Research

Publications
Title: Natural adsorption of methylene blue by waste fallen leaves of Magnoliaceae and its repeated thermal regeneration for reuse
First author: Guo, Dabin; Li, Yuexin; Cui, Baihui; Hu, Mian; Luo, Shiyi; Ji, Bin; Liu, Yu
Journal: JOURNAL OF CLEANER PRODUCTION
Years: 2020
Volume / issue: 267 /
DOI: 10.1016/j.jclepro.2020.121903
Abstract: In this study, waste fallen leaves of Magnolia denudate (MDL), Magnolia grandiflora (MGL) and Michelia figo (MFL) were used as adsorbent for removing soluble methylene blue (MB) from aqueous solution. Results showed that the maximum adsorption capacity of MDL, MGL, and MFL were determined to be 185.19 mg/g, 149.25 mg/g, and 238.10 mg/g, which was higher than other reported leaf-based materials. It was found that the adsorption of MB by fallen leaves was a spontaneous and endothermic process, which could be described by Langmuir isotherm (R-2 > 0.995) and pseudo-second-order kinetics (R-2 > 0.992). Moreover, an environmentally friendly thermal method was applied for regeneration of used adsorbents, by which used MFL was converted to stable MFL-biochar with satisfactory adsorption capacity (139.40 mg/g) for three consecutive cycles. Electrostatic attraction between MB and carboxyl groups was identified as the main mechanism of the observed adsorption. Overall the article provided a novel material as well as regeneration method for potential environmental-sustainable dye wastewater treatment.