Highly crosslinked 3-D hydrogels based on graphene oxide for enhanced remediation of multi contaminant wastewater

[Display omitted] •Hydrogel based on natural material by simple process was prepared.•In an easy way, graphene oxide cross-linked with functionalized guargum was synthesized.•The bio-hydrogels were characterized by FTIR, SEM, XRD, BET and Rheological studies.•The plausible mechanism in remove Cu(II), MG, RhB and MB from aqueous solution are illustrated.•The regenerated hydrogel can be reused upto 3 cycles. Hydrogels are three dimensional materials with modifying surface which containing more functional groups and it is used in many applications such as hygienic products, agriculture, drug delivery systems, sealing, coal dewatering, food additives and pharmaceuticals. Mostly, it is implemented in biomedical applications like tissue engineering and regenerative medicines, diagnostics, wound dressing, separation of biomolecules or cells and barrier materials to regulate biological adhesions and in biosensors. Herein we report the preparation of aminated guar gum/graphene oxide (AGG/GO) hydrogel using borax as a crosslinker, which has a high surface area with a crosslinked structure for enhanced removal of dyes and heavy metals. The chemical moieties, morphological and structural properties of the AGG/GO hydrogel were examined by Fourier Transform Infrared Spectrometer (FTIR), Scanning Electron Microscope (SEM), X-ray diffraction (XRD) and Brunauer–Emmett–Teller (BET) analysis respectively. The swelling properties of hydrogels were demonstrated, followed by viscoelastic studies using rheological analysis found that the material is stable up to an applied frequency of 10 Hz. Interestingly, removal efficiency of the AGG/GO hydrogels for Cu(II), Malachite green, Methylene blue and Rhodamine B dyes were found to be 88, 98, 90, and 75% respectively from aqueous solutions.