The photocatalytic degradation of methylparaben was investigated under simulated solar light using a synthesised metal–organic framework (UiO-66-NH₂). For that purpose, the pollutant was spiked in different water matrices: distilled water, water from Lima River (Northwestern Portugal), and urban wastewater. Complete removal of the methylparaben in distilled water was achieved in 1 h reaction. In natural water matrices, the photocatalytic performance decreased to 70% removal after 3 h reaction, owing to the physical–chemical properties of the water samples. The UiO-66-NH₂ photocatalyst revealed high stability under the continuous mode, reaching a steady state in 5 h, from which the removal percentage was kept constant for 25 h. The photocatalytic degradation of methylparaben gave five main reaction byproducts and four short-chain carboxylic acids, identified by LC/ESI-MS and UHPLC analyses, respectively. The mechanism of degradation was investigated by using selective scavengers. Photogenerated holes and superoxide radicals were found as the main species responsible for the degradation of methylparaben. The abatement of other parabens (as ethyl- and propylparaben) was also evaluated, being the conversion influenced by the length of the alkyl side chain. The results of this study give a comprehensive sight into the effective photocatalytic remediation of parabens using UiO-66-NH₂.

使用合成的金属-有机骨架（UiO-66-NH ₂）在模拟太阳光下研究了对羟基苯甲酸甲酯的光催化降解。为此，污染物被添加到不同的水基质中：蒸馏水、利马河（葡萄牙西北部）的水和城市废水。在 1 小时反应中实现了蒸馏水中对羟基苯甲酸甲酯的完全去除。在天然水基质中，由于水样的物理化学性质，光催化性能在反应 3 小时后降低至 70%。UiO-66-NH ₂光催化剂在连续模式下表现出较高的稳定性，在 5 小时内达到稳定状态，去除率在 25 小时内保持恒定。对羟基苯甲酸甲酯的光催化降解产生了五种主要反应副产物和四种短链羧酸，分别通过 LC/ESI-MS 和 UHPLC 分析鉴定。通过使用选择性清除剂研究降解机制。发现光生空穴和超氧自由基是对羟基苯甲酸甲酯降解的主要物质。还评估了其他对羟基苯甲酸酯（如对羟基苯甲酸乙酯和对羟基苯甲酸丙酯）的减少，这是受烷基侧链长度影响的转化率。本研究结果全面介绍了使用 UiO-66-NH _{2对羟基苯甲酸酯的有效光催化修复}.