On the basis of the method used by Reinsch and Solovyeva, the aluminum based MOF material CAU-10-H (CAU stand for Christian-Albrechts-University) was synthesized by multiplying the amount of aluminum sulfate octahydrate and isophthalic acid by 10 times. CAU-10-H (b) is obtained after washing. In order to improve the water vapor adsorption performance of pure CAU-10-H (b), lithium chloride (LiCl) solution was compounded with CAU-10-H (b) by impregnation method to obtain a composite adsorbent CAU-10-H (L) and its adsorption characteristics were studied. The results showed that the composite adsorbent showed good adsorption and desorption performance under test conditions. Among them, the equilibrium adsorption capacity of the composite adsorbent with 33.1% LiCl content is 0.5007 g/g after 30 cycles, which is about 1.675 times of the adsorption capacity of pure CAU-10-H (b) under the same conditions. This shows the potential of the composite adsorbent to be used in the air-water extraction system. In this paper, aluminum based MOF material CAU-10-H Al (OH) (m-BDC) 2, CAU stand for Christian Albrechts University was synthesized. The performance test proves the performance advantage of CAU-10-H (b). In order to improve the adsorption performance of the adsorbent, the composite adsorbent CAU-10-H (L) was synthesized by impregnation. The composite adsorbent showed good desorption performance. This demonstrates the potential of the composite adsorbent for use in air-water extraction systems. Display omitted •Aluminum based MOF: CAU-10-H (CAU stand for Christian-Albrechts-University) was prepared by solvothermal synthesis using aluminum sulfate octahydrate and isophthalic acid as raw materials.•The sample of CAU-10-H after washing is named CAU-10-H (b). The microstructure characterization and open adsorption performance tests were done for CAU-10-H(b).•In order to improve the water vapor adsorption performance of CAU-10-H (b), a composite adsorbent CAU-10-H (L) was synthesized by impregnating CAU-10-H (b) with lithium chloride (LiCl) solution.•The water vapor adsorption capacity of the composite adsorbent is higher than that of CAU-10-H (b). The equilibrium adsorption capacity of the composite adsorbent with a mass fraction of 33.1% LiCl is about 1.675 times that of CAU-10-H (b).•The composite adsorbent has good desorption performance, high desorption rate, low desorption temperature, and can reduce energy consumption in practical application.