Molecular Sieve Solid Super Acid, Alkali, And Catalyzed Applied Research

Solid superacid and solid superbase are important parts of industrial catalyst, which are also hot spots of catalyst realm in recent years. Those kinds of catalyst attract close respect of the domestic and foreign chemistry researchers, because of high acidic or basic strength, high catalytic activity, relatively low catalytic temperature, easy to be separated from the reaction system, reusable and renewable, no corrosion to equipments, and no pollution to environment. But the traditional solid superacid and solid superbase catalysts which usually use ZrO2, TiO2 or Al2O3 as the carrier have small surface area and have not rich and neat pore structure. In order to remedy this defect, a zeolite-type solid superacid or superbase was attempted to be prepared with molecular sieve as the carrier. Mesoporous molecular sieves have neat pore structure, large surface area, adjustable aperture, good thermal stability and catalytic selectivity, which open up broad application way for catalysis and adsorption of macromolecular compound. A new zeolite-type solid superacid or superbase catalyst which not only has high acidic or basic strength and high catalytic activity of solid superacid and superbase, but also has neat pore structure and high catalytic selectivity of molecular sieves was prepared combined with both advantages, which will help to increase the activity and selectivity of catalysts, to reduce reaction temperature, and will be more conducive to industrial catalytic applications.In this paper, with Al-MCM-41 molecular sieve as the carrier, the active components of solid superacid or superbase were loaded in the surface and skeleton structure of mesoporous molecular sieve and a zeolite-type solid superacid SO42-/Ti02-Sn02-Al-MCM-41 and a zeolite-type solid superbase 2Na+O2-/Al-MCM-41 were respectively prepared successfully, and the applications of these two catalysts in organic synthesis were studied preliminary.In the first chapter of this paper, an overview of the development of mesoporous molecular sieves, solid superacid and solid superbase in recent years were provided, and the advantages and disadvantages of traditional solid superacid and superbase catalysts were summarized. In view of the defects of traditional solid superacid and superbase catalysts, the topic research plan was proposed.In the second chapter of this paper, based on the original research of our laboratory, the catalyst SO42-/TiO2-Al-MCM-41 was improved because it had short service life and was sensitive to water, and with the Al-MCM-41 as the carrier, a zeolite-type solid superacid catalyst SO42-/TiO2-SnO2-Al-MCM-41 supported titanium and tin was prepared by impregnation method. The structure and surface properties of the obtained materials were characterized by XRD, FT-IR, SEM, TG-DTA, BET, NH3-TPD, the acid strength of determination and other testing methods. The results showed that the obtained catalyst had rich and neat mesoporous structure, the specific surface was 500.03 m2/g, the acid strength H0<16.04, and it belonged to zeolite-type solid superacid catalyst.In the third chapter of this paper, the new zeolite-type solid superacid catalyst SO42-/TiO2-SnO2-Al-MCM-41 was used in preparation of dioctyl phthalate, di(p-methoxybenzal)pentaerythritol, and the esterification reaction of rice bran oil, and the catalyst showed high catalytic activity. Through optimizing the reacyion conditions, the yield of dioctyl phthalate was up to 99.93%, the yield of di(p-methoxybenzal)pentaerythritol was up to 90.5%, and FFA of rice bran oil acid value could be reduced from 23.70% to 3.88%. The effect of this catalyst was superior to the traditional solid superacid catalysts, and the defects of the catalyst SO42-/TiO2-Al-MCM-41 were overcome.In the forth chapter of this paper, with the Al-MCM-41 as the carrier, a zeolite-type solid superbase catalyst 2Na+O2-/Al-MCM-41 was prepared by successively reacted with NaOH and Na in a high temperature. The obtained materials were characterized by XRD, FT-IR, BET, SEM, TEM, the base strength, basicity and other testing methods. The results showed as follows: compared to the same kind of solid superbase catalyst, the obtained catalyst had rich pore structure, the specific surface was 276.06 m2/g, the base strength H≥37, the basicity was up to 6.2 mmol/L and it belonged to the strongest solid superbase catalyst.In the fifth chapter of this paper, the new solid superacid catalyst 2Na+O2-/Al-MCM-41 was used in preparation of bis-benzalacetone, celery ketone and biodiesel, and the catalyst showed high catalytic activity. Through optimizing the reacyion conditions, the yield of bis-benzalacetone was up to 89.65%, the yield of celery ketone was up to 87.6%, and the yield of biodiesel was up to 92.6%. The methodology of catalysis has good industrial prospects, because of high catalytic activity, no corrosion to equipments, and no pollution to environment.