Color removal of industrially produced organic liquid polymer additives using ozone and various adsorbents

In plasticizer production, color is the most fundamental technical criterion determining the product's quality and the sectors in which it will be used. Since the highest acceptable color value for plasticizers under international standards is 30 Hazen (APHA), this necessitates a solution to this problem on an industrial scale. This study comprehensively examines the undesirable discoloration problem encountered in plasticizers produced using critical raw materials such as 2-Ethylhexanol (2-EH) and Pure Terephthalic Acid (PTA). To address this issue, triggered by quality variations in the raw material supply chain, storage conditions, and thermal changes during production, the combined use of oxidation and adsorption methods was investigated. Within the scope of the study, ozone (O₃) gas, a strong oxidizing agent, was used to break the chemical bonds of color-forming compounds and disrupt their structures. Concurrently, activated carbon known for its high surface area and adsorption properties was incorporated into the system to remove these broken-down waste products and other residues from the environment. During the experimental process, the effect of varying amounts of activated carbon under a fixed ozonation duration, as well as the color removal efficiency of hybrid processes combining these two methods, was analyzed. The data obtained demonstrate that while ozonation or activated carbon alone yields limited color removal, systems combining these two methods exhibit significantly higher purification performance. Consequently, this study presents a feasible, efficient, and optimized method for achieving the targeted quality standards in industrial plasticizer production.