Chloride-induced reinforcement corrosion in marine concrete structures adversely impacts its durability, which leads to the decrease of the actual service life of concrete. Three kinds of layered double hydroxides (LDHs), CaFe–NO₃ LDHs (LDHs-CF), CaAl–NO₃ LDHs (LDHs-CA) and CaFeAl–NO₃ LDHs (LDHs-CFA), were synthesized to bind chloride. The results showed that all of the synthetized LDHs could effectively adsorb chloride from simulated concrete pore solutions (SCPSs) and artificial seawater (ASW) through the surface adsorption and ion exchange. The maximum chloride adsorption capacity of the LDHs-CFA was 3.18 mmol g⁻¹. The adsorption process could be described by the Langmuir isotherm and pseudo-second-order kinetic models. For the chloride desorption experiments, the chloride desorption rate of the LDHs-CF (29.20%) and LDHs-CFA (39.31%) were lower than that of the LDHs-CA (47.45%), because the presence of Fe³⁺ in LDHs suppressed the concentration of dissolved metals, and a crystal transformation occurred to form 3CaO·Fe₂O₃·0.5CaSO₄·0.5CaCl₂·10H₂O, exhibiting excellent stability for LDHs-CF and LDHs-CFA. In conclusion, LDHs show excellent chloride binding behaviour, which makes it promising to achieve the goal of high efficiency and stability of chloride binding for marine concrete by LDHs.

氯化物在船用混凝土结构中引起的钢筋腐蚀对其耐久性产生不利影响，从而导致混凝土的实际使用寿命降低。合成了三种层状双氢氧化物（LDHs），CaFe–NO ₃ LDH（LDHs-CF），CaAl–NO ₃ LDH（LDHs-CA）和CaFeAl–NO ₃ LDH（LDHs-CFA）。结果表明，所有合成的LDHs都可以通过表面吸附和离子交换有效地吸附模拟混凝土孔隙溶液（SCPSs）和人造海水（ASW）中的氯化物。LDHs-CFA的最大氯吸附容量为3.18 mmol g ^-1。吸附过程可以用Langmuir等温线和伪二级动力学模型来描述。对于氯离子解吸实验，LDHs-CF（29.20％）和LDHs-CFA（39.31％）的氯离子解吸率低于LDHs-CA（47.45％），因为LDHs中存在Fe ³⁺。抑制了溶解金属的浓度，并发生了晶体转化，形成了3CaO·Fe ₂ O ₃ ·0.5CaSO ₄ ·0.5CaCl ₂ ·10H ₂ O，对LDHs-CF和LDHs-CFA表现出优异的稳定性。总之，LDHs具有优异的氯离子结合性能，这有望实现LDHs对海工混凝土的氯离子结合的高效和稳定的目标。