摘要
本文利用溶液法制备了K_(2)Ba[B_(4)O_(5)(OH)_(4)]_(2)·8H_(2)O,并将其进行热处理制备得到了KBaB_(5)O_(9),利用XRD、FT-IR、TG-DTA-DTG对样品进行了表征。分析研究了由K_(2)Ba[B_(4)O_(5)(OH)_(4)]_(2)·8H_(2)O热处理制备KBaB_(5)O_(9)过程中的物相变化过程,其物相变化经历脱结晶水、脱羟基、重结晶、再分解、熔融再结晶5个阶段,其中结晶水的脱失分两步进行。运用Kissinger法、Flynn-Wall-Ozawa法、atava-est k法对K_(2)Ba[B_(4)O_(5)(OH)_(4)]_(2)·8H_(2)O结晶水第二步脱失过程的动力学参数进行了计算,可知K_(2)Ba[B_(4)O_(5)(OH)_(4)]_(2)·8H_(2)O结晶水第二步脱失过程的活化能E_(s)为151.94 kJ/mol,指前因子的对数值lg A_(s)为21.25 min^(-1),机理函数G(α)=(1-2α/3)-(1-α)^(2/3)(其中α为转化率)。
In this paper,K_(2)Ba[B_(4)O_(5)(OH)_(4)]_(2)·8H_(2)O was prepared by solution method,and KBaB_(5)O_(9)was prepared by heat treatment of K_(2)Ba[B_(4)O_(5)(OH)_(4)]_(2)·8H_(2)O.The samples were characterized by XRD,FT-IR,and TG-DTA-DTG.The phase change process in the preparation of KBaB_(5)O_(9)by heat treatment of K_(2)Ba[B_(4)O_(5)(OH)_(4)]_(2)·8H_(2)O was analyzed and studied.The phase change experiences five stages:the loss of crystal water,the loss of hydroxyl,recrystallization,redecomposition,and recrystallization after melting.The loss of crystal water is divided into two steps.The kinetic parameters of the second step loss process of crystal water in K_(2)Ba[B_(4)O_(5)(OH)_(4)]_(2)·8H_(2)O were calculated by Kissinger method,Flynn-Wall-Ozawa method,and atava-est k method.The activation energy E_(s)of the second-step loss process of crystal water in K_(2)Ba[B_(4)O_(5)(OH)_(4)]_(2)·8H_(2)O is 151.94 kJ/mol,the logarithm of pre-exponential factor lg A_(s)is 21.25 min^(-1),and the mechanism function is G(α)=(1-2α/3)-(1-α)^(2/3)(αis conversion rate).
作者
全志林
李志祥
焦斌
周贤委
向德兴
冯晓琴
黄宏升
QUAN Zhilin;LI Zhixiang;JIAO Bin;ZHOU Xianwei;XIANG Dexing;FENG Xiaoqin;HUANG Hongsheng(School of Chemical Engineering,Guizhou Institute of Technology,Guiyang 550003,China;Key Laboratory of Energy Chemistry for General Higher Education in Guizhou Province,Guiyang 550003,China)
出处
《硅酸盐通报》
CAS
北大核心
2022年第8期2954-2962,共9页
Bulletin of the Chinese Ceramic Society
基金
国家自然科学基金(21963006)
贵州理工学院高层次人才科研启动项目(XJGC2019614)
国家级大学生创新创业训练项目(202114440030)。
关键词
多金属硼酸盐
硼酸钾钡
湿化学法
热分解
动力学
活化能
polymetallic borate
potassium borate barium
wet chemical method
thermal decomposition
kinetics
activation energy
