[Establishment and Improvement of Portable X-Ray Fluorescence Spectrometer Detection Model Based on Wavelet...

Area of Science:

• Environmental Science
• Analytical Chemistry
• Spectroscopy

Context:

• Heavy metal contamination in soil poses significant environmental and health risks.
• Accurate and rapid detection methods are crucial for effective soil remediation and management.
• Portable X-ray fluorescence (pXRF) spectrometry offers on-site analysis capabilities.

Purpose:

• To develop and validate a robust method for on-site heavy metal (Cr, Cu, Zn, As, Pb) quantification in soil using pXRF.
• To optimize the wavelet transform technique for denoising and smoothing pXRF spectra, enhancing signal quality.
• To assess the stability, accuracy, and precision of the pXRF instrument after applying the optimized wavelet-based detection model.

Summary:

• Soil samples were analyzed using pXRF, with spectra denoised via wavelet threshold filtering (coif3 basis, level 3 decomposition).
• Standard curves were established, showing high linearity (R2 = 0.990-0.996) for heavy metal concentrations (0-1,500 mg·kg⁻¹).
• The optimized method demonstrated detection limits below national soil standards, with good instrument stability and precision.

Impact:

• The validated wavelet-enhanced pXRF method provides a reliable tool for rapid, on-site screening of heavy metals in contaminated soils.
• This approach significantly improves the accuracy and precision of pXRF analysis, facilitating timely environmental assessments.
• The study contributes to advancing field-based analytical techniques for environmental pollution monitoring and control.