Removal of formaldehyde from acrylic acid production wastewater

Wastewater from production of acrylic acid through catalytic oxidation of propylene exhibits a high formaldehyde content (approx. 12-14 g/L), which renders direct biological treatment of this water difficult. This paper introduces a procedure for formaldehyde removal from this wastewater employing chemical treatment consisting in adding urea to wastewater with following removal of formed solid-reaction product by filtration or centrifugation. The efficiency of formaldehyde removal through this procedure is about 99.5%, thus markedly reducing toxicity and inhibitory effect of the wastewater on activated sludge. The reaction product, which is urea-formaldehyde resin, is a technically utilizable potential material.