BS12-modified CaCO3 nanoparticle for enhancing flotation of perilla protein from its wastewater

Abstract

Perilla protein (PP) is abundant in the perilla processing wastewater, and its recovery would result in large productive and financial advantages. This work introduces a novel method, surface modified CaCO3 nanoparticle (CCNP) combined with a drainage-enhancing device, to facilitate flotation of PP. Firstly, we reported the in-situ modification of CCNP via the adsorption of mild and biodegradable surfactant, viz. dodecyl dimethyl betaine (BS12), and revealed the modification mechanisms. Interestingly, BS12-CCNP as a solid foam stabilizer increased the foam stability and improved the interfacial adsorption of PP. Secondly, we designed a waved internal component (WIC) to intensify the foam drainage and raise PP enrichment. Eventually, the recovery percentage and enrichment ratio of PP reached 91.7 ± 4.6% and 12.5 ± 0.6, respectively, with 0.7 g/L of BS12-CCNP and WIC. In conclusion, this method contributes to enhancing the separation efficiency of waste PP and provides technological insights into the nanotechnology enabled flotation.