Hazardous by-products can form due to several reasons:
Incomplete Reactions: Not all reactants may convert to the desired product, leading to the formation of unwanted compounds. Side Reactions: Additional reactions may occur that produce harmful substances. Catalyst Degradation: Over time, catalysts can degrade and produce hazardous substances. Impurities in Feedstock: Contaminants in the starting materials can lead to the formation of unwanted by-products.