处理后保持其整体结构构象。制备的膜的表面和横截面扫描电子显微镜图像显示形成多孔斜发沸石-玻璃复合层和孔隙率较小的大部分玻璃层。单一气体 He, CO ₂ , CH_如图4所示，进行N ₂渗透实验以评估膜的初始性能参数。单层气体膜的渗透率随着玻璃用量的增加而降低，对于用 30 ^{wt .}％斜发沸石作为填料高达 4 × 10 ^-6 mol/m ² s Pa 对于 50 wt. ％斜发沸石膜。根据潜在天然气或沼气 CH ₄ /N ₂和 CO ₂ /CH _{4的单一气体渗透率计算理想选择性}分离。对于用 40 wt. 制备的膜，这些值最高，分别为 1.7 ± 0.2 和 1.9 ± 0.1。% 和 30 重量。％斜发沸石，分别。当沸石结晶难以实现时，该技术可用作无机膜或混合基质膜的替代品，以最大限度地减少存在的缺陷，因此需要对该技术进行相当大的改进。