Sustainable synthesis of graphene-based adsorbent using date syrup.

ABSTRACT: Here we demonstrate, a facile in-situ strategy for the synthesis of environmentally benign and scalable graphene sand hybrid using date syrup as a sustainable carbon source through pyrolysis at 750?°C. Raman and SEM images revealed that the as-prepared date syrup-based graphene sand hybrid (D-GSH) had imperfections with macroporous 2-D graphene sheet-like structures stacked on the inorganic sand support. The applicability of the D-GSH for decontaminating the water from cationic (Methyl Violet, MV) and anionic (Congo Red, CR) dye and heavy metals (Pb²⁺ and Cd²⁺) was tested. Batch experiments demonstrated that D-GSH showcased exceptional capability for both dye and heavy metals removal with fast adsorption following pseudo-second-order kinetics. The adsorption capacities for MV, Pb²⁺, and Cd²⁺ were respectively 2564, 781 and 793?mg/g at 25?°C, the highest capacity graphene-based adsorbent reported in the literature to date. In addition, D-GSH also exhibited high adsorption capacity for anionic dye, CR (333?mg?g^-1) and good recyclability (3 cycles) for all the contaminants. The thermodynamic studies further confirmed that the adsorption of all contaminants was thermodynamically feasible, spontaneous and endothermic with ?H° of 48.38, 89.10, 16.89 and 14.73?kJ/mol for MV, CR, Pb²⁺ and Cd²⁺, respectively. Thus, utilization of a simple one-step strategy to produce graphenic sand hybrid using date syrup helped in developing a cost-effective and environmentally friendly dye and heavy metal scavenger that can be used as a one-step solution for water decontamination.

SUBMITTER: Khan S 

PROVIDER: S-EPMC6889283 | biostudies-literature | 2019 Dec

REPOSITORIES: biostudies-literature