Hierarchical macro and mesoporous foams synthesized by HIPEs template and interface grafted route for simultaneous removal of λ-cyhalothrin and copper ions

In this work, the hierarchical porous foams (HPFs) were fabricated and applied as the novel adsorbent for simultaneous removal of λ-cyhalothrin (LC) and Cu(II). Macroporous poly(glycidyl methacrylate) foams (MPGMA) with highly interconnected pore network were firstly prepared by high internal phase emulsions (HIPEs) template. Then carboxylated mesoporous silica nanoparticles (CMSNs) were grafted onto the interface of macroporous foams via the reaction between epoxy groups on MPGMA and carboxyl groups on CMSNs . The as-prepared HPFs composites possessed macropores ranging from 10   μm to 40   μm and uniform mesopores on average of 2.5   nm, and their large amount of carboxyl groups resulted in a favorable adsorption for λ-cyhalothrin (LC) and Cu(II). In single adsorption, the maximum adsorption capacity of HPFs for LC and Cu(II) were 80.11   mg   g −1 and 21.79   mg   g −1 at 288   K, respectively. The adsorption mechanism between LC and HPFs could be the hydrogen bonding and hydrophobic interaction, while the electrostatic attraction maybe the main interaction between Cu(II) and HPFs. Binary adsorption showed that the enhanced adsorption capacity of LC was 104.1   mg   g −1 in the presence of 15   mg   L −1 Cu(II) at 288   K, and the excellent result of Cu(II) was 22.23   mg   g −1 with the mixed solution of 50   mg   L −1 LC at 288   K, indicating the existence of promotion in adsorption ability in the case of coexistence of LC and Cu(II). Moreover, HPFs could maintain stability after five adsorption/desorption cycles in the regeneration steps.