本實驗以酸鹼雙功能觸媒-水滑石衍生氧化物進行乙醇轉化為四碳產物之研究。乙醇轉化為四碳產物為複雜的反應系統，包含脫水、脫氫、醇醛縮合反應等可能同時進行。其中乙醇脫氫為乙醛，是進行醇醛縮合形成四碳產物的重要前驅物。因此，本研究著眼觸媒表面之改質，希冀增加脫氫之進行並減少脫水產物生成。以水滑石衍生之鎂鋁氧化物，擔載於官能化的氧化矽與碳材上作為觸媒，並探討觸媒物化性質對於乙醇轉化之影響。從初始反應條件的結果得知，水滑石衍生氧化物在Mg/Al=3為最佳組成，此組成有較佳之脫氫與醇醛縮合活性。將MgO-Al2O3擔載至二氧化矽後，主要的四碳產物為丁二烯。隨著氧化矽表面羥基增加，觸媒脫氫與醇醛縮合活性提升。為了確立觸媒改質對整體反應之路徑影響，本研究以反應中間物乙醛與乙醇共同進料進行測試，結果得知丁二烯選擇率大幅提升，證實乙醛為關鍵中間產物。後續以另一中間產物巴豆醛(2-butenal)與乙醇共同進料，證實不同載體對於產物選擇率並無明顯改變，說明後續MPV、脫水反應並未受到載體變化之影響。
將載體改為碳材進行比較，驗證觸媒合成過程中，易受到載體表面官能化之影響。本實驗以硝酸酸洗方式對碳材表面官能化，制造表面酸根及空缺。反應性結果顯示，擔載至官能化載體，觸媒脫氫能力提升，乙醛產物選擇率增加。由CO2-FTIR結果亦顯示，鹼性點分佈往中強鹼位移，與二氧化矽載體呈現相同趨勢。說明載體經表面處理後，提高水滑石分散度，使觸媒與載體界面，形成較多中強鹼Mg2+-O2-鍵結，促進乙醛產物生成之結果。

Hydrotalcite derived oxide are prepared via the co-precipitation method and supported on functionalized SiO2. The acid-base catalysis and structural properties were investigated. MgO-Al2O3/SiO2 catalysts (using Dehy-SiO2, Nor-SiO2, and Rehy-SiO2 as SiO2 supports) exhibited higher activities of dehydrogenation and aldol condensation than conventional bulk MgO-Al2O3 catalyst. X-ray diffraction (XRD) pattern suggests that the addition of SiO2 promotes dispersion of hydrotalcite derived Mg-Al oxide. XPS results suggest that a unique Mg-Si interaction can be formed on MgO-Al2O3/SiO2 catalysts. According to CO2-TPD and CO2-FTIR results, highly dispersed MgO-Al2O3 on silica can increase the strength and the amount of the medium basic strength sites. The medium basic site is critical in catalyzing the dehydrogenation of ethanol, and therefore can further enhance subsequent aldol condensation to increase butadiene selectivity.

1. RFA’s Ethanol Industry Outlook. 2015

2. Laird, K., Bio-based chemicals receive boost from shale gas boom in North America. 2014.
3. 2013 Petrochemical Industry Yearbook. 2015.
4. Goh, C.S. and K.T. Lee, A visionary and conceptual macroalgae-based third-generation bioethanol (TGB) biorefinery in Sabah, Malaysia as an underlay for renewable and sustainable development. Renewable and Sustainable Energy Reviews, 2010. 14(2): p. 842-848.
5. John, R.P., et al., Micro and macroalgal biomass: A renewable source for bioethanol. Bioresource Technology, 2011. 102(1): p. 186-193.
6. Saxena, R.C., D.K. Adhikari, and H.B. Goyal, Biomass-based energy fuel through biochemical routes: A review. Renewable and Sustainable Energy Reviews, 2009. 13(1): p. 167-178.
7. Makshina, E.V., et al., Review of old chemistry and new catalytic advances in the on-purpose synthesis of butadiene. Chemical Society Reviews, 2014. 43(22): p. 7917-7953.
8. V. N. Ipatieff, J.R., Phys.-Chem. Soc, 1903. 35: p. 449–452.
9. S. V. Lebedev, FR, 1929. p. 665917
10. S. V. Lebedev, Z.O.K., 1933: p. 698-717.
11. Bhattacharyya, S.K. and B.N. Avasthi, Catalytic conversion of ethanol to butadiene by two-step process in fluidised bed. Journal of Applied Chemistry, 1966. 16(8): p. 239-244.
12. Corson, B.B., et al., Butadiene from Ethyl Alcohol. Industrial & Engineering Chemistry, 1949. 41(5): p. 1012-1017.
13. Hiroo, N., M. Saburo, and E. Etsuro, Butadiene Formation from Ethanol over Silica-Magnesia Catalysts. Bulletin of the Chemical Society of Japan, 1972. 45(3): p. 655-659.
14. Kvisle, S., A. Aguero, and R.P.A. Sneeden, Transformation of ethanol into 1,3-butadiene over magnesium oxide/silica catalysts. Applied Catalysis, 1988. 43(1): p. 117-131.
15. Ohnishi, R., T. Akimoto, and K. Tanabe, Pronounced catalytic activity and selectivity of MgO-SiO2-Na2O for synthesis of buta-1,3-diene from ethanol. Journal of the Chemical Society, Chemical Communications, 1985(22): p. 1613-1614.
16. León, M., E. Díaz, and S. Ordóñez, Ethanol catalytic condensation over Mg–Al mixed oxides derived from hydrotalcites. Catalysis Today, 2011. 164(1): p. 436-442.
17. Toussaint, W.J., J.T. Dunn, and D.R. Jachson, Production of Butadiene from Alcohol. Industrial & Engineering Chemistry, 1947. 39(2): p. 120-125.
18. B, C.B., industrial and engineering chemistry, 1950. 42: p. 359–373.
19. Bhattacharyya, S.K. and N.D. Ganguly, One-step catalytic conversion of ethanol to butadiene in the fixed bed. II BINARY- AND TERNARY-OXIDE CATALYSTS. Journal of Applied Chemistry, 1962. 12(3): p. 105-110.
20. Kitayama, Y. and A. Michishita, Catalytic activity of fibrous clay mineral sepiolite for butadiene formation from ethanol. Journal of the Chemical Society, Chemical Communications, 1981(9): p. 401-402.
21. Kitayama, Y.S., M.; Kodama, T. , Catal. Lett. , 1996. 36: p. 95-97.
22. Jones, M.D., Catalytic transformation of ethanol into 1,3-butadiene. Chemistry Central Journal, 2014. 8(1): p. 53.
23. Makshina, E.V., et al., Catalytic study of the conversion of ethanol into 1,3-butadiene. Catalysis Today, 2012. 198(1): p. 338-344.
24. Angelici, C., et al., Effect of Preparation Method and CuO Promotion in the Conversion of Ethanol into 1,3-Butadiene over SiO2–MgO Catalysts. ChemSusChem, 2014. 7(9): p. 2505-2515.
25. Quattlebaum, W.M., W.J. Toussaint, and J.T. Dunn, Deoxygenation of Certain Aldehydes and Ketones: Preparation of Butadiene and Styrene1. Journal of the American Chemical Society, 1947. 69(3): p. 593-599.
26. Stahly, E.E., H.E. Jones, and B.B. Corson, Butadiene from Ethanol. Industrial & Engineering Chemistry, 1948. 40(12): p. 2301-2303.
27. Jones, H.E., E.E. Stahly, and B.B. Corson, Butadiene from Ethanol. Reaction Mechanism. Journal of the American Chemical Society, 1949. 71(5): p. 1822-1828.
28. I. I. Ostromyslensky, J.R., Phys.-Chem. Soc, 1915. 47: p. 359–373.
29. Doklady Biochemistry, 1957. 112: p. 1075.
30. Ezinkwo, G.O., et al., Fundamental Issues of Catalytic Conversion of Bio-Ethanol into Butadiene. ChemBioEng Reviews, 2014. 1(5): p. 194-203.
31. Khim., S., Doklady Biochemistry, 1947: p. 173.
32. Di Cosimo, J.I., et al., Structure and Surface and Catalytic Properties of Mg-Al Basic Oxides. Journal of Catalysis, 1998. 178(2): p. 499-510.
33. Morterra, C., et al., An infrared spectroscopic investigation of the surface properties of magnesium aluminate spinel. Journal of Catalysis, 1978. 51(3): p. 299-313.
34. Philipp, R. and K. Fujimoto, FTIR spectroscopic study of carbon dioxide adsorption/desorption on magnesia/calcium oxide catalysts. The Journal of Physical Chemistry, 1992. 96(22): p. 9035-9038.
35. Corma, A., V. Fornes, and F. Rey, Hydrotalcites as Base Catalysts: Influence of the Chemical Composition and Synthesis Conditions on the Dehydrogenation of Isopropanol. Journal of Catalysis, 1994. 148(1): p. 205-212.
36. Ochoa, J.V., et al., An analysis of the chemical, physical and reactivity features of MgO-SiO2 catalysts for butadiene synthesis with the Lebedev process. Green Chemistry, 2016. 18(6): p. 1653-1663.
37. Cavani, F., F. Trifirò, and A. Vaccari, Hydrotalcite-type anionic clays: Preparation, properties and applications. Catalysis Today, 1991. 11(2): p. 173-301.
38. Zhu, Q., B. Wang, and T. Tan, Conversion of Ethanol and Acetaldehyde to Butadiene over MgO–SiO2 Catalysts: Effect of Reaction Parameters and Interaction between MgO and SiO2 on Catalytic Performance. ACS Sustainable Chemistry & Engineering, 2017. 5(1): p. 722-733.
39. Janssens, W., et al., Ternary Ag/MgO-SiO2 Catalysts for the Conversion of Ethanol into Butadiene. ChemSusChem, 2015. 8(6): p. 994-1008.