THE INFLUENCE OF CHITOSAN CONTENT IN HYDROGEL BEADS ON THE SORPTION EFFECTIVENESS OF REACTIVE BLACK 5 DYE

Adsorbent made by carbonization of biomass under oxygen-limited conditions has become a promising material for wastewater treatment owing to its cost-effective, simple, and eco-friendly processing method. Ultrasound is considered a green technique to modify carbon materials because it uses water as the solvent. In this study, a comparison of Reactive Black 5 (RB5) adsorption capacity between biochar (BC) generated by pyrolysis of water bamboo (Zizania latifolia) husks at 600 °C and ultrasound-assisted biochar (UBC) produced by pyrolysis at 600 °C assisted by ultrasonic irradiation was performed. UBC showed a greater reaction rate and reached about 80% removal efficiency after 4 h, while it took 24 h for BC to reach that level. Scanning electron microscope (SEM) images indicated that the UBC morphology surface was more porous, with the structure of the combination of denser mesopores enhancing physiochemical properties of UBC. By Brunauer, Emmett, and Teller (BET), the specific surface areas of adsorbent materials were analyzed, and the surface areas of BC and UBC were 56.296 m2/g and 141.213 m2/g, respectively. Moreover, the pore volume of UBC was 0.039 cm3/g, which was higher than that of BC at 0.013 cm3/g. The adsorption isotherms and kinetics revealed the better fits of reactions to Langmuir isotherm and pseudo-second-order kinetic model, indicating the inclination towards monolayer adsorption and chemisorption of RB5 on water bamboo husk-based UBC.

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Preparation of nZVI embedded modified mesoporous carbon for catalytic persulfate to degradation of reactive black 5

Frontiers of Environmental Science & Engineering ◽

10.1007/s11783-020-1372-4 ◽

2021 ◽

Vol 15 (5) ◽

Author(s):

Zhifei Ma ◽

Huali Cao ◽

Fengchun Lv ◽

Yu Yang ◽

Chen Chen ◽

...

Keyword(s):

Mesoporous Carbon ◽

Reactive Black 5

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Synthesis of a New Phosphonate-Based Sorbent and Characterization of Its Interactions with Lanthanum (III) and Terbium (III)

Polymers ◽

10.3390/polym13091513 ◽

2021 ◽

Vol 13 (9) ◽

pp. 1513

Author(s):

Yuezhou Wei ◽

Khalid A. M. Salih ◽

Mohammed F. Hamza ◽

Toyohisa Fujita ◽

Enrique Rodríguez-Castellón ◽

...

Keyword(s):

High Tech ◽

Low Grade ◽

Acid Solutions ◽

Hydrogel Beads ◽

Secondary Sources ◽

Composite Sorbents ◽

Synthesis Procedure ◽

New Generation ◽

Mild Acid

High-tech applications require increasing amounts of rare earth elements (REE). Their recovery from low-grade minerals and their recycling from secondary sources (as waste materials) are of critical importance. There is increasing attention paid to the development of new sorbents for REE recovery from dilute solutions. A new generation of composite sorbents based on brown algal biomass (alginate) and polyethylenimine (PEI) was recently developed (ALPEI hydrogel beads). The phosphorylation of the beads strongly improves the affinity of the sorbents for REEs (such as La and Tb): by 4.5 to 6.9 times compared with raw beads. The synthesis procedure (epicholorhydrin-activation, phosphorylation and de-esterification) is investigated by XPS and FTIR for characterizing the grafting route but also for interpreting the binding mechanism (contribution of N-bearing from PEI, O-bearing from alginate and P-bearing groups). Metal ions can be readily eluted using an acidic calcium chloride solution, which regenerates the sorbent: the FTIR spectra are hardly changed after five successive cycles of sorption and desorption. The materials are also characterized by elemental, textural and thermogravimetric analyses. The phosphorylation of ALPEI beads by this new method opens promising perspectives for the recovery of these strategic metals from mild acid solutions (i.e., pH ~ 4).

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