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The micronization of emodin in a mixed solution of dichloromethane and methanol by the Solution Enhanced Dispersion by Supercritical Fluids through Prefilming Atomization (SEDS-PA) process has been successfully performed. Morphologies and particle sizes (PSs) of the emodin microparticles were analyzed by scanning electron microscopy. The results of micronization show that the acicular or rod-like emodin crystals with PSs of about 3-10 µm wide and 100-300 µm long have successfully been micronized to needle-like, rod-like, twisted fiber-like and coalesced net-like microparticles with PSs of about 0.1-1.0 µm wide and 2-40 µm long by the SEDS-PA process. The effect of technological conditions on micronization has been studied. With the increase of initial solution concentration and temperature, the PSs of emodin microparticles increase. With the increase of solution flow rate and pressure, the PSs of emodin microparticles decrease.

The environmentally benign Suzuki cross-coupling reaction was developed by using ScCO2(Supercritical CO2) instead of traditionally organic solvent. In the paper the compound phenylferrocene was synthesized by the Suzuki cross-coupling reaction of iodoferrocene and phenylboronic acids in ScCO2/PEG (polyethylene glycol) with excellent yield ratio in the presence of ligand-free Pd/C catalyst and K2CO3.1.5H2O as base. The Pd/C catalyst can be reused by simply washing sequence and CO2can be recycled after depressurization. The catalytic reaction conditions were optimized in the reaction using ScCO2as solvent.