Layered double hydroxides/biochar composites as adsorbents for water remediation applications: recent trends and perspectives. (15th February 2021)

• Record Type: Journal Article
• Authors: dos Santos, Grazielle Emanuella de Souza; Lins, Pollyanna Vanessa dos Santos; Oliveira, Leonardo Mendonça Tenório de Magalhães; Silva, Elenara Oliveira da; Anastopoulos, Ioannis; Erto, Alessandro; Giannakoudakis, Dimitrios A.; Almeida, André Ricardo Felkl de; Duarte, José Leandro da Silva; Meili, Lucas
• Is Part Of: Journal of cleaner production. Volume 284(2021)
• Publication Date: 2021-02-15
• Subjects: Layered double hydroxides -- Biochar -- Clay-like adsorbents -- Carbonaceous material -- Contaminants removal -- Wastewater; Factory and trade waste -- Management -- Periodicals; Manufactures -- Environmental aspects -- Periodicals; Déchets industriels -- Gestion -- Périodiques; Usines -- Aspect de l'environnement -- Périodiques; 628.5
• DOI: 10.1016/j.jclepro.2020.124755
• Languages: English
• ISSNs: 0959-6526

Abstract

Abstract: Adsorption is an effective technology for wastewater treatment processes. Activated carbons are the adsorbent materials traditionally used in most of the applications but sometimes their use is limited due to the high-cost of synthesis/production and for their partial or difficult regenerability. For these reasons, scientists have turned their interest in synthesizing new and cheaper composites materials with efficient adsorptive properties. In this scenario, layered double hydroxides/biochar composites (LDHs-biochar) have attracted a great interest due to their elevated adsorption performances for a wide spectrum of pollutants, deriving from the synergistic effects arising upon the combination of LDHs with biochar. This review article focuses on the application of LDHs-biochar composites for the removal of pollutants of different nature (i.e. heavy metals, dyes, phosphate, etc.) from aqueous matrixes. Specific emphasis is given to the synthesis and characterization of these materials. Equilibrium and kinetic data are presented together with their modeling analysis and further insights about the thermodynamics of the adsorption are also provided. A specific insight into adsorption mechanisms, including the interpretation of the interactions between the solid matrix and the contaminants, was considered in this review. The review indicated that LDHs-biochar composites are promising materials that can be proficiently applied to wastewater treatment in terms of efficiency and costs demands. However, there is still a need of research efforts in order to establish this class of materials as proficient adsorbents to remove critical contaminants. Graphical abstract: Image 1 Highlights: Use of layered double hydroxides/biochar composites adsorbents for aquatic pollutant removal. Details of synthesis and characterization of layered double hydroxides/biochar composites. Maximum adsorption capacities per different pollutant classes. Presentation and summary of best isotherm e kinetic models for data interpretation.