论文总字数：18365字

摘 要

本文首先综述了有关杂多化合物的含义、分类、性质、制备方法和应用。钨硼酸盐是经典的杂多化合物之一，在催化、医药等多方面有广泛的应用。

论文主要探讨pH值对钨硼酸钾合成的影响。实验采用新制钨硼酸和氯化钾反应，通过改变其反应pH值（pH值分别为5.5，5.9，6.3，6.7和7.1），保持其他条件完全相同的情况下，合成硼钨酸钾。然后通过电导率仪、红外、紫外光谱仪和X射线衍射仪对产物性质进行表征，比较、分析不同pH值对硼钨酸钾的产量及其性质的影响。

实验结果表明：在pH= 5.5~7.1的范围内都能得到11-钨硼酸钾，产物的产率随pH值的升高而降低，pH值对产物的电导率影响不大。综合考虑产物的产率、纯度和结晶度性能，pH=6.3是制备11-钨硼酸钾最适宜的酸度条件。

关键词：pH值 钨硼酸钾 产率 红外光谱 X射线衍射

Effects of pH value on Synthesis of boron potassium tungstate

Abstract

In this paper, the definition, classification, properties, preparation methods and application of the heteropoly compounds are firstly summarized. Boron tungstate is one of the classical compounds and has been widely used in Catalysis, Medicine and so on.

The influence of pH value on synthesis of boron potassium tungstate is discussed in this paper. The synthesis of boron potassium tungstate by new tungsten borate and potassium chloride is carried out under the acidity condition was artificially altered (pH=5.5, 5.9, 6.3, 6.7 and 7.1, respectively) and other conditions remaining unchanged. Then its properties were characterized by Conductivity meter, IR, UV spectroscopy and X - ray diffraction, spectra measured at different pH values of boron potassium tungstate synthesis conditions, comparing the effect of different pH value on the yield and properties of boron potassium tungstate.

The results show that the yield of 11- tungsten borate can be obtained from the range of pH= 5.5 ~ 7.1, the yield is inversely proportional to pH value and the pH value had little effect on the conductivity of the electric conductivity. Based on comprehensive consideration of the yield, purity and crystallinity of the product, the optimum acidity condition for preparation of 11- tungsten potassium borate was pH=6.3.

Key Words:The value of pH;Boron potassium tungstate;yield;Infrared spectrum;

X-ray Diffraction

目 录

摘要…………………………………………………………………………………I

ABSTRACT………………………………………………………………………II

第一章 绪论………………………………………………………………………1

1.1 引言………………………………………………………………………1

1.1.1 杂多化合物的含义………………………………………………1

1.1.2 杂多化合物的分类………………………………………………1

1.1.3 杂多化合物的性质………………………………………………4

1.1.4 杂多化合物的制备方法…………………………………………6

1.1.5 杂多化合物的应用………………………………………………8

1.2 选题思路和拟采用的研究手段…………………………………………9

1.2.1 选题思路…………………………………………………………9

1.2.2 拟采用的研究手段………………………………………………10

第二章 实验………………………………………………………………………11

2.1 实验试剂与仪器…………………………………………………………11

2.1.1 实验试剂…………………………………………………………11

2.1.2 实验仪器…………………………………………………………11

2.2 实验步骤…………………………………………………………………12

2.3 实验表征相关原理………………………………………………………12

2.3.1 红外光谱仪………………………………………………………12

2.3.2 X射线晶体衍射…………………………………………………12

2.3.3 紫外分光光度法…………………………………………………13

2.3.4 电导率……………………………………………………………13

第三章 实验结果与讨论………………………………………………………15

3.1 引言………………………………………………………………………15

3.2 不同pH值制得产物的产率……………………………………………15

3.3 不同pH值制得产物的FT-IR图………………………………………15

3.4 不同pH值制得产物的电导率表征……………………………………16

3.4.1 电导率定义……………………………………………………16

3.4.2 不同pH值下合成的11-钨硼酸钾的电导率…………………17

3.5 不同pH值制得产物的XRD图………………………………………17

3.5 11-钨硼酸钾的紫外-可见光光谱表征…………………………………19

第四章 结论与展望……………………………………………………………20

4.1 实验结论………………………………………………………………20

4.2 展望……………………………………………………………………20

参考文献…………………………………………………………………………22

致谢………………………………………………………………………………24

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