Turning Trash into Treasure: Making Useful Stuff from City Waste
China, ShanghaiTuesday, February 18, 2025
Advertisement
Advertisement
Imagine turning city trash into something useful. That's what scientists did with fly ash from big cities like Shanghai and Shenzhen. They mixed it with a special kind of sand called industrial SiO2. This mix created a special material called Al-substituted tobermorite (TOB). This TOB can be used in many ways, like cleaning up heavy metals from water.
The scientists found a way to make this TOB under milder conditions than before. They used a lower amount of a chemical called NaOH, a temperature of 160°C, and a reaction time of 24 hours. This makes the process easier and cheaper. The TOB they made had very low levels of chlorine and could trap heavy metals very well. This means it could be used to clean up polluted water.
The TOB made from Shanghai's fly ash had a higher ability to exchange cations than the one from Shenzhen. This could be because it had more chlorine. The scientists also found that the liquid left over from the process could be reused. This makes the whole process even more efficient.
Using industrial SiO2 in this way could cut the cost of the process in half. This is a big deal because it makes the process more affordable and practical. The goal of this study was to find a better way to use fly ash, which is often seen as useless waste. By turning it into something valuable, the researchers are helping to reduce waste and create useful materials.
