This work deals with the use of intensified processes based on the combined use of acoustic cavitation and biosurfactants for enhancing the latex yield and colloid characteristics in the acoustic atomized microemulsion polymerization of methyl methacrylate (MMA). It was compared with an oil/water (o/w) modified atomized microemulsion process in a conventional mechanically agitated reactor. The synthesized nanoparticles were further applied for selective removal of Pb²⁺, Cd²⁺, Cu²⁺ and Fe²⁺ ions from water. Batch adsorption equilibrium was reached in 30 min and maximum uptakes for Pb²⁺, Cd²⁺, Cu²⁺ and Fe²⁺ in non-competitive adsorption mode were 86, 52, 80, and 71 mg g⁻¹, respectively at 30 °C. Adsorption data were fitted well to the Langmuir isotherm and pseudo-second-order models for kinetic study. The heavy metals loaded on these nanoparticles could be desorbed in acid or EDTA solution and the adsorption capacity of the regenerated adsorbent did not significantly decline after five cycles of adsorption–desorption cycles. Negative values of Gibb's free energy change (ΔG^o) showed that the adsorption was feasible and spontaneous and negative values of enthalpy change (ΔH^o) confirmed exothermic adsorption. A cell viability study indicated that the nanoparticle is non-cytotoxic in nature. Lastly, a continuous filtering-type water purification device was designed and constructed to successfully attain the World Health Organization standard for drinking water.