Direct fabrication of hierarchically processed pineapple peel hydrogels for efficient Congo red adsorption

Herein, the hierarchically processed pineapple peel was achieved by water (WT-PP), alkali (AT-PP), bleaching (BT-PP) and bleaching-alkali (PPC) treatments respectively for separate or simultaneous removal of hemicellulose and lignin. These treated pineapple peel were further fabricated into hydrogels (WT-PPH, AT-PPH, BT-PPH and PPCH, respectively) by a facile dissolution-regeneration process in ionic liquid. The structure and Congo red (CR)...