A recent study published in Ceramics International highlights a major advancement in environmental sustainability: the transformation of industrial slag into eco-friendly pigments. The research, conducted by teams from Threenh Technology, the University of Science and Technology Beijing, and Beijing University of Science and Technology, utilized the CR8 spectrocolorimeter to precisely measure slag color and correlate it with processing conditions.
Ore slag, a byproduct of steel, copper, and magnesium refining, has posed significant environmental challenges due to its volume and limited reuse options. Traditional recycling methods are energy-intensive and offer little value creation. This new research, however, demonstrates that by adjusting slag basicity and firing temperature, a wide range of pigments—from reddish yellow to bluish green—can be produced. The CR8 spectrocolorimeter, with its D/8 geometry and full-spectrum LED light source, provided high-precision colorimetric data (L*, a*, b*) essential for analyzing these relationships.
Key findings include that lower basicity slag yields reddish yellow pigments but causes more crucible erosion, while higher basicity produces bluish green hues. Firing temperature also affects lightness: slag fired at 1100 °C results in lighter pigments than at 1000 °C or 1200 °C. These insights enable the production of consistent, market-ready pigments from waste materials, reducing reliance on mined colorants.
The CR8 spectrocolorimeter's user-friendly vertical module allowed efficient testing of powdered slag samples, ensuring stable light path and uniform measurements. This tool not only validates the research but also paves the way for large-scale industrial application. By enabling slag-to-pigment recycling, the technology contributes to reducing landfill waste, minimizing environmental footprint, and supporting the creation of eco-friendly products such as green ceramics and coatings.
Beyond pigment production, the CR8's ability to analyze color variations can indicate changes in microstructure or erosion patterns, making it valuable for quality assurance in manufacturing. This research marks a significant step in reimagining industrial waste as a valuable resource, aligning industrial innovation with environmental protection.
