Sulfur crotonic acid hydrogenation

Further, Maxted (36) studied the influence of several sulfur compounds on the activity of platinum black for the hydrogenation of crotonic acid in the liquid phase. He noticed that between 15 and 50°C the toxicity remains constant for a sulfur compound, pointing out the irreversibility of sulfur adsorption. Conversely, the toxicity of various compounds increases with the molecule size. For molecules containing two sulfur atoms, losing all freedom of rotation through this double adsorption, the toxicity is less than for molecules of the same length containing only one atom of sulfur. 

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