Changrong Zhao,Bin Liu,Senlin Shao,Bart Van der Bruggen
Flow-through catalytic membrane reactors aim to achieve a long-term safe and stable operation through the catalytic performance of the membrane itself. However, applications are hindered by the easy deactivation of catalytic sites and insufficient catalytic efficiency in complex aqueous environments and long-term operation. Here, a model is proposed that anchors Fe single atoms to the 2D material g-C 3 N 4 and combines it with a gravity-driven ultra-low-pressure filtration system to enhance the membrane catalytic performance and reduce the pollutant accumulation rate, respectively. In addition, Fe sites have a stronger adsorption energy for acetylaminophenol (APAP) and reactive oxygen species, thus increasing their contact in the filtration catalysis process. The efficient catalytic layer combined with the restricted space between the membranes endowed the membrane with a 100% APAP removal efficiency and a reaction rate of 0.225 m s −1 which is 5–7 orders of magnitude higher than conventional photocatalytic reactions. Even after ultra-long filtration time (100 h), 85% APAP removal and zero fouling accumulation can be achieved in real water samples. Compared with the reported technology, the pollutant degradation capacity of this work is improved by 3 orders of magnitude and almost negligible energy consumption. This system has nearly 100% degradation efficiency for various water pollutants and can be combined with other AOPs processes, revealing the importance of ultra-low-pressure filtration and the introduction of single atoms for mobile catalytic systems.
Development of a non-polluting process for cotton coloring is essential for the textile industry in view of ecological and economical reasons. In order to recycle the residual foam in the foam technique, a photo-responsive azobenzene cationic surfactant (4-butoxy-4′-(trimethylaminoethoxy)azobenzene, BTAEAzo) was synthesized for obtaining switchable foam based on its sensitive and reversible photo-isomerization capability. Trans → cis isomerization of BTAEAzo occurred only within 1 s UV light irradiation and cis → trans conversion could be achieved after 8 min visible light irradiation. Besides, BTAEAzo showed good thermal stability which was stable up to 225 °C. BTAEAzo was able to reversibly switch foam between the stable (t1/2 of 19.09 min) and unstable (t1/2 of 2.93 min) states by light stimulation. Furthermore, dye-bonded blocked waterborne polyurethane, a polymeric dye, was applied in the switchable system and showed no influence on the foam switching capability of BTAEAzo. The coated cotton presented superior color properties including the K/S value, color evenness and fastness with the switchable foam. Most importantly, the residual color foam can be re-used during the coating process with excellent color repeatability. These results demonstrated that the recycled foam coloring process containing only two types of chemicals is a rapid and nearly zero-pollution process, fostering a clean and green textile industry.
危险品化学品经营许可证（带存储）