Adsorption/Desorption Capability of Potassium-Type Zeolite Prepared from Coal Fly Ash for Removing of Hg2+

Abstract

The feasibility of using potassium-type zeolite (K-type zeolite) prepared from coal fly ash (CFA) for the removal of Hg2+ from aqueous media and the adsorption/desorption capabilities of various potassium-type zeolites were assessed in this study. Potassium-type zeolite samples were synthesized by hydrothermal treatment of CFA at different intervals (designated CFA, FA1, FA3, FA6, FA12, FA24, and FA48, based on the hours of treatment) using potassium hydroxide solution, and their physicochemical characteristics were evaluated. Additionally, the quantity of Hg2+ adsorbed was in the order CFA, FA1 < FA3 < FA6 < FA12 < FA24 < FA48, in the current experimental design. Therefore, the hydrothermal treatment time is important to enhance the adsorption capability of K-type zeolite. Moreover, the effects of pH, temperature, contact time, and coexistence on the adsorption of Hg2+ were elucidated. In addition, Hg2+ adsorption mechanism using FA48 was demonstrated. Our results indicated that Hg2+ was exchanged with K+ in the interlayer of FA48 (correlation coefficient = 0.946). Finally, adsorbed Hg2+ onto FA48 could be desorbed using a sodium hydroxide solution (desorption percentage was approximately 70%). Our results revealed that FA48 could be a potential adsorbent for the removal of Hg2+ from aqueous media.

Selective adsorption of Hg(ii) with diatomite-based mesoporous materials functionalized by pyrrole–thiophene copolymers: condition optimization, application and mechanism

“…[5][6][7] Among these methods, adsorption technology is widely acknowledged as one of the most promising methods for mercury removal in terms of its low cost, easy operation and design simplicity. With the rapid development of adsorbents, conventional adsorption materials, such as metal organic framework, carbon nanotube, layered double hydroxides, zeolite and clays, [8][9][10][11][12] have been widely applied to remove heavy metals. Mesoporous materials are used as new adsorbents to remove organic pollutants and heavy metals in water owing to their large BET surface area, pore size, pore volume, regular pore structure and good hydrothermal stability.…”

Column study using modified banana pseudo stem as adsorbent for removal of Pb (II)

“…Hence, research focus should be aimed at continuous processes and at scaling up and meeting the requirements for secondary or tertiary sludge treatment. A wide range of adsorbents have been used to remove heavy metal ions, including Pb(II), such as silica gel [ 11 ], activated alumina [ 12 ], activated carbon [ 13 , 14 ], fly ash [ 15 ], sugarcane bagasse [ 16 ], natural clay [ 17 ], zeolites [ 18 ], nanomaterial's [ 19 , 20 ], polymer based [ 21 ] adsorbents fish scales [ [22] , [23] , [24] , [25] , [26] ] and mollusk shells [ 27 , 28 ].…”

Coal Fly Ash‐based P Zeolite‐anchored CuxO as an Efficient Catalyst for Heterogeneous Photo‐Fenton Degradation of Methylene Blue

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