| Layered phosphates have been received considerable amount of attention dueto their potential application in the fields of catalysis, sorption and protonicconduction. Focus studied is novel synthesis method and correlative propertiesabout layered polyvalent metal phosphates. Therefor, in this paper, nanometercrystalline Zr(HPO4)2·H2O,NaSn2(PO4)3 and NH4ZrH(PO4)2·H2O weresynthesized via solid-state reaction at low heat respectively. Besides, thermaldecomposition kinetics and catalytic performance of NH4ZrH(PO4)2·H2O usedin synthesis of butyl acetate were investigated. The paper consists of fivechapters.Chapter one: Preparation via solid-state reaction at low heat and characterizationof Zr(HPO4)2·H2OThe layered nanometer crystalline Zr(HPO4)2·H2O was obtained whenZrOCl2·8H2O and (NH4)3PO4·3H2O were fully ground via solid-state reaction at room temperature, then mixture was heated at 80C for 96 h, and washed withwater to remove soluble inorganic salts and dried at 80℃. Product and itsthermal decomposition products were characterized by TG/DTA,IR and XRD.The results showed that average particle size of nanometer crystallineZr(HPO4)2·H2O obtained at 80℃was about 23 nm, with high crystallization,space group P21/c(14). Its crystal structure can stabilize until 450C. WhenZr(HPO4)2·H2O was calcined at 900℃for 3h, the nanometer crystalline ZrP2O7with high crystallization, space group Pa-3(205), was obtained, and its averageparticle size was about 31 nm.Chapter two: Preparation via solid-state reaction and characterization ofNaSn2(PO4)3Precursor of nanometer crystalline NaSn2(PO4)3 was obtained whenNa2HPO4·12H2O and SnCl4·5H2O were fully ground via solid-state reaction atroom temperature, then mixture was heated at 80℃for 2h, and washed withwater to remove soluble inorganic salts and dried at 80℃. Nanometer crystallineNaSn2(PO4)3 with high purity was obtained by thermal crystallization ofprecursor at 600℃for 1h. Precursor and product were characterized byTG/DTA, IR, XRD and SEM. The results show that average particle size ofnanometer crystalline NaSn2(PO4)3 was about 49.6 nm, Space group R-3 (148),obtained at 600℃for 1h.Chapter three: Preparation via solid-state reaction at low heat andcharacterization of NH4ZrH(PO4)2·H2O Nanocrystalline NH4ZrH(PO4)2·H2O was obtained when ZrOCl2·8H2O and(NH4)2HPO4 were fully ground via solid-state reaction at room temperature,then mixture was kept at 80℃to change amorphous NH4ZrH(PO4)2 into crystal,washed with water to remove soluble inorganic salts and dried at 80℃. Productand its product of thermal decomposition were characterized by TG/DTA, IRand XRD. Result showed that nanocrystalline NH4ZrH(PO4)2·H2O, with averageparticle size of 17 nm, was obtained when product was kept at 80℃for 48h,and its crystalline framework can keep until 250℃.Chapter four: Study on thermal decomposition kinetics of NH4ZrH(PO4)2·H2OThermal decomposition kinetics of NH4ZrH(PO4)2·H2O was studied bythermo-gravimetric-differential thermal analysis (TG-DTA). The results showedthat thermal decomposition of NH4ZrH(PO4)2·H2O at temperatures below 700℃occurs in three well-defined steps. Activation energy (E), frequency (A) andmechanism function of each thermal decomposition reaction step as follows: Eis 50.78 kJ/mol, ln(A) is 11.13～12.54 and g(α) is [(1-α)-1/3-1]2 for reaction(1);E is 104.13 kJ/mol, 1n(A) is 11.03～12.38 and g(α) isα2 for reaction(2); E is117.04 kJ/mol, 1n(A) is 11.78～12.93 and g(α) is (1-α)-2 for reaction(3).Chapter five: Catalytic performance and mechanism of NH4ZrH(PO4)2·H2O forsynthesis of butyl acetateButyl acetate was synthesized when acetic acid and butanol were used asraw materials and NH4ZrH(PO4)2·H2O was used as catalyst. The optimumconditions were obtained via orthogonal experiment method. The result showed that the optimum conditions were as follows: molar ratio of n-butanolto acetic acid was 1:1.92, consumpution of catalyst and n-butanol were 1.50 gand 0.109mol respectively, reaction time was 5.5 h, and esterification percentwas 99.4％under the optimum conditions. Moreover, catalytic mechanism ofNH4ZrH(PO4)2·H2O used in synthesis of butyl acetate was investigated.
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