【摘要】：隨著分離技術(shù)的發(fā)展,氫氣的純化日益受到人們的關(guān)注,本課題擬基于高長(zhǎng)徑比的陶瓷中空纖維負(fù)載氧化石墨烯膜以提高膜的強(qiáng)度和分離性能。為此,采用高強(qiáng)度的YSZ(8%Y_2O_3摻雜的Zr O_2)基于相轉(zhuǎn)化法制備多孔中空纖維陶瓷膜,通過(guò)真空輔助的抽濾法負(fù)載超薄氧化石墨烯(Graphene oxide,GO),形成GO/YSZ復(fù)合膜,GO膜厚度大約為230nm。GO片層之間的2D納米孔道及表面缺陷使此種膜具有了分子篩功能,20 ℃時(shí)H_2和N_2兩種單組分氣體的滲透能力分別為4.4×10-8和5.8×10-10mol·m~(-2)·s~(-1)·Pa-1,理想分離因數(shù)高達(dá)76,而H_2/N_2混合氣的分離因數(shù)為68,這是由于組分之間相互碰撞阻礙所造成的。隨著工作溫度的升高,石墨烯膜層間距加大,使N_2的滲透速率增幅超過(guò)了H_2,因此H_2/N_2分離系數(shù)在100℃僅為37,但此種膜能穩(wěn)定運(yùn)轉(zhuǎn)240h,性能無(wú)衰減�；诜肿雍Y機(jī)理,模擬了H_2/N_2混合氣分離過(guò)程中,氫氣的分壓、滲透量在管內(nèi)的分布,結(jié)果表明,微管前端(微管進(jìn)氣口端),H_2滲透量和氫分壓急劇增加,約5cm處變化甚微,表明微管的有效滲透區(qū)域約為5cm左右;適當(dāng)增加原料氣壓力或降低滲透?jìng)?cè)壓力,都能增壓氫氣滲透量。為降低制備成本和增加GO膜與基底的結(jié)合力,又選取了含Si的Al_2O_3中空纖維膜作基底,制備GO/Si-Al_2O_3復(fù)合膜(Si摻雜Al_2O_3負(fù)載GO膜),考察了Si含量對(duì)H_2/N_2混合氣體分離性能的影響。結(jié)果表明,GO/Si-Al_2O_3復(fù)合膜也具有較優(yōu)異的氣體選擇滲透性能,20 ℃時(shí)含Si量為2wt.%的復(fù)合膜,H_2/N_2的理想選擇性為50,單氣體組分H_2和N_2的滲透量分別為1.2×10-7和2.4×10-8 mol·m~(-2)·s~(-1)·Pa-1,在長(zhǎng)達(dá)240h的運(yùn)轉(zhuǎn)過(guò)程中無(wú)膜剝離現(xiàn)象出現(xiàn)。
[Abstract]:With the development of separation technology, more and more attention has been paid to the purification of hydrogen. In order to improve the strength and separation performance of graphene oxide membrane based on high aspect ratio ceramic hollow fiber. Therefore, porous hollow fiber ceramic membranes were prepared by high strength YSZ (8%Y_2O_3 doped Zr O 2) based on phase inversion method. The ultrathin graphene oxide (Graphene oxide go) was loaded by vacuum assisted filtration method, and the thickness of GO/YSZ composite membrane was about 2D nano-pore between 230nm.GO layers and surface defects. The membrane had two kinds of molecular sieve function, H2 and N2 at 20 鈩，

本文編號(hào)：2187520