Preparation Of Solid Superacid By Microemulsion System And Its Application In Rosin Esterification

Solid superacid has many advantages such as high activity,no pollution etal than traditional acid catalyst. Thus,research on solid superacid has drawn more and more attention in industrial catalyst field. Up to now,the main problems of solid superacid:①The low total amount of acid.That is,Although the acid strength of catalyst was great, but the number of active sites per unit mass of catalyst is low, so too large amount of catalyst was used when reaction was doing, product cost was increased②The problem of catalyst stability. Namely, the main active component sulfur lost easily in the application. Especially in the higher temperature conditions.The main examination in this paper is that①the effect on catalytic property of solid superacid prepared by microemulsion method or soft template method,.②with the catalyst prepared by microemulsion method or the soft template agent method, catalyst was modified by rare earth, stability of catalyst was enhanced.③the composite solid superacid S₂O₈^2-/ ZnSO₄-SnO₂ and S₂O₈^2- / ZnSO4-TiO2 were prepared by microemulsion system, the cost of catalyst preparation was reduced significantly . And S₂O₈^2-/ ZnSO₄-SnO₂ was used to synthesize rosin glycerin ester,the results showed excellent activity.The main results are summarized as follows:（1） The solid superacid SO₄^2-/SnO₂ was prepared in AEO-3 solft template agent system. As AEO-3 used ,an influence was produced on the growth and arrangement of grain. the activity of the catalyst increased, and covalent of S = O on the catalyst was enhanced, thereby the super acid properties of catalyst was strengthened; the solft template agent method is better than Preparation of traditional water system;Optimal conditions of catalyst prepared: R （VH2O︰VAEO-3 + n-butanol） = 23︰50,aging time 36 h, concentration of H₂SO₄ 3.0 mol / L, calcination temperature 550℃, calcining time 3 h.（2） The rare earth solid superacid SO₄^2-/CeO₂-SnO₂ was prepared in SDBS solft template agent system. The activity and stability of catalyst were improved as growth direction and arrangement form of catalyst grains in environment of SDBS solft template agent system; The optimum conditions for the preparation of solid superacid SO₄^2-/SnO₂-CeO₂ are concentration of SnCl4 0.1 mol/L, mass ratio between solution and SDBS 250︰1, volume ratio between ethylene glycol and solution 1︰4,aging time 24 h, content of Ce（SO₄）₂·4H₂O 6%（relative SnO₂）,concentration of impregnating solution 3 mol/L, calcining temperature 550℃and calcining time 3 h. the method is superior than the sol-gel method used early at the preparation of rare earth solid superacid SO₄^2-/CeO₂ -SnO₂（3） The rare earth solid superacid SO₄^2-/ SnO₂-Nd₂O₃ was prepared in SDBS solft template agent system.. Rare earth oxide Nd₂O₃ can delay crystalline and stabilize SO₄^2- of catalyst, so that it becomes more difficult that SO₄^2- drained. Namely, the stability of catalyst modified by rare earth has been improved; the amount of activity size of catalyst prepared by SDBS solft template agent system was increased,because the growth direction of grain and morphology of catalyst partical were regulated in the environment that SDBS is used;The optimum conditions for the preparation of solid superacid SO₄^2-/SnO₂-Nd₂O₃ are concentration of SnCl4 0.1 mol/L, mass ratio between solution and SDBS 500︰1, aging time 24 h, content of Nd₂O₃ 4%（relative SnO₂）,concentration of impregnating solution 3 mol/L, calcining temperature 550℃and calcining time 3.0 h.（4） A new type of solid superacid catalyst SO₄^2-/SnO₂-Ta₂O₅ was prepared by O/W microemulsion method in SDBS/ethanol/cyclohexane system. the morphology and row of grain were changed in O/W microemulsion system,and a strong inductive effect was appeared on the electron cloud of the Sn,the activity and stability of catalyst were enhanced as the two influences; The optimum conditions for the preparation of solid superacid SO₄^2-/SnO₂-Ta₂O₅ are concentration of SnCl4 0.1 mol/L,mass ratio between solution,SDBS, ethanol and cyclohexane 500︰1︰0.5︰15, content of Ta₂O₅ 8%, aging time 12 h,concentration of im- pregnating solution 3 mol/L, calcining temperature 550℃and calcining time 3 h.（5） A new type of rare earth solid superacid catalyst Ce⁴⁺-SO₄^2-/SnO₂-Nd₂O₃ was prepared by microemulsion method in OP-10/n-butanol/cyclohexane system. Ce⁴⁺, Nd₂O₃ could delay crystallization, and made the loss amount of active components lower in the time of reaction,so the stability of the catalyst was improved; microemulsion system could guarantee effectively the catalyst with larger BET, so the catalyst has a high acid content that prepared by microemulsion method; The optimum conditions for the preparation of solid superacid Ce⁴⁺-SO₄^2-/SnO₂-Nd₂O₃ are mass ratio between surfactant and solution 65︰ 100, content of Ce（SO4）2·4H2O 8%, content of Nd₂O₃8%, aging time 12 h,concentration of impregnating solution 3 mol/L, calcining temperature 550℃and calcining time 3 h.（6） S₂O₈^2-/ZnSO₄-SnO₂ was prepared by microemulsion method and it was applied to synthesis the rosin glycerine ester. The optimal preparation conditions of solid superacid S₂O₈^2-/ ZnSO₄-SnO₂︰R = 100︰50, mSnO₂/mZnO = 30︰100, aging time 24 h, impregnatal concentration 2.0 mol/L, calcination temperature 550℃, calcination time 3.0 h; the matrix crystal of the catalyst is monoclinic ZnSO₄!?H₂O; the active component was combined to metal bridging connection, the mass fraction of it is approximately 8.333%; microemulsion system is superior than conventional water system in the capacity of combination the active component; catalysts was applied to the synthesis rosin glycerine ester, the reaction temperature is reducd about 40℃, the softening point is higher than the national standard 6℃, reaction time was shortened to 4 h, the remaining indicators are meet the national standard GB 10287-88, the catalyst have better prospects for the synthesis rosin glycerine ester.（7） S₂O₈^2-/ZnSO₄-TiO₂ was prepared by microemulsion method . The optimal preparation conditions of solid superacid S₂O₈^2-/ ZnSO₄-TiO₂︰R = 100︰50, mSnO₂/m ZnO=30︰100, aging time 24 h, the impregnating concentration 2.0 mol/L, calcination temperature 400℃; catalyst grain contain a variety of crystal structure （the main crystal is monoclinic ZnSO₄!?H₂O）, the acid amount of catalyst is the largest, and the activity of catalyst is the highest in their synergy;the impregnatal concentration would impact the proportion of the crystal and their synergies; so it shouldn’t be higher or lower;microemulsion system is favorable to the improvement of catalyst activity,catalyst had a better cavity structure prepared by microemulsion system, so it was superior to conventional water system.（8） The effect of OP-10 microemulsion method and soft template agent of AEO-3 and SDBS method on performance of catalyst. In the microemulsion system,the growth of grain was limited ,the phoenomenon of secondly reunion was inhibited effectively ,the catalyst morphology could be controled , that the acid amount of catalyst was increasedand,the catalyst stability was enhenced, the catalyst activity was improved. So OP-10 microemulsion system is superior than soft template agent system on the preparation of the catalyst; anionic surfactant SDBS as a template agent not only can prevent particles grow up and make the catalyst has a certain appearance, but could change the grain preferred orientation and affect the formation of nuclei, so that the catalyst acid strength enhenced, and the amount of acid increased; the optimizing order of the three kinds of preparation system were: OP-10 microemulsion system, anionic surfactant SDBS as a template agent system, the non-ionic surfactant AEO-3 as a template agent.