Preparation Of Ultrafine Complex Solid Superacid Catalysts And Their Application In Esterification Reactions

Content: With Green Chemistry being advocated, the brand-new concept of green catalyst has been brought forward recently. The advantages of SO₄^2-/M_xO_y solid superacid are as follows: be liability to be separated from the reaction system, be helpful to the regeneration and reutilization, produced continuously, high activity and high selectivity, no corrosiveness, no pollution. Now it has been applied widely in organic chemistry. We can say it is a green catalyst that has a wide prospect of application. However, because its property such as catalytic activity is related with the preparation methods, researchers usually improved the preparation methods and reaction conditions to gain a better solid superacid.Judging from the literature, we know that ultrafine nanometer powder has better property when it is used in catalyst material because of its special surface property. Therefore, research on ultrafine powder solid superacid catalyst is one of the important researchs in the catalyst field today and in the future.The motive of this dissertation is to combine organically the merits of solid superacid and ultrafine powder materials. Furthermore, a series of solid superacids have been prepared by nanometer technique and the esterification reactions catalyzed over these solid superacids were studied. The main contents are as follows.Firstly, a series of ultrafine powder solid superacids such as SO₄^2-/ZrO₂ and SO₄^2-/Fe₂O₃ were prepared. We also prepared SO₄^2-/ZrO₂-MoO₃ and compared their catalytic activity over acetic acid and n-butanol. The reutility property of these catalysts were studied. The order of their catalytic activity is as follow: SO₄^2-/ZrO₂-MoO₃>SO₄^2-/ZrO₂>SO₄^2-/Fe₂O₃.Secondly, we did two aspects to synthesize n-Amyl acetate:â‘ we use a series of nanometer-sized complex solid superacids such as SO₄^2-/ZrO)2-CeO₂, SO₄^2-/ZrO₂ solid acid-5A zeolites and SO₄^2-/ZrO₂-HZSM5 as its catalyst at the first time ;â‘¡we prepared SO₄^2*/ZrO₂-SiO₂-Al₂O₃ which was not prepared by others and put it...