Treatment of Wastewater from Phenolic Resin Plant with Activated Carbont

Abstract

A treatment method of the phenolic wastewater which was exhausted from the reaction tank of a phenolic resin plant was investigated. The wastewater was dark purpuric red in color, and its pH was 13.8. The analyses of the wastewater showed that it contained 44000 ppm of the chemical oxygen demand (COD), and 18000 ppm of phenols. About 61% of the COD was precipitated by the neutralization with sulfuric acid (Fig.2). About 65% of the COD in the filtrate of this neutralized wastewater was rapidly removed by the adsorption with an activated carbon. The COD adsorption capacity of the activated carbon was attained to be about 100% by weight (Fig.3∼6). The wastewater became colorless, transparent water through the carbon treatment, and the best part of the residual contaminants was proved to be methanol, which was contained in the industrial formalin of a raw material of the phenolic resin. The used carbon was regenerated by the desorption with a small quantity of alkaline solution (Fig.7∼9), and could be reused (Fig.10). About 90% of the COD in this alkaline solution which was contained much more concentrated contaminants was precipitated by the neutralization with sulfuric acid. Therefore, it was shown that the phenolic wastewater which contained a large quantity of contaminants could be clarified through the treatment with acid and activated carbon. † Adsorbents and Ion-Exchange Materials from Coal.