Outstanding Paper Awards Subcommittee of Journal of Chemical Engineering of Japan has assessed the 147 papers published in volume 43 into 2010, and the editorial board finally selected the four papers for JCEJ Outstanding Paper Awards of 2010; those are the papers on "Application of a Microreactor in the Oxidative Dehydrogenation of Propane to Propylene on Calcium Hydroxyapatite and Magnesium ortho-Vanadate Doped and Undoped with Palladium," "On-Line Property Prediction for Industrial Slurry High-Density Polyethylene Processes with Various Grade Transition Modes," " Development of Dimethyl Ether Production Process Based on Biomass Gasification by Using Mixed-Integer Nonlinear Programming," and " Direct Simulation Model of Concentrated Particulate Flow in Pressure-Driven Dead-End Microfiltration."