Agglomeration of lead particles

Addition of I2 and Iodides such as C2H5I, CI4, Pbl2, etc. helps prevent the agglomeration of lead particles. This reduces the volume of the by-product, elemental lead, and results in readily stirred reaction masses, thereby Increasing the capacity of the autoclaves [229]. Bromine and CsHgEr have been found to be slightly less effective [229]. 

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