Acrylic acid reactor design

The separation of products is usually acconq>lished by first absorbing reactor-2 effluent into water, followed by extraction of the organics into a solvent such as butyl acetate, and distillation to recover the solvent, acrylic acid and acetic acid, and aqueous and organic wastes. However, if relatively high propylene and low steam concentrations in the feed are used, extraction can be dispensed with. In file interest of minimization of processing, this design will be enqiloyed, but it does require recycle. 

There are several possible causes for the off-specification acrylic acid product. The most likely causes are changes that may have occurred during shutdown. Perhaps the new catalyst is not performing as designed. Perhaps the new solvent is contaminating the product. The reactor effluent and the extractor effluent streams should be checked for contamination. Suppose that has been done, and everything has been found to be within normal conditions. Therefore, the most likely cause involves the tenperature in the acrylic acid distillation column. In this column, acrylic acid and acetic acid are separated. It will be assumed that this is a simple binary distillation. 

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