Development of tandem-modulated induction thermal plasmas and their application to high rate production of nanomaterials

Abstract

We hereby present a novel approach for synthesizing functional nanopowders using tandem pulse-modulated induction thermal plasmas (Tandem-PMITP) combined with time-controlled feedstock feeding (TCFF). Tandem-PMITP utilizes two RF coils within a single plasma torch to generate an axially extended plasma. The upper coil sustains stable plasma, while the modulated lower coil generates dynamic thermal fields. This method enables efficient feedstock evaporation and robust nanoparticle nucleation, achieving high production rates of 800–1000 g/h at 20 kW for various oxides. A numerical thermofluid model has been developed to capture plasma fields, feedstock behavior, and aerosol dynamics. This model reveals that modulation-induced entrainment enhances vapor cooling and nucleation. This innovative Tandem-PMITP+TCFF system demonstrates significant potential for scalable and efficient nanoparticle production.