Thermodynamic analysis for synthesis of aspirin catalyzed by aluminum tripolyphosphate / 中国生化药物杂志

Objective To explore the feasibility using aluminum tripolyphosphate as the synthesis of aspirin model instead of sulfuric acid catalyst. Methods The thermodynamic functions of the reaction system of salicylic acid and acetic anhydride were calculated according to the Benson group contribution method and Joback group contribution method.The enthalpy change,entropy and Gibbs free energy along with the change of temperature as well as the influence of the molar rate of reactants on the equilibrium conversation rate were also studied.Results In the temperature range of 298.15 K to 358.15 K,the reaction enthalpy was less than zero,and was exothermic reaction,and increase of temperature was not conducive to the reaction.The improvement of mole ratio of salicylic acid and acetic anhydride was helpful to improve the equilibrium conversation rate.The theoretical conversion rate could reach 99.58% when the mole ratio of salicylic acid and acetic anhydride was 3.Conclusion From the viewpoint of thermodynamics, the reaction is practical and feasible.

SYNTHESIS AND CHARACTERIZATION OF THE LAMELLAR MICROCRYSTALLINE ZINC PHOSPHATE α-Zn3 (PO4)2·4H2O / 药物分析学报

Objective To study the structural and anticorrosive property of microcrystalline α-Zn3 (PO4)2 ·4H2O. Methods Zinc phosphate was prepared from zinc acetate and orthophosphate acid in aqueous solution.Structural characteristics of products were investigated by XRD, RAMAN, FTIR, TG-DTA, SEM, surface area,particle size distribution, and density measurements. Results The title compound, a highly crystalline, micronized (A), c0 =5. 0304(A), V=975.86 (A)3. Its specific area is 0. 701 m2/g, density 3. 1612 g/m3 , and average size 4.75μm . Conclusion Comparing with commercial Zinc phosphate, the synthesized iamellar microcrystalline zinc phosphate had excellent anticorrosive property and dispersibility.

Synthesis and characterization of the lamellar microcrystalline zinc phosphate α-Zn3(PO4)2 · 4H 2O / 西安交通大学学报·英文版

Objective: To study the structural and anticorrosive property of microcrystalline α-Zn3 (PO4)2 · 4H2O. Methods: Zinc phosphate was prepared from zinc acetate and orthophosphate acid in aqueous solution. Structural characteristics of products were investigated by XRD, RAMAN, FTIR, TC-DTA, SEM, surface area, particle size distribution, and density measurements. Results: The title compound, a highly crystalline, micronized and lamellar α-Zn3 (PO 4)2 · 4H2O, has an orthorhombic monoclinic system, space group a0 = 10.597(Å),b0 = 18.308 (Å), c0 = 5.0304(Å), V = 975.86 Å3. Its specific area is 0.701 m2/g, density 3.1612 g/m3, and average size 4.75μm. Conclusion: Comparing with commercial Zinc phosphate, the synthesized lamellar microcrystalline zinc phosphate had excellent anticorrosive property and dispersibility.