Malaysian Journal of Analytical Sciences, Vol 26 No 6 (2022): 1344 - 1377

 

MAGNETIC NANOPARTICLES AS EFFECTIVE ADSORBENTS FOR THE REMOVAL OF HEAVY METALS FROM WATER: A REVIEW OF SURFACE MODIFICATION (2015-2022)

 

(Nanozarah Bermagnet Sebagai Penjerap yang Berkesan untuk Penyingkiran Logam Berat daripada Air: Tinjauan Kajian Pengubahsuaian Permukaan (2015-2022))

 

Gimba Joshua Dagil1,2, Ng Nyuk-Ting1, Aemi Syazwani Abdul Keyon1,3*, Sheela Chandren1,3,

Wan Aini Wan Ibrahim1,3*

 

1Department of Chemistry,

Faculty of Science,

Universiti Teknologi Malaysia, 81310, Johor Bahru, Johor, Malaysia

2Department of Science, Plateau State Polytechnic, Barkin Ladi,

P.M.B 02023, Bukuru, Jos Nigeria

3Centre for Sustainable Nanomaterials,

Ibnu Sina Institute for Scientific and Industrial Research,

Universiti Teknologi Malaysia, 81310, Johor Bahru, Johor, Malaysia

 

*Corresponding author e-mail: aemi@utm.my; waini@utm.my

 

 

Received: 17 July 2022; Accepted: 27 September 2022; Published:  27 December 2022

 

 

Abstract

The use of biopolymer composite materials in the usage of magnetic nanoparticles for the removal of heavy metal pollutants has received little attention, despite their remarkable physical and chemical properties that suggested their huge potential as promising adsorbents. . Therefore, various sorbents for heavy metals removal have been prepared including surface-modified magnetic nanoparticles (MNPs). MNPs are susceptible to oxidation in the air and agglomeration in solvents rendering them to lose their essential adsorbent properties. Silica coating has proven to prevent degradation of the MNP and functionalizes the surface with silanol groups. A fundamental understanding of various surface modifications would be beneficial for near future research as well as industrial applications. Thus, this article aims in reviewing the most recent advances for surface modification of MNPs materials, including biopolymer materials, focusing on the chemistry preparation, characterization, optimization, mechanisms of adsorption, isotherms and kinetic models in order to  remove  various metals in water.

 

Keywords: magnetic nanoparticles, functionalization, modification biopolymer, heavy metals, water environment

 

Abstrak

Pengunaan komposit bioplimer sebagai nanozarah bermagnet untuk penjerapan logam berat kurang mendapat perhatian,   walaupun ianya mempunyai ciri fizikal dan kimia yang luar biasa yang menjadikan komposit bioplimer sebagai penjerap berkesan. Oleh itu, pelbagai penjerap untuk penyingkiran logam berat telah disediakan termasuk permukaan  nanopartikel bermagnet yang diubah suai (MNPs). MNPs mudah teroksida di udara dan mudah bergumpal dalam pelarut menyebabkan bahan ini kehilangan ciri-ciri penjerapan yang penting. Salutan silika telah dibuktikan menghalang kemerosotan MNPs serta menyebabkan permukaan tersebut berfungsi dengan kumpulan silanol. Pemahaman yang baik tentang pelbagai pengubahsuaian permukaan akan memberi manfaat untuk penyelidikan masa hadapan serta aplikasi industri. Maka, artikel ini bertujuan untuk membincangkan dengan lebih mendalam kemajuan terkini dalam pengubahsuaian permukaan MNP termasuk bahan biopolimer,  fokus terhadap penyediaan secara kimia, pencirian, keadaan penjerapan optimum, mekanisme penjerapan, model isoterma penjerapan dan model kinetik yang digunakan untuk penyingkiran bahan pencemar ion logam yang berbeza dalam persekitaran air.

 

Kata kunci: nanopartikel bermagnet, kefungsian, biopolimer pengubahsuaian, logam berat, persekitaran air

 

Graphical Abstract

 

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