The silica gel column of Jiangyin Chuangtong Chromatography Equipment Co., Ltd. is separated according to the different adsorption forces of the substance on silica gel. Under normal circumstances, the more polar substances are easily adsorbed by silica gel, and the less polar substances are not easily On silica gel adsorption, the entire chromatography process is adsorption, desorption, re-adsorption, and desorption.