Figure 1
From: A multifunctional azobenzene-based polymeric adsorbent for effective water remediation
A multifunctional azobenzene (AZ)-based polymeric adsorbent SiO2@PEI@AZ/PEG on the basis of multiple interactions for effective simultaneous removal of trace carcinogenic polycyclic aromatic hydrocarbons (PAHs) and anionic dyes in water.
(i) Acid-catalyzed silanol condensation; (ii) and (iii) oxirane-amine coupling (PEI has 232 repeat units on average but only several are shown here for clarity). The polycyclic aromatic hydrocarbons (PAHs) in the polluted water can be removed based on the hydrophobic effect and π–π stacking with AZ moieties, whereas the anionic dyes can be simultaneously removed by electrostatic interaction and van de Waals forces with PEI. The collected pollutants can be easily removed by washing with chloroform/aqueous NaOH solution and thus the adsorbent is recycled.
