Study On Controllable Synthesis And Growth Mechanism Of Potassium Titanate Crystal

Potassium titanate crystal has been widely studied due to a series of excellent properties. It has numerous variants, among which potassium tetratitanate and potassium hexatitanate possess relative high application value. In addition, potassium titanate was reported to have a variety of morphologies, such as whiskers, flakes, particles and so forth. Studies have always been concentrated on potassium hexatitanate whiskers in these years, while studies about other variants and morphologies received less attention.Therefore, the Kneading-Drying-Calcination(KDC) method which is suitable for industrialized production was adopted to synthesize potassium titanate crystal. The influence of various factors on the phase composition and micromorphology of potassium titanate crystal were discussed successively by orthogonal design and single variable method, thus achieved their controllable synthesis.The microstructure of potassium titanate crystal was analyzed by a series of methods,including XRD, SEM, EDS. Results show that Ti O2/K2CO3 molar ratio(T/K ratio) and calcination temperature have great influence on phase composition of potassium titanate.The optimal T/K ratio of synthesizing high purity potassium tetratitanate and potassium hexatitanate are 3.0 and 5.0, respectively. While the optimal T/K ratio was fixed, the effects of calcination temperature, holding time, cooling rate, and heating rate on the morphology of potassium titanate decrease successively. After gradual discussion, the temperature, holding time, and heating rate turning point of the optimal potassium tetratitanate whiskers and particles, potassium hexatitanate whiskers and particles turn out to be: 1050℃, 1.5h, 800℃; 850℃, 3h, 800℃; 1100℃, 1h, 800℃; 800℃, 2h, 600℃.Above samples were cooled in the furnace and only the raw material of potassium tetratitanate particles was treated by tablet processing. On the basis of a large amount of experimental results, the growth mechanism of potassium titanate crystal synthesized by KDC method was summarized as concatenation-parallel growth.