The Preparation of an Ion-Imprinted Polymer Based on Hyperbranched Polyamide-Amines and Epoxy Resin and Its Efficient Adsorption Mechanism for Cr(VI) from Aqueous Solutions

Cr(VI) is listed as the first category pollutant that needs strict control, posing a lasting risk to the environment and human body. Ion imprinting technology has attracted more and more researchers' attention due to its high selectivity. Here, a chromium(VI)-imprinted polymer (Cr(VI)-IIPs) was prepared by precipitation polymerization using potassium dichromate (K 2 Cr 2 O 7 ) as the template ions, tert-butanol [C(CH 3 ) 3 OH] as a pore-forming agent, Bisphenol A epoxy resins as the carrier, and hyperbranched polyamide-amines as curing and complexing agent. The research objective of this work is to crosslink epoxy resin as a matrix with hyperbranched polyamides to obtain ion imprinted materials with stable structure, acid and alkali resistance, low cost, and reusability. The detailed adsorption studies reveal that the adsorption behavior of the Cr(VI)-IIPs for Cr(VI) conforms to the quasi-second-order kinetic model and Langmuir adsorption isotherm model. At pH = 2 and 298K, the theoretical maximum adsorption capacity reached 263.15mg/g, reaching adsorption equilibrium within 120 min. Moreover, the adsorbent can be regenerated and the equilibrium adsorption amount will not decrease significantly. In addition, the column adsorption experiment shows that Cr(VI)-IIPs can be well applied to the treatment of actual wastewater.