Study On The Synthesis Of Nopol And Nopyl Acetate By Solid Superacid

Preparation of solid superacids and its application in the synthesis of Nopol and Nopyl acetate were investigated in this paper.The preparation conditions of catalysts SO₄^2-/ZrO₂ and SO₄^2-/TiO₂-ZrO₂ and the reaction conditions of Nopol and Nopyl acetate were discussed. Meanwhile, the solid superacid acidity was determined by flowing Hammett indicator, and the affecting factors were also discussed.The suitable preparation conditions of SO₄^2-/ZrO₂ catalyst with the maximum acidity were: being treated with H₂SO₄ concentration at 0.5～1.0mol/L, calcination temperature at 550～700℃. While the suitable preparation conditions of SO₄^2-/TiO₂-ZrO₂ were: calcination temperature was 450～650℃, and H₂SO₄ concentration at 1.0mol/L. FTIR analysis was employed to characterize the structures of SO₄^2-/ZrO₂ and SO₄^2-/TiO₂-ZrO₂.Through various single factors analysis and orthogonal experiments, the optimum technology combination was determined.The yield of Nopol by the heating method reached 64.3%, with SO₄^2-/ZrO₂ as the catalyst, calcination temperature 600℃, reaction temperature 120℃for 10h, catalyst amount 4.5%(based on total material weight), and the 1:1.05 molar ratio of paraformal toβ-pinene.The yield of Nopol by microwave irradiation method achieved 67.7%, with SO₄^2-/ZrO₂ as the catalyst, calcination temperature 600℃, irradiation power 660W, irradiation temperature 95℃for 130 minutes, catalyst amount 4%(based on total material weight), and the 1:1.05 molar ratio of paraformal toβ-pinene.The yield of nopyl acetate by the heating method reached 74.3%, with SO₄^2-/TiO₂-ZrO₂ as the catalyst, the 4:1 molar ratio of Ti to Zr, calcination temperature 550℃, catalyst amount 3%(based on nopol weight), reaction time 5.0h, and the 1:1.15 molar ratio of Nopol to acetic acid. The yield of nopyl acetate by microwave irradiation method achieved 81.3%, with SO₄^2-/TiO₂-ZrO₂ as the catalyst, the 6:1 molar ratio of Ti to Zr, calcination temperature 450℃, catalyst amount 2.5%(based on nopol weight), irradiation power 650W, irradiation temperature 105℃for 85 minutes, and the1:1.15 molar ratio of Nopol to acetic acid.Spectrum and Gas chromatogram-Mass Spectrum were used to determine the structure of the resulting products.The regeneration of catalyst was also examined in this paper. This research paves way for the application of SO₄^2-/M_xO_y types solid superacid in deeply processing ofβ-pinene to some extent.