Case Study: Organic Solvent and Heavy Metals Determination in Paints
Problem: A paint manufacturer requested the quantification of organic solvents and heavy metals present in their products, before releasing them on the market.
Solution: GC-FID analysis for organic solvents and ICP-OES analysis for heavy metals.
Techniques: Gas-chromatography flame ionization detection (GC-FID) and inductively coupled plasma-optical emission spectroscopy (ICP-OES).
A paint manufacturer contacted Impact Analytical to quantify organic solvents (benzene, toluene, and xylenes) and heavy metals (lead, cadmium, chromium, and mercury) in their products before releasing them on the market.
GC-FID analysis was used to measure the organic solvents present in the paint products. The solvents were extracted from the paint by mechanical shaking in the presence of an appropriate extraction medium, and analyzed against standards of benzene, toluene and xylene.
Prior to ICP-OES analysis, the paint samples were completely dissolved into an acidic aqueous solution, with the aid of a dedicated microwave digester system. The use of a microwave, rather than a hot plate, allowed to obtain higher temperatures and pressures, thus increasing the efficiency and speed of the “digestion” while minimizing sample contamination. Lead, cadmium, chromium, and mercury were then quantified using a four-points calibration curve.
SOLUTION & RESULTS
Traces of toluene and xylene were detected in only one of the paint samples, while traces of the heavy metals were found in all the analyzed samples. Both the organic solvents and heavy metals were well below the maximum allowed limits, and therefore the paint products could be safely released on the market.
Use GC-FID and ICP analyses to identify organic solvents and elements present in your products