3.2.2. Scanning electron microscopy
Fig. 4(a) and (b) show 6000X magnification scanning electron microscopy (SEM) images of bentonite and bentonite loaded with potassium sorbate. Fig. 5(a) and (b) show the respective SEM spectrum diagrams. Fig. 4 shows that the structures of these two materials were layer slices, a typical characteristic of bentonite. It can be seen from the figure that the structure of bentonite was not destroyed after loading with the potassium sorbate. This indicated that there was no chemical change caused by the loading process. This conclusion is in accordance with the XRD findings. Fig. 5 illustrates that there were no obvious differences in the contents of elements like aluminum, silicon, and oxygen after loading with potassium sorbate, which could indicate montmorillonite content of bentonite. The potassium content of bentonite loaded with potassium sorbate was obviously higher than without loading, which indicates that the potassium sorbate was absorbed by the bentonite.