Evaluation of the synergistic effect in adsorption and ultrafiltration for the treatment of pharmaceutical sludge-washed leachate.

Cellulosic sludge discharged from the pharmaceutical production industry possesses heterogeneous and complex physicochemical and biological properties. The disposal of non-recyclable pharmaceutical sludge, particularly concerning leachate, continues to negatively impact storage and landfill sites. Treating leachate is often viewed as a poor investment. However, managing leachate at industrial storage areas and landfill sites is essential to ensure environmental safety. A straightforward batch adsorption system was investigated to implement a low-cost system in this context. This system utilized naturally activated carbons derived from coconut husks and papaya seeds as adsorbents, followed by ultrafiltration (UF) processed at room temperature. The primary treatment provided by the adsorption system significantly enhances the UF process by improving its speed. Most pollutant components are removed to the point of being untraceable. The average efficiency of the primary adsorption process was 58% for both Coconut Husk Activated Carbon (CHAC) and Papaya Seeds Activated Carbon (PSAC). However, the effectiveness of adsorption varied for different components, with removal rates ranging from 15% to 100% (untraceable). Without adsorption, direct UF treatment achieved a potential efficiency of 79% but faced severe fouling issues, making it unsuitable for regular commercial use. The efficiency of the processes was evaluated through biochemical oxygen demand (BOD), chemical oxygen demand (COD), and 17 other removal parameters. The synergistic effect of combining adsorption followed by UF presents a viable solution, both technically and economically, for future applications.