Phenylalanine-based low-molecular-weight gelator for the removal of metal ions and dyes from wastewater

Increasing water pollution is a major concern for the global community. So, purification and reuse of wastewater are very much urgent. In this work, methyl ester of phenylalanine (Phe-OMe), a non-gelator, has been successfully applied to produce two-component charge transfer–induced organogel and metallohydrogel using picryl chloride and Cu(II) respectively. These gels and their gelation processes were utilized to mop up different toxic metal ions and ionic dyes (especially zwitterionic dye) from wastewater. Phe-OMe can drop down these metal concentrations below the permissible limit of WHO within 10 min. Interestingly, the organogel instantly turns into sol upon the addition of either base or acid. This property makes the gel act as sensors of harmful acidic and basic vapors like HCl, ammonia, and so on in the laboratories and in different industries.

日益严峻的水体污染已成为全球社会共同关注的重大议题，因此废水的净化与回用已迫在眉睫。本研究中，非凝胶因子苯丙氨酸甲酯（methyl ester of phenylalanine，Phe-OMe）分别以苦基氯与Cu(II)为原料，成功制备出双组分电荷转移诱导型有机凝胶与金属水凝胶。上述凝胶及其凝胶化过程可用于去除废水中的多种有毒金属离子与离子型染料（尤其是两性离子染料）。Phe-OMe可在10分钟内将上述金属离子浓度降至世界卫生组织（WHO）规定的容许限值以下。值得注意的是，该有机凝胶在加入碱或酸后会迅速转变为溶胶，这一特性使得该凝胶可作为实验室与不同工业场景中有害酸碱蒸气（如氯化氢、氨气等）的检测传感器。