Water Vapor Removal from Gas Streams Using Nano-Structured Zeolites

Natural gas is considered as a mixture of methane, as main component, and other gases. The presence of these gases in natural gas and others could make difficulties in their utilization in various fields such as electricity generation, vehicle fuels and energy resources. H2O as an important impurity would cause hydrate formation and pipeline and equipment blockage as well as corrosion in the presence of acidic gases like H2S and CO2 [1]. There have been many reports on the investigation of dehydration of gas streams through different methods. In this regards, using adsorbents with high dehydration capacity is a promising idea. Zeolites as a key group of molecular sieves with high surface area, thermal and chemical stability and being low-cost sorbents beseem appropriate candidates [2]. To the best of our knowledge, there was not any report on evaluating the ability of nanostructured zeolite 4A in water removal from gas mixtures including methane. In this study, zeolite 4A was synthesized via hydrothermal route. The zeolitic gel underwent ageing stage during different times. Then, the milky gel was transferred into a stainless steel autoclave and put into an oven at 100˚C for certain time. The final white powder was washed with deionized water, dried and characterized using X-ray diffraction pattern (XRD) and scanning electron microscopy (SEM) techniques. As shown in Fig. 1, the cubic morphology has been obtained for the zeolite LTA crystals. Moreover, an adsorption set-up comprising a gas mixture cylinder, sorbent reactor and a humidity analyzer has been designed. It is a novel idea to gain outstanding dehydration results due to the hydrophilic nature and small particle size of as-synthesized zeolites