Enhancing antibiotic recovery from its wastewater using thiol-functionalized SNPs as a collector and a novel foam separation column

Effective recovery of antibiotic from their wastewater is an important but challenging work. Here, a promising process of foam separation had been validated for the recovery of streptomycin sulfate (SS) from its wastewater and the SS concentration in wastewater was 110.0 ± 2.8 mg/L. Firstly, thiol functionalized silica nanoparticles (t-SNPs) were prepared to enhance their adsorption capacity, and they acted as the collectors to capture SS. Moreover, a novel foam separation column containing a polyethylene tube was developed to strengthen foam drainage. A low liquid holdup of the foam was achieved because the polyethylene tube contributed to accelerating the flow of entrained liquid in the exterior channels. Under the suitable conditions of pH 7.0, t-SNPs concentration 500 mg/L and volumetric air flow rate 700 mL/min, the recovery percentage and enrichment ratio of SS reached 90.1 ± 4.5% and 82.4 ± 4.1, respectively. Furthermore, desorption experiments were performed for isolating SS from the t-SNPs and the desorption percentage of SS reached 91.3 ± 4.6% after four cycles. Overall, this work had a significant meaning for the treatment of antibiotic-contaminated wastewater.