K-phillipsite was prepared using a hydrothermal method.Soluble glass and sodium aluminate were used as raw materials in the absence of an organic template,investigations regarding the K~+ ions were conducted at room temperature to determine the ion-exchange capacity in the seawater sample and the selectivity coefficient of the mixed K~+-Na~+solution.The sample was characterized by X-ray diffraction(XRD),scanning electron microscopy(SEM),and energy dispersion spectroscopy(EDS).The K~+ ionexchange capacity is 51 mg/g in seawater and the selectivity coefficient is 75.1 in the mixed K~+-Na~+solution.The sample has a selectivity preference for K~+,and therefore can be used to selectively extract potassium from seawater.The sample composed of Si,Al,K,Na,and O exhibits a cross-like shape and is a typical K-phillipsite structure. K-phillipsite was prepared using a hydrothermal method .oluble glass and sodium aluminate were used as raw materials in the absence of an organic template, investigations regarding the K ~ + ions were conducted at room temperature to determine the ion-exchange capacity in the seawater sample and the selectivity coefficient of the mixed K ~ + -Na ~ + solution.The sample was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy dispersion spectroscopy (EDS) The capacity is 51 mg / g in seawater and the selectivity coefficient is 75.1 in the mixed K ~ + - Na ~ + solution. The sample has a selectivity preference for K ~ +, and therefore can be used to selectively extract potassium from seawater. sample composed of Si, Al, K, Na, and O exhibits a cross-like shape and is a typical K-phillipsite structure.