本文選題：鈣基固體堿 + 多相催化�。� 參考：《華中農(nóng)業(yè)大學(xué)》2015年碩士論文

【摘要】：隨著化石燃料的逐漸枯竭、環(huán)境問題的日益凸顯,生物柴油作為一種清潔、可再生的生物質(zhì)能源已成為世界各國關(guān)注的焦點(diǎn)。非均相固體堿催化劑可以使生物柴油的工業(yè)化生產(chǎn)過程更加“綠色化”,制備出廉價(jià)、高效的固體堿催化劑對于生物柴油的規(guī)�；a(chǎn)具有重要意義。本文制備了兩種鈣基固體堿催化劑用于催化菜籽油合成生物柴油,并采用多種現(xiàn)代技術(shù)手段對催化劑進(jìn)行表征。主要研究結(jié)果如下:1.用KF浸漬Ca O-La2O3制備了具有高催化活性的KF/Ca O-La2O3催化劑。KF/Ca O-La2O3催化劑最佳制備條件為:La2O3的添加量為15 wt%,煅燒溫度為600℃,煅燒時(shí)間為3h。用XRD、低溫N2吸附-脫附、SEM、TEM以及Hammett指示劑法表征了催化劑的晶相結(jié)構(gòu)、形貌以及堿強(qiáng)度。煅燒后的催化劑的主要晶相是Ca O、KCa F3和La OF,優(yōu)化條件下制備的催化劑呈圓球狀,催化劑有一定的團(tuán)聚,可以清晰的看到其多孔結(jié)構(gòu),催化劑比表面積為0.96m2/g,孔體積為0.0057cm3/g,平均孔徑為24.7nm,催化劑的堿強(qiáng)度為15.0H—18.4。優(yōu)化了催化劑用于酯交換反應(yīng)的條件,在溫度為65℃,催化劑用量為4 wt%,醇油摩爾比為12:1的條件下,反應(yīng)80min,FAME產(chǎn)率可達(dá)97.3%。KF/Ca O-La2O3重復(fù)使用5次后產(chǎn)率仍可達(dá)70%以上。2.浸漬法制備了KF/Ca O-MSP催化劑。用XRD、低溫N2吸附-脫附、SEM、TEM以及Hammett指示劑法表征了催化劑的晶相結(jié)構(gòu)、形貌以及堿強(qiáng)度。煅燒后的催化劑的主要晶相是Ca O、KCa F3和KCa CO3F,優(yōu)化條件下制備的催化劑可明顯觀察到其多孔結(jié)構(gòu),催化劑比表面積為1.04m2/g,孔體積為0.0048cm3/g,平均孔徑為18.5nm,催化劑的堿強(qiáng)度為9.8H—15.0。在優(yōu)化制備條件后的催化劑在溫度為65℃,催化劑用量為4 wt%,醇油摩爾比為12:1,反應(yīng)時(shí)間為150min的條件下,FAME產(chǎn)率可達(dá)95.3%。3.通過對KF/Ca O-La2O3和KF/Ca O-MSP兩種催化劑制備過程的研究,發(fā)現(xiàn)KF/Ca O-La2O3在催化酯交換反應(yīng)前后形態(tài)幾乎未發(fā)生改變,表現(xiàn)出良好的機(jī)械強(qiáng)度;而KF/Ca O-MSP呈粉狀,易碎,強(qiáng)度明顯較差。同時(shí)對KF/Ca O-La2O3和Ca O進(jìn)行了機(jī)械強(qiáng)度比較,發(fā)現(xiàn)KF/Ca O-La2O3催化劑極限正壓力均值25.2Kg,Weibull模量m為6.37,說明KF/Ca O-La2O3不僅有較高的強(qiáng)度,而且具有較高的強(qiáng)度可靠性,在生物柴油領(lǐng)域有較好的應(yīng)用前景。4.通過研究發(fā)現(xiàn),負(fù)載KF的鈣基催化劑中產(chǎn)生的新晶相KCa F3不是活性晶相,不能催化油脂與甲醇的酯交換反應(yīng)。
[Abstract]:With the gradual depletion of fossil fuels and the increasingly prominent environmental problems, biodiesel, as a clean and renewable biomass energy, has become the focus of attention all over the world. Heterogeneous solid base catalyst can make the industrial production process of biodiesel more "green", and the preparation of cheap and efficient solid base catalyst is of great significance for the large-scale production of biodiesel. In this paper, two kinds of calcium based solid base catalysts were prepared to catalyze the synthesis of biodiesel from rapeseed oil, and the catalysts were characterized by various modern techniques. The main results are as follows: 1. KF / CaO-La _ 2O _ 3 catalyst with high catalytic activity was prepared by impregnation of KF with CaO-La _ 2O _ 3. The optimum conditions for preparation of KF / Ca _ O-La _ 2O _ 3 catalyst were as follows: the addition amount of W _ 2O _ 3 was 15 wt, the calcination temperature was 600 鈩，

本文編號：2061390