苯二胺改性氧化石墨烯膜的制备及其渗透汽化性能

Preparation of phenylenediamines modified graphene oxide membranes for pervaporation

分别采用邻苯二胺(OPD)、间苯二胺(MPD)、对苯二胺(PPD)共价改性氧化石墨烯(GO)片层,采用真空抽滤法制备苯二胺改性GO膜,研究3种不同结构的苯二胺对GO膜结构和性能的影响.研究结果表明,不同结构苯二胺对GO的改性作用不同:OPD的反应活性低,对GO含氧官能团的消耗较少,可有效拓展GO膜的层间距;MPD消耗GO的含氧官能团多于OPD,也对GO膜层间距有较好的增大作用;PPD消耗更多的GO含氧官能团,其对位氨基的高反应活性导致GO片层产生堆积,对膜层间距无明显影响.OPD、MPD和PPD改性GO膜对质量分数90%乙醇/水体系的渗透通量分别为0.55、0.56和0.42 kg/(m^2·h),分离因子分别为90.58、30.78和34.49,证明苯二胺对GO有一定的改性作用.

o-Phenylenediamine(OPD),m-phenylenediamine(MPD)and p-phenylenediamine(PPD)were selected for covalently modifying graphene oxide(GO)sheets to prepare phenylenediamines modified GO membranes by vacuum filtration,and the effects of three phenylenediamines on the structure and properties of GO membrane were studied.The results show that phenylenediamines of different structures have different modification effects on GO:OPD has low reactivity and consumes less oxygen-containing functional groups of GO,which can effectively extend the interlayer distance(d-spacing)of GO membrane;MPD consumes more oxygen-containing functional groups of GO than OPD,and also increases the d-spacing of GO membrane;PPD consumes most of GO oxygen-containing functional groups due to high reactivity of the para-amino group,resulting in the accumulation of the GO sheets,and there is no significant change in the d-spacing of GO membrane.Pervaporation separation performance of three modified membranes for 90%ethanol/water system shows that the permeation flux of OPD,MPD and PPD modified GO membranes are 0.55,0.56 and 0.42 kg/(m^2·h),the separation factor are 90.58,30.78 and 34.49,respectively.It is proved that phenylenediamines have certain modification effects on GO.