Adsorption and catalysis

Summary

• 1. The hydrogenation of maleic and fumaric acids was investigated in a circulating system, using a potentiometric method.

• 2. As well as the parts of the catalyst surface capable of adsorbing both acids, there were other parts which could adsorb only maleic or fumaric acids from a given mixture.

• 3. The extent of the hydrogenation reaction for a given component depended on the fraction of the surface which it occupied.

• 4. In the hydrogenation of mixtures, it was necessary to make use of the actual reaction velocities, particularly in cases when there was no preferential adsorption of one component.

• 5. Addition of thiophene to a mixture of the acids reduced to zero their hydrogenation and the adsorption of maleic acid, reduced the adsorption of fumaric acid, and only slightly reduced the catalyst potential beyond the decrease produced by the mixed acids.

• 6. There was a qualitative parallel between adsorption and fall in potential.

• 7. The experimental results on adsorption and kinetic interaction, obtained in our work, were in agreement with the hydrogenation theory of Balandin.