盐碱地改造用高效阻盐材料的制备及其性能研究OA北大核心CSTPCD

In order to improve saline-alkali soil,a superhydrophobic particle material with an excellent waterproof and salt-blocking performance was prepared,which was used to build a saline-alkali soil reconstruction system with a water-storage mode.Substrate material and desert sand were modified with a hydrophobic coating.The influences of resin content and micro-/nano-material content on the hydrophobicity,impermeability and breathability of the material were studied.A self-designed mini soil-column was used to simulate the migration process of underground saline water,and the waterproof and salt-blocking properties of the prepared materials were explored.The results show that when resin,hydrophobic CaCO3 and nano-SiO2 contents were 1.0%,0.8%and 0.2%,respectively,the material achieved a water contact angle of 153.6°,a water-resistant height of 230 mm,and maintained a good air permeability.The mini soil-column simulation test indicates that the material has a strong inhibition effect on the water evaporation and the upward movement of salt,with an evaporation-inhibiting rate of 50%to 70%and a salt-blocking rate of more than 99%,which maintains 97.5%after 20 test cycles.