Latest Development on Membrane Fabrication for Natural Gas Purification: A Review

Table 3

Few researches of mixed matrix membranes.

Year	Mixed matrix membrane (MMM)		Observations	Ref.
	Organic	Inorganic
1973	Silicon rubber	Molecular sieves	Poor adhesion of organic and inorganic selected leads to poor separation performance.; This poor interaction of both materials may result in nonselective voids present at the interface which consequently causes insufficient membrane performance [41–43].	[44]
1992	Polydimethylsiloxane (PDMS)	Silicalite-1, 13X, KY, and zeolite-5A	Zeolite like silicalite-1, 13X, and KY have enhanced the separation performance of poorly selective rubbery membrane for the carbon dioxide (CO2) and methane (CH4) mixture.	[45]
	Propylene diene rubber (EPDM)		Zeolite-5A showed no change in gas selectivity with decrease permeability due to impermeable characteristic towards CO2.
2000	Cellulose acetate (CA)	Silicalite, NaX, and AgX	Silicalite did in fact reverse the selectivity of CA membrane from H2 to CO2 for CO2/H2 separation.	[46]
2000	Polyvinyl acetate	4A	Formation of chemical bonds gave good adhesion, but there is still nonselective “leakage” from the existence of nanometric region.	[47]
2003	Matrimid	Carbon molecular sieves	Selectivity of CO2/CH4 mixture has increased up to 45%.; Zeolites loading also affects both gas permeability and gas mixture selectivity. There were also a number of records where permeability increased with selectivity decreased as the zeolites loading was increased [48, 49] and vice versa [42].	[50]
2006	Polyethersulfone (PES)	Zeolite 4A	Due to low mobility of the polymer chain in glassy polymer such as to prevent them to completely cover the zeolites surface which resulted in void interface [51, 52].	[53]
2001	Polyimide (PI)	Zeolite 13X		[54]
2008	Polycarbonate	Zeolite 4A		[55]