Comparative leaching behavior and immobilization of heavy metals in ceramic matrices derived from refinery oily sludge using TCLP and EN 12457-2.
- 1Department of Environmental Sciences, University of Thessaly, Gaiopolis, Greece.
Abstract
The increasing generation of refinery oily sludge (ROS) poses significant environmental challenges due to its high content of hazardous heavy metals, requiring effective stabilization methods. This study investigated the leaching behavior and immobilization efficiency of 31 elements in ceramic matrices incorporating ROS, comparing the toxicity characteristic leaching procedure and European standard (EN) 12457-2 protocols to evaluate environmental risk. Ceramic specimens were prepared with 0, 5, and 10 wt.% ROS and sintered at 950°C and 1050°C. Leachates were analyzed via inductively coupled plasma mass spectrometry to quantify elemental mobility. Results demonstrated high immobilization efficiency; Cu remained consistently below detection limits (<0.001 mg/kg) in all samples, while Zn concentrations remained stable across both firing temperatures and protocols. Firing temperature significantly influenced Cr mobility; in the EN 12457-2 protocol, increasing the temperature to 1050°C reduced Cr leaching from 0.529 mg/kg to undetectable levels for 5% wt. ROS content. However, specific variations were observed at higher waste loadings, with Cr reaching 4.590 mg/kg in the 10% wt. ROS samples at 1050°C, suggesting complex phase transformations. Ni was consistently immobilized below detection limits, and Pb showed minimal mobility in isolated cases. These findings confirm that ceramic processing is a viable stabilization technique for ROS, generally reducing metal mobility below regulatory limits. The study concludes that while higher sintering temperatures enhance the matrix stability for most elements through vitrification, the interaction between waste loading and temperature is non-linear, requiring precise optimization for large-scale applications.
Related
- Mechanisms and Effectiveness of Biochar, Zeolite and Attapulgite for Heavy Metal Immobilization in Soils: A Comparative Review
- Aged commercial imidacloprid formulation alters the thermal, optical, and electrical behavior of aqueous matrices
- Transcontinental transport of a massive SO 2 plume from the Tehran refinery explosion in March 2026 observed from space
- Synergistic Electrocoagulation–Electro-Fenton Coupling for Petroleum Refinery Wastewater Mineralization: Statistical Optimization and Cost Analysis
- Structure and leaching characteristics of basaltic glass-ceramics for immobilizing simulated actinides La, Ce and Nd
BibTeX
@article{kaffe2026comparative,
title = {{Comparative leaching behavior and immobilization of heavy metals in ceramic matrices derived from refinery oily sludge using TCLP and EN 12457-2.}},
author = {Dimitra Kaffe and Xenophon Spiliotis},
journal = {Journal of environmental quality},
year = {2026},
month = nov,
doi = {10.1002/jeq2.70323},
url = {https://europepmc.org/article/MED/42998137},
note = {CC BY-NC-ND},
}
RIS
TY - JOUR
TI - Comparative leaching behavior and immobilization of heavy metals in ceramic matrices derived from refinery oily sludge using TCLP and EN 12457-2.
AU - Dimitra Kaffe
AU - Xenophon Spiliotis
PY - 2026
DA - 2026/11/01
JO - Journal of environmental quality
DO - 10.1002/jeq2.70323
UR - https://europepmc.org/article/MED/42998137
AB - The increasing generation of refinery oily sludge (ROS) poses significant environmental challenges due to its high content of hazardous heavy metals, requiring effective stabilization methods. This study investigated the leaching behavior and immobilization efficiency of 31 elements in ceramic matrices incorporating ROS, comparing the toxicity characteristic leaching procedure and European standard (EN) 12457-2 protocols to evaluate environmental risk. Ceramic specimens were prepared with 0, 5, and 10 wt.% ROS and sintered at 950°C and 1050°C. Leachates were analyzed via inductively coupled plasma mass spectrometry to quantify elemental mobility. Results demonstrated high immobilization efficiency; Cu remained consistently below detection limits (<0.001 mg/kg) in all samples, while Zn concentrations remained stable across both firing temperatures and protocols. Firing temperature significantly influenced Cr mobility; in the EN 12457-2 protocol, increasing the temperature to 1050°C reduced Cr leaching from 0.529 mg/kg to undetectable levels for 5% wt. ROS content. However, specific variations were observed at higher waste loadings, with Cr reaching 4.590 mg/kg in the 10% wt. ROS samples at 1050°C, suggesting complex phase transformations. Ni was consistently immobilized below detection limits, and Pb showed minimal mobility in isolated cases. These findings confirm that ceramic processing is a viable stabilization technique for ROS, generally reducing metal mobility below regulatory limits. The study concludes that while higher sintering temperatures enhance the matrix stability for most elements through vitrification, the interaction between waste loading and temperature is non-linear, requiring precise optimization for large-scale applications.
SN - 0047-2425
SN - 1537-2537
ER -