Physico-Chemical Analysis of Catalysts

1. The Scientific Challenge

The project began with a challenge inherent to chemical engineering: understanding why variants of an industrial catalyst (silver particles supported on silica - Ag/SiO2) presented different catalytic activities for different batches. The key was to look beyond macroscopic behavior and understand the morphology and chemical composition of the surface, to map the cause of this difference and thus optimize catalytic activity.

2. Methodology & Analysis

We conducted a complex sweep of characterizations, building a robust portfolio of evidence:

• Electron Microscopy: Direct observation of the size and dispersion of silver particles on the surface. We observed that the diameter varied from 10 nanometers to 100 micrometers!
• Quantification: Precise determination of the mass percentage of Silver (Ag) in the samples. For some batches it was 0.5%, others 2%.
• Textural Properties: Calculation of the surface area of the silica support, which interferes with silver dispersion.
• Molecular Spectroscopy: Quantification of the present phases: metallic and oxide. According to literature, metallic silver was more active.

3. Solution in Action: Reactional Optimization

Armed with physical and chemical characteristics, we moved on to real tests in reactors. Correlating the structural data of silver in the catalyst with its empirical behavior during catalysis, we identified the activity triggers.

Result: The scientific insight allowed us to feed back the catalyst synthesis engineering. After parameterized optimization, we registered a 22% gain in the final conversion rate of the chemical route, raising practical limits and reducing process costs.