發(fā)布時間：2018-03-14 01:21

  本文選題：固相法　切入點：MIEC　出處：《東北石油大學》2017年碩士論文　論文類型：學位論文

【摘要】：木質(zhì)素是生物質(zhì)中除纖維素外含量第二的可再生資源,具有儲量豐富、再生速度快等優(yōu)點。木質(zhì)素結(jié)構(gòu)有豐富的官能團,如碳鏈、芳香環(huán)、甲氧基、羥基和羧基等,可以作為生產(chǎn)酚類等高附加值的精細化學品原料。在木質(zhì)素熱解過程中加入催化劑可以降低其選擇性斷鍵等反應活化能、提高反應速率、調(diào)節(jié)目的產(chǎn)物的選擇性和收率。通過設計和開發(fā)具有高選擇性催化劑可以選擇性活化、斷裂某一類化學鍵,選擇性催化制備某一類化學品,提高其經(jīng)濟性,實現(xiàn)木質(zhì)素環(huán)境友好型轉(zhuǎn)化利用。通過化學方法將甘蔗渣木質(zhì)素催化轉(zhuǎn)化為化學品是實現(xiàn)其資源化和高值化利用的重要途徑之一。本文采用固相法制備了一系列鈣鈦礦型混合離子電子導體(MIEC)CaZr1-xFexO3和LaTi1-xFex O3,通過XRD、SEM、XPS對其晶型、形貌和金屬賦存價態(tài)進行表征分析。利用熱重對甘蔗渣木質(zhì)素熱解及催化熱解過程進行分析,并采用固定床反應器對CaZr0.8Fe0.2O3和La Ti0.2Fe0.8O3催化熱解甘蔗渣木質(zhì)素性能進行評價,利用氣相色譜/質(zhì)譜對甘蔗渣木質(zhì)素催化熱解的液相產(chǎn)物進行分析。研究結(jié)果如下:(1)CaZr1-xFexO3呈粒狀或?qū)訝钪旅芙Y(jié)構(gòu),隨Fe摻雜量的增加,其特征衍射峰強度增大,且向大角度偏移,晶胞體積及晶粒尺寸減小。LaTi1-xFexO3的結(jié)構(gòu)平整,晶粒大小分布均勻一,其特征峰明顯,結(jié)晶度較好。升高溫度可以一定程度上增加衍射峰強度。增加焙燒時間不會生成新的特征峰但可以使其晶粒生長完全。(2)通過熱重對甘蔗渣木質(zhì)素反應過程進行分析,甘蔗渣木質(zhì)素失重主要發(fā)生在180-550°C。添加CaZr0.8Fe0.2O3和LaTi0.2Fe0.8O3可以加快甘蔗渣木質(zhì)素熱解反應速率,減少焦炭的生成,促進其進行催化轉(zhuǎn)化。(3)在CaZr0.8Fe0.2O3作用下,甘蔗渣木質(zhì)素催化熱解液相產(chǎn)物主要有苯類、苯酚類、愈創(chuàng)木基類、鄰苯二酚類、紫丁香基類和甲氧基芳香化合物,當甘蔗渣木質(zhì)素與CaZr0.8Fe0.2O3的質(zhì)量比為2:1時,各類產(chǎn)物其選擇性分別為25.01 wt.%、35.19 wt.%、6.18wt.%、10.68 wt.%和14.21 wt.%和8.73 wt.%。(4)當甘蔗渣木質(zhì)素與LaTi0.2Fe0.8O3的質(zhì)量比為2:1時,甘蔗渣木質(zhì)素催化熱解液相產(chǎn)物苯類、苯酚類、愈創(chuàng)木基類、鄰苯二酚類、紫丁香基類和甲氧基芳香化合物的選擇性分別為11.93 wt.%、37.08 wt.%、14.14 wt.%、6.42 wt.%、16.55 wt.%和13.88 wt.%。(5)鈣鈦礦型混合離子電子導體CaZr0.8Fe0.2O3和LaTi0.2Fe0.8O3進行木質(zhì)素的催化熱解后對其進行循環(huán)再生,對反應后的催化劑進行評價。對比反應前后催化劑的XRD和SEM等表征發(fā)現(xiàn)催化劑具有較高的催化活性和結(jié)構(gòu)穩(wěn)定性。
[Abstract]:Lignin is only second cellulose content in biomass renewable resources, has the advantages of abundant regeneration speed. The structure of lignin rich functional groups, such as carbon chain, aromatic ring, methoxy, hydroxyl and carboxyl, phenols can be used as production of high value-added fine chemicals. The addition of catalyst in the lignin pyrolysis process can reduce the reaction activation energy selective bond breaking, improve the reaction rate, adjust the product selectivity and yield. Through the design and development of the high selectivity of the catalyst can be selectively activated with a certain type of fracture, chemical bond, selective catalytic preparation of a class of chemicals, improve its economy, realize environment friendly conversion and utilization of lignin by chemical methods. The bagasse lignin catalytic conversion for chemicals is to realize its resources and high value of one of the important ways to use the. A series of perovskite type mixed ionic and electronic conductors were prepared by solid state method (MIEC) and CaZr1-xFexO3 LaTi1-xFex O3, by XRD, SEM, XPS on the crystal structure, morphology and occurrence of metal valence were characterized by thermogravimetric analysis. The bagasse lignin pyrolysis and catalytic pyrolysis process were analyzed, and the use of fixed bed reactor CaZr0.8Fe0.2O3 Ti0.2Fe0.8O3 and La on the catalytic pyrolysis of bagasse lignin properties were evaluated by gas chromatography / mass spectrometry of bagasse lignin pyrolysis liquid products were analyzed. The results are as follows: (1) CaZr1-xFexO3 in a granular or dense layered structure, with the increase of the Fe content increases, the characteristic diffraction peak intensity. And to the large angle offset, the cell volume and the reduction of grain size structure flat.LaTi1-xFexO3, grain size distribution, the characteristic peaks, better crystallinity. The increasing temperature to a certain extent. The peak intensity and diffraction. Increase roasting time without generating a new characteristic peak but can make the grain growth completely. (2) by thermogravimetry on bagasse lignin reaction process analysis, bagasse lignin loss occurs mainly by adding CaZr0.8Fe0.2O3 and LaTi0.2Fe0.8O3 at 180-550 DEG C. to accelerate bagasse lignin pyrolysis reaction rate. To reduce the coke production, promote the catalytic conversion. (3) in the presence of CaZr0.8Fe0.2O3 bagasse lignin catalytic pyrolysis liquid products are mainly benzene, phenol, catechol and guaiacol base, lilac base and methoxy aromatic compounds, when the quality of bagasse lignin and CaZr0.8Fe0.2O3 ratio 2:1, the selectivity of each product were 25.01 wt.%, 35.19 wt.%, 6.18wt.%, 10.68 wt.% and 14.21 wt.% and 8.73 wt.%. (4) when the bagasse lignin and the quality ratio of LaTi0.2Fe0.8O3 to 2:1, sugarcane Lignin residue catalytic pyrolysis liquid products of benzene, phenol, catechol and guaiacol base, selective lilac base and methoxy aromatic compounds were 11.93 wt.%, 37.08 wt.%, 14.14 wt.%, 6.42 wt.%, 16.55 wt.% and 13.88 wt.%. (5) catalytic pyrolysis of perovskite type mixed ion conductor CaZr0.8Fe0.2O3 LaTi0.2Fe0.8O3 and lignin after the recycling of the catalysts were evaluated after reaction. The catalysts before and after the comparison of XRD and SEM. The results showed that the catalytic activity of the catalyst has high and stable structure.

【學位授予單位】：東北石油大學
【學位級別】：碩士
【學位授予年份】：2017
【分類號】：O643.36;O636.2
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本文編號：1608979