Removal behavior and mechanism of silver from low concentration wastewater using cellulose aerogel modified by thiosemicarbazide

Abstract

Due to the low concentration of silver in water, most of the cellulose adsorbents exhibited low removal efficiency, which greatly limited their practical applications. Herein, a cellulose aerogel modified by thiosemicarbamide (CAT) was fabricated for reducing and adsorbing silver ions from low concentration wastewater. The characterization results concluded that CAT owned a threedimensional spongy structure with many circular microspheres and a better specific surface area (19.37 m 2 g À1 ), as well as the functional groups of ─C═N + ─H and ─(C═S)─N. The static batch adsorption experiments demonstrated that CAT could reached the maximum removal percentage of 94.94% and adsorption capacity of 42.12 mg g À1 under the initial concentration of Ag(I) was 15 mg L À1 and the pH value was 7. Meanwhile, the adsorption of Ag(I) on CAT was second-order reaction, and the Langmuir model could better fit the adsorption process. In addition, CAT exhibited wide pH values (1-9) adaptability and excellent adsorption performance for silver through electrostatic interaction, chelation, and reduction. This study probably provides a new method as well as important experimental data and theoretical reference for the removal of silver ions and other metals.

Adsorptive performances and valorization of green synthesized biochar–based activated carbon from banana peel and corn cob composites for the abatement of Cr(VI) from synthetic solutions: Parameters, isotherms, and remediation studies

“…These methods include processes such as adsorption [ 10 ], electrochemical reduction, ion exchange, electrocoagulation, electrodialysis [ 11 ], and membrane filtration [ 12 ]. Despite their limitations, such as reagent consumption and cost, adsorption stands out as a promising technology due to its strong surface interaction [ 13 ]. Another studies demonstrated the effectiveness of pectin-based aerogels in adsorbing Pb 2+ from wastewater, highlighting their potential in water treatment applications [ 11 ].…”

Microfibrillated cellulose reinforced poly(vinyl imidazole) cryogels for continuous removal of heavy metals

“…Various approaches involving chemical precipitation, coagulation, bioremediation, electrodeposition, and physical/chemical adsorption have been explored and developed. [13][14][15][16][17][18] Among these technologies, adsorption using a 3D porous cryogel as the adsorbent matrix for the removal of heavy metals has attracted increasing attention thanks to multiple advantages of excellent mechanical strength, operation simplicity, and low cost. 12,[19][20][21][22][23][24] The cryogel is a variety of spongy hydrogels with a supermacroporous structure produced by the ice-template, which has diverse applications in different fields including biomedical and tissue engineering, 25,26 bioseparation, 27 environmental remediation, 24,[28][29][30] and so on.…”