Graphs from the modification of the hydroxyl surface of potassium acetate intercalcated halloysite between 25 and 300 degrees celcius

Halloysite from Szeg, Hungary was analyzed for phase purity using X-ray diffraction techniques. The halloysite was purified by sedimentation and size fractionated to <20 μm. Three hundred milligrams were treated with 30 cm3 of 7.2 M potassium acetate solution. The sample was shaken for 80 hours in a constant temperature bath at ambient temperature. The excess solution on the clay was removed by centrifugation. The potassium acetate-intercalated halloysite was allowed to dry in air before analysis.

Figure 1 shows X-ray diffraction patterns of potassium acetate-intercalated halloysite heated to 250 °C and cooled to 25 °C under nitrogen. Figure 2 is a graph showing crystallite size as a function of temperature upon heating and cooling. Figure 3 is Raman spectra of the hydroxyl-stretching region of potassium acetate intercalated halloysite sequentially heated, as labeled. Figure 4 shows the variation of the peak position (a) bandwidth (b) of the hydroxyl-stretching bands of potassium acetate-intercalated halloysite as a function of temperature. Figure 5 shows Raman spectra of the hydroxyl deformation and C-C stretching region of potassium acetate-intercalated halloysite after heating to the prehydroxylation temperature and cooling to 25 °C. Figure 6 is Raman spectra of the hydroxyl deformation and C-O stretching region of potassium acetate-intercalated halloysite after heating to the prehydroxylation temperature and cooling to 25 °C. Figure 7 shows the variation of the relative intensities of the two CO2− symmetric stretching modes and the two acetate bonded inner surface hydroxyl stretching vibrations as a function of temperature. Figure 8 Raman spectra of the OCO bending region of potassium acetate-intercalated halloysite after heating to the predehydroxylation temperature and cooling to 25 °C.

匈牙利塞格的蛭石经X射线衍射技术分析其相纯度。通过沉降法进行提纯，并按粒径分级至小于20微米。取300毫克样品，与30立方厘米的7.2摩尔乙酸钾溶液混合。在室温下，样品在恒温水浴中振荡80小时。通过离心法去除粘土上的多余溶液。在分析前，将乙酸钾插层蛭石置于空气中干燥。图1展示了在氮气环境下加热至250摄氏度并冷却至25摄氏度后的乙酸钾插层蛭石的X射线衍射图案。图2为加热和冷却过程中晶粒尺寸随温度变化的图表。图3为按标记顺序加热的乙酸钾插层蛭石羟基伸缩区的拉曼光谱。图4展示了乙酸钾插层蛭石羟基伸缩带峰位（a）带宽（b）随温度变化的规律。图5展示了在预羟基化温度加热并冷却至25摄氏度后的乙酸钾插层蛭石羟基变形和C-C伸缩区的拉曼光谱。图6为在预羟基化温度加热并冷却至25摄氏度后的乙酸钾插层蛭石羟基变形和C-O伸缩区的拉曼光谱。图7展示了两种CO2对称伸缩模式和两种乙酸键合内表面羟基伸缩振动相对强度随温度变化的规律。图8为在预脱羟基化温度加热并冷却至25摄氏度后的乙酸钾插层蛭石OCO弯曲区的拉曼光谱。