本文選題：小孔沸石分子篩膜　切入點(diǎn)：鈀復(fù)合膜　出處：《大連理工大學(xué)》2015年碩士論文　論文類型：學(xué)位論文

【摘要】：在環(huán)境問題日益嚴(yán)重的今天,氫氣作為一種綠色的能源得到了普遍的青睞,然而氫氣是一種二次能源,需要通過水煤氣法、石油熱裂解等方法制備得到,但這些方法同時(shí)還會(huì)產(chǎn)生CO2、N2及一些含碳化合物等副產(chǎn)物,因此對(duì)于氫氣提純的研究顯得至關(guān)重要。沸石分子篩膜作為一種新型的無機(jī)膜材料在氣體分離領(lǐng)域己成為研究熱點(diǎn)。按照孔道結(jié)構(gòu)和孔徑的大小,沸石通�？梢苑譃樾】住⒅锌�、大孔材料等,其中一些小孔沸石分子篩如SAPO-34 (0.38x0.38 nm)、DDR (0.36x0.44 nm)等具有與某些小分子氣體直徑相當(dāng)?shù)目讖?并同時(shí)兼有沸石材料良好的熱力學(xué)穩(wěn)定性等,因此可用于一些小分子氣體的分離領(lǐng)域中。另外,在氫氣分離領(lǐng)域中,鈀膜由于具有優(yōu)異的透氫選擇性,一直都是研究的熱點(diǎn)。本文在結(jié)合對(duì)現(xiàn)有工藝的分析,提出了適合工業(yè)化發(fā)展的研究方案,主要內(nèi)容如下：(1)應(yīng)用蒸汽相轉(zhuǎn)化涂晶法,在廉價(jià)大孔α-Al2O3陶瓷管載體上均勻涂覆晶種,通過二次生長(zhǎng)法合成出性能較好的SAPO-34沸石分子篩膜。在氣體滲透性能測(cè)試中,常溫下H2的通量可達(dá)6.724×10-6mol·m-2s-1Pa-1,而且氫氣的分離選擇性H2/CO2、H2/N2、 H2/CH4、H2/C3H8及H2/i-C4H10分別為1.813、7.479、14.337、27.445及54.226。(2)為提高SAPO-34沸石膜分離H2與其他氣體分子的分離選擇性,本文提出應(yīng)用化學(xué)鍍法制備Pd/SAPO-34復(fù)合膜。制備得到的復(fù)合膜對(duì)于氫氣的選擇性有很大提高,測(cè)試溫度為573K時(shí),H2/CO2、H2/N2、H2/CH4的選擇性分別為65、96、182,H2通量達(dá)8.29×10-7 mol·m-2s-1Pa-1;當(dāng)測(cè)試溫度為873K時(shí),分離效果達(dá)最佳,H2/CO2、H2/N2、H2/CH4的分離選擇性分別為182、215、377,H2通量達(dá)3.04x10-6mol·m-2s-1Pa-1。(3)在大孔α-Al2O3載體上合成DDR前驅(qū)體沸石膜并負(fù)載鈀膜進(jìn)行修飾,以提高沸石膜的透氫選擇性。在制備DDR沸石膜的過程中為避免發(fā)生轉(zhuǎn)晶,縮短沸石膜的合成時(shí)間,形成DDR型沸石前驅(qū)體膜層,并應(yīng)用化學(xué)鍍法制備Pd/DDR-precursor復(fù)合膜。當(dāng)測(cè)試溫度為873K時(shí),分離效果達(dá)到最佳,H2/CO2、H2/N2、H2/CH4的選擇性分別為170、185、305,H2通量達(dá)1.91×10-6 mol·m-2s-1Pa-1。
[Abstract]:In today's increasingly serious environmental problems, hydrogen, as a green energy, is generally favored. However, hydrogen is a kind of secondary energy, which needs to be prepared by water gas method, petroleum pyrolysis and so on. But these methods also produce by-products such as CO _ 2N _ 2 and some carbohydrates. As a new inorganic membrane material, zeolite membrane has become a hot topic in the field of gas separation. According to the pore structure and pore size, zeolite can be divided into small pores. Mesoporous and macroporous materials, and some microporous zeolites, such as SAPO-34 0.38 x 0.38 nmdr 0.36 x 0.44 nm, have the same pore diameter as some small molecular gases, and also have good thermodynamic stability of zeolite materials, etc. Therefore, it can be used in the field of separation of small molecular gases. In addition, in the field of hydrogen separation, Palladium membrane has been a hot research area because of its excellent hydrogen permeation selectivity. A research scheme suitable for industrial development was put forward. The main contents were as follows: (1) by using steam phase transformation coating method, the crystal seeds were uniformly coated on the carrier of cheap macroporous 偽 -Al 2O 3 ceramic tube. SAPO-34 zeolite membranes with good performance were synthesized by secondary growth method. The H _ 2 flux can reach 6.724 脳 10 ~ (-6) mol 路m ~ (-2) s ~ (-1) Pa-1 at room temperature, and the selectivity of H _ 2 / CO _ (2) O _ (2) H _ (2) N _ (2) N _ (2), H _ 2 / Ch _ (4) C _ (2) C _ (3H _ 8) and H _ (2 / -C _ 4H _ (10)) are 1.813 ~ 7.47914.3327.445 and 54.226.2 respectively) to improve the selectivity of separation of H _ 2 from other gas molecules by SAPO-34 zeolite membrane. In this paper, Pd/SAPO-34 composite membranes were prepared by electroless plating. The hydrogen selectivity of the composite membranes was greatly improved at 573K. The selectivity of H _ 2 / CO _ 2 / H _ 2 / N _ 2H _ 2 / Ch _ 4 was 6.5 脳 10 ~ (-7) mol 路m ~ (-1) 路m ~ (-1) Pa-1 for H _ 2 / H _ 2 / H _ 2 / Ch _ 4, and 8.29 脳 10 ~ (-7) mol 路m ~ (-2) 路m ~ (-1) Pa-1 for H _ 2 / CO _ 2 / H _ 2 / H _ 2 / Ch _ 4 respectively. The separation selectivity of H _ 2 / CO _ 2 / H _ 2 / N _ 2N _ 2 / H _ 2 / Ch _ 4 was 182N _ (2) C _ (2) O _ (2) H _ (2) H _ 2 flux of 3.04x10-6 mol 路m ~ (-2) -1Pa-1.3) DDR precursor zeolite membrane was synthesized on macroporous 偽 -Al _ 2O _ 3 carrier and modified with palladium membrane. In order to improve the hydrogen permeation selectivity of zeolite membrane, in order to avoid transpamination and shorten the synthesis time of zeolite membrane, DDR zeolite precursor membrane was formed in the process of preparing DDR zeolite membrane. The Pd/DDR-precursor composite membrane was prepared by electroless plating. When the test temperature was 873 K, the optimum separation efficiency was obtained. The selectivity of H _ 2 / H _ 2 / H _ 2 / Ch _ 4 was 1. 91 脳 10 ~ (-6) mol m ~ (-2) -2 路s ~ (-1) Pa-1, respectively, and the selectivity of H _ 2 / Ch _ 4 was 1.91 脳 10 ~ (-6) mol ~ (-2) -2s ~ (-1) Pa-1.
【學(xué)位授予單位】：大連理工大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2015
【分類號(hào)】：TQ116.2;TQ051.893

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相關(guān)期刊論文 前1條

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本文編號(hào)：1644560