ENVIRONMENTAL CONTAMINATION BY HEAVY METALS: REFORMULATION OF AN ALQUID TYPE ENAMEL PAINT WITH HIGH LEAD CONCENTRATIONS (Pb)

Abstract

The research is aimed at mitigating the environmental impacts caused by the use of pigments with high lead content in alkyd-type gloss enamel paints. Due to the growing social and political awareness for the conservation of the environment and the prevention of damage to health, it is necessary to evaluate the behavior of new lead-free materials. The objective of the present investigation was to reformulate a glossy alkyd enamel with high concentrations of lead, through the substitution of the yellow pigment of lead sulfochromate (inorganic type) by a lead-free pigment (organic type), maintaining the standards of quality of the product and whose lead concentration does not exceed the maximum limits allowed by international regulations. For this, a commercial formula supplied by the company was used, which was reformulated, determining the quality tests such as non-volatiles, weight per gallon, viscosity, degree of dispersion, drying tests (to the touch, free of traces, hard), adhesion, 60o angle gloss, leveling, coverage, color, flotation, weather resistance, dripping, container stability, degree of sedimentation and, finally, the effectiveness of the substitution was validated, by determining the concentration of Lead in reformulated paint. The inductively coupled plasma mass spectrometry (ICP-MS) technique was used and the digestion process of the dry product was carried out under the methodology of the NTE INEN 2123:1998 standard. The experimental results show that the current yellow paint yielded a lead content of 289,620 ppm, expressed as metallic lead, determined on a dry basis or total non-volatile content, and when reformulated, a glaze with a lead content of 110 ppm was obtained, a very satisfactory result that is below the regulations established in Latin America with a maximum of 600 ppm