A novel GO/PNIPAm hybrid with two functional domains can simultaneously effectively adsorb and recover valuable organic and inorganic resources

Competing for adsorption active sites decrease the efficiency of simultaneous adsorption of co-existent adsorbates. On the other hand, different adsorbates being desorbed at the same eluting condition will cause they are mixed together after the desorption, and ruin the recovery. Aim at these problems, a novel adsorbent with two functional domains was designed in this study. This adsorbent is a nano hybrid with two functional domains. One is GO domain which is responsible for the adsorption of inorganic metal ions; another is PNIPAm domain which is responsible for the adsorption of organic molecules. This two-function-domain structure can avoid organic and inorganic adsorbates to compete the same adsorption active sites. Pb2+ and 4-NP were taken as the model inorganic and organic adsorbates in this study. The locations of adsorbed Pb2+ and 4-NP were confirmed by the results of adsorption experiments, BET and XPS analysis. The structure of hybrid was studied by FTIR, Raman spectra and TGA analysis. The hybrid exhibits high adsorption capacity toward Pb2+ and 4-NP with high anti-inference ability. Furthermore, Pb2+ and 4-NP can be efficiently desorped one by one with acidic or alkalinous condition, respectively. So they will not be mixed together after the desorption, and can be sequentially recovered. Due to the high efficiency and easy operation, the hybrid is considered as a promising adsorbent to simultaneously adsorb and recover organic and inorganic resources, and the method reported here could provide a new thinking way to develop highly effective adsorbents.