Enhancing the CO₂ separation performance of composite membranes by the incorporation of amino acid-functionalized graphene oxide

Abstract

Amino acid-functionalized graphene oxide nanosheet-incorporated composite membranes significantly enhanced the CO2/CH4(N2) diffusivity, reactivity and solubility selectivities.

The preparation of SPEEK/phosphate salts membranes and application for CO2/CH4 separation

“…The membranes doped with NaH 2 PO 4 , Na 2 HPO 4 and Na 3 PO 4 showed the stretching vibration peaks of P@O at 1415, 1402, and 1437 cm 21 , these characteristic bands suggested that the phosphate salts were successfully introduced into the polymer matrix. All membranes showed the representative peaks of -OH at the position of 3445 cm 21 , phosphate salts were presented in SPEEK membranes, the corresponding peak intensity increased, which indicating the enhance hydrophilic of membranes.…”

“…) is higher than that of sulfonic acid with water molecule (44.4 KJ mol 21 ), 27 which indicated that phosphonic acid has easier capacity to bind with water molecule and retained more water. Furthermore, phosphate salts has different acid-base properties, the acid2base interaction between salts and CO 2 could increase the solubility of CO 2 .…”

“…Fourier transform infrared spectrometer (FTIR, Nicolet AVATAR 360) were recorded for pure SPEEK and SPEEK/phosphate salts membranes with the scan range of 400 2 4000 cm 21 .…”

“…Khan and co-workers prepared SPEEK membranes and found that the gas permeability and selectivity simultaneously increase when the sulfonation degree and the valent of counterions of membranes increased. 16 In addition, SPEEK/ Matrimid blend membranes 17 and SPEEK/inorganic hybrid membranes, [18][19][20][21] such as -SO 3 functionalized mesoporous MCM-41, amine-functionalized metal organic frameworks, TiO 2 and amino acid-functionalized graphene oxide, were studied and used for separation CO 2 from gas mixture. The results suggested that the increase of fractional free volume facilitated the transport of CO 2 by modified SPEEK with nanoinorganic particles.…”

Widening CO2-facilitated transport passageways in SPEEK matrix using polymer brushes functionalized double-shelled organic submicrocapsules for efficient gas separation

“…Mixed matrix membranes (MMMs) composed of an inorganic filler and a polymer matrix have exhibited the potential of surpassing the trade-off limit [1,[4][5][6][7][8][9][10][11][12]. Fillers such as porous zeolite [13,14], silica nanoparticles [15,16], carbon nanotubes (CNTs) [9,17,18] metal-organic frameworks [19][20][21][22][23], and graphene oxide [24,25] have been doped in different polymer matrix to develop new MMMs with improved gas separation performance.…”