e-journal

Particle morphology and mineral structure of heavy metal-contaminated kaolin soil before and after electrokinetic remediation

---

Abstract.
This study aims to characterize the physical distribution of heavy metals in kaolin soil and the chemical
and structural changes in kaolinite minerals that result from electrokinetic remediation. Three benchscale
electrokinetic experiments were conducted on kaolin that was spiked with Cr(VI) alone, Ni (II)
alone, and a combination of Cr(VI), Ni(II) and Cd(II) under a constant electric potential of 1 VDC/cm for a
total duration of 4 days. Transmission electron microscopy (TEM), energy dispersive X-ray spectroscopy
(EDX), and X-ray diffraction (XRD) analyses were performed on the soil samples before and after electrokinetic remediation. Results showed that the heavy metal contaminant distribution in the soil samples
was not observable using TEM and EDX. EDX detected nickel and chromium on some kaolinite particles
and titanium-rich, high-contrast particles, but no separate phases containing the metal contaminants
were detected. Small amounts of heavy metal contaminants that were detected by EDX in the absence of
a visible phase suggest that ions are adsorbed to kaolinite particle surfaces as a thin coating. There was
also no clear correlation between semiquantitative analysis of EDX spectra and measured total metal concentrations, which may be attributed to low heavy metal concentrations and small size of samples used.
X-ray diffraction analyses were aimed to detect any structural changes in kaolinite minerals resulting
from EK. The diffraction patterns showed a decrease in peak height with decreasing soil pH value, which
indicates possible dissolution of kaolinite minerals during electrokinetic remediation. Overall this study
showed that the changes in particle morphology were found to be insignificant, but a relationship was
found between the crystallinity of kaolin and the pH changes induced by the applied electric potential.

Keywords:
Electrokinetics
Remediation
Clays
Heavy metals

---

Ketersediaan

Tidak ada salinan data

Informasi Detail

Judul Seri

Journal of Hazardous Materials

No. Panggil

-

Penerbit

London : Elsevier B.V.., 2009

Deskripsi Fisik

Journal of Hazardous Materials 165 (2009) 548–557

Bahasa

English

ISBN/ISSN

-

Klasifikasi

-

Tipe Isi

-

Tipe Media

-

Tipe Pembawa

-

Edisi

-

Subjek

LINGKUNGAN HIDUP

Info Detail Spesifik

-

Pernyataan Tanggungjawab

agus

Versi lain/terkait

Lampiran Berkas

Komentar

---

Anda harus masuk sebelum memberikan komentar