Preparation Of Natural Gas Dehydration Membrane Using Environmentally Friendly MOF

Natural gas is extracted from underground formations or seabed,it usually contains impurities such as saturated water vapor causing danger and reducing the value of natural gas during the transportation.Therefore,it is very important to dehydrate the natural gas before it is transported.In this paper,the synthesized zirconium-based metal-organic frameworks and novel mixed matrix membranes were characterized by X-ray diffraction,BET,Fourier transform infrared spectroscopy,scanning electron microscopy,and thermogravimetric analysis.The results showed that MIP-202,Ui O-66-SO₃H and mixed matrix membranes were all successfully prepared,the two MOFs were well dispersed in PEI;and the prepared PEI/MIP-202 MMMs and PEI/Ui O-66-SO₃H MMMs has better thermal stability than pure PEI film.The dehydration performance of natural gas was tested on the synthesized mixed matrix membranes.The optimal H₂O/CH₄ separation ratios of PEI-based MMMs loaded with 20 wt%MIP-202 and PEI-based MMMs loaded with 20 wt%Ui O-66-SO₃H were as high as 832.2 and 852,respectively;The novel mixed-matrix membranes had better H₂O/CH₄ separation performance.In addition,when the PEI-based MMMs loaded with25 wt%MIP-202 was coated with dopamine for 8 h,the optimal separation rate of H₂O/CH₄ was 790.7,which was higher than that of the uncoated 25 wt%PEI/MIP-202MMMs（738.4）.The above studies showed that the separation performance of pure polymer membranes can be effectively improved by incorporating metal organic framework materials to prepare novel mixed matrix membranes,providing a green and efficient path for natural gas dehydration technology.