Continuous nanoparticle production by microfluidic-based emulsion, mixing and crystallization

BaSO₄ and 2,2′-dipyridylamine (DPA) nanoparticles were synthesized as reactive crystallization and anti-solvent recrystallization examples, respectively, of using the microfluidic-based emulsion and mixing approach as a new avenue of continuously producing inorganic and organic nanoparticles. BaSO₄ nanoparticles in the size range of 15-100 nm were reactively precipitated within the confinement of an aqueous droplet which was coalesced from two separate aqueous droplets containing BaCl₂ and (NH₄)₂SO₄ using a three T-junction micromixer configuration constructed with commercially available simple tubing and fitting supplies. Also, DPA nanoparticles of about 200 nm were crystallized by combining DPA+ethanol and water droplets using the same micromixer configuration.