Imagine having a simple, cost-effective, and eco-friendly solution to treat wastewater and remove heavy metals. Sounds amazing, right? Well, SDG s.r.l. has made it a reality! They have developed cutting-edge technology that leverages the chemical and physical properties of calcium carbonate and eggshells to remove heavy metals and recover valuable metals. But what are their properties?

Chemical properties of calcium carbonate

You’ve probably heard of calcium carbonate: it’s a natural, basic compound that reacts with metal ions in wastewater to form insoluble compounds. These compounds precipitate as metallic carbonates, effectively removing metals from water.

The role of eggshells

Who would have thought that eggshells could play such a role? Not only are they rich in natural calcium carbonate, but their porous structure increases the surface area available for chemical reactions. Grinding the eggshells makes them even more effective, accelerating the metal removal process.

Removal mechanisms

1. Chemical Precipitation. Metals with low solubility products, such as lead or zinc, quickly form insoluble compounds.

2. Ligand Competition. Metal ions compete for the available carbonate, with the metal having the highest affinity precipitating first.

3. pH Influence. The solution’s pH determines which metals precipitate; different metals form hydroxides or carbonates at varying pH levels.

What are the benefits of using calcium carbonate and eggshells?

Sustainability: reusing eggshells, a food by-product, reduces waste and adds value to natural materials.

Cost Efficiency: both materials are low-cost and widely available.

Versatility: they can be used in simple processes or combined with other materials, such as cement, to permanently trap metals.

Practical applications

Now for the most exciting part: where can you apply this technology in real life. Here are some options:

Heavy Metal Removal: lead, cadmium, zinc, and copper.

Valuable Metal Recovery: gold, silver, and platinum can be precipitated or adsorbed by adjusting operational conditions.

Metal Stabilization: calcium carbonate and eggshells can form stable compounds, reducing long-term environmental contamination.

Conclusions

In summary, using calcium carbonate and eggshells represents an innovative and sustainable solution for wastewater treatment. SDG s.r.l. has patented technology that is not only effective but also economical and eco-friendly. Whether for removing heavy metals or recovering valuable ones, this technology offers a wide range of industrial applications, making our world a cleaner place.

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