Functionalized Bentonite Clay Composite with NiAl-Layered Double Hydroxide for the Effective Removal of Cd(II) from Contaminated Water

Muhammad Shafiq, Abdulrahman Ali Alazba and Muhammad Tahir Amin ()
Additional contact information
Muhammad Shafiq: Alamoudi Water Research Chair, King Saud University, Riyadh 11451, Saudi Arabia
Abdulrahman Ali Alazba: Alamoudi Water Research Chair, King Saud University, Riyadh 11451, Saudi Arabia
Muhammad Tahir Amin: Alamoudi Water Research Chair, King Saud University, Riyadh 11451, Saudi Arabia

Sustainability, 2022, vol. 14, issue 22, 1-16

Abstract: In this study, the efficiency of functionalized bentonite (F-bentonite) and NiAl-layered double hydroxide (LDH), as well as their nanocomposites, was explored regarding the adsorption of cadmium ions (Cd 2+ ) in batch tests. Surface characterization using SEM, EDX, and FTIR analyses confirmed the successful loading of LDH (NiAl) onto the F-bentonite and the adsorption of Cd 2+ onto the F-bentonite, LDH (NiAl), and LDH/F-bentonite composite adsorbent, suggesting ion exchange and surface precipitation as the main controlling mechanisms of the formation of adsorbent. An equilibrium contact period of 60 min was suggested, with the LDH/F-bentonite composite presenting the highest adsorption capacity and removal effectiveness as compared to the other adsorbents. The LDH/F-bentonite composite also presented the highest removal efficiency and maximum adsorption capacity at an optimum pH value of 7.0. A steady increase in the uptake capacity of Cd 2+ was observed by increasing the dosage of the adsorbents, with the LDH/F-bentonite composite having the best adsorption capacity. The fitting of the pseudo second-order kinetic model to the adsorption data of Cd 2+ suggested chemisorption on the adsorbents’ surfaces as the controlling mechanism. The Langmuir isotherm with a near-perfect fitting revealed a monolayer adsorption, while physical adsorption of Cd 2+ onto all the adsorbents is proposed using the D–R isotherm. Finally, both homogeneous and heterogeneous adsorption systems are proposed for all the adsorbents due to the satisfactory fitting of the Sips and R–P isotherm models.

Keywords: adsorption mechanism; composite adsorbents; kinetic and isotherm; optimum capacity; physical adsorption (search for similar items in EconPapers)
JEL-codes: O13 Q Q0 Q2 Q3 Q5 Q56 (search for similar items in EconPapers)
Date: 2022
References: View complete reference list from CitEc
Citations:

Downloads: (external link)
https://www.mdpi.com/2071-1050/14/22/15462/pdf (application/pdf)
https://www.mdpi.com/2071-1050/14/22/15462/ (text/html)

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:gam:jsusta:v:14:y:2022:i:22:p:15462-:d:979527

Access Statistics for this article

Sustainability is currently edited by Ms. Alexandra Wu

More articles in Sustainability from MDPI
Bibliographic data for series maintained by MDPI Indexing Manager ().