Upgrading Liquid Products: Notes from the Workshop at the International Conference Research in Thermochemical Biomass Conversion

A workshop was held at the International Energy Agency conference, Research in Thermochemical Biomass Conversion, on the subject of upgrading liquid products. The workshop discussion focused on the two prominent methods of liquids upgrading, catalytic hydroprocessing and catalytic cracking. Catalytic hydroprocessing as applied to biomass liquids relies heavily on petroleum developed technology; similar catalysts and operating conditions are used although lower space velocities are typical. The need for stabilization of the pyrolytic products prior to hydroprocessing was also discussed. Catalytic cracking of biomass liquids also relies heavily on petroleum processing technology. Zeolitic catalyst development has focused on the ZSM-5 of Mobil and its application to pyrolysis products. Significant olefinic gas yields are obtained in the zeolitic processing of biomass pyrolyzates and the conversion of these to liquid fuels is a primary research goal. Aromatic gasoline is the primary product in both catalytic processes. A general conclusion of the workshop participants was that the cost of liquid fuels for internal combustion engines would be higher in the foreseeable future. Due to the high cost of initial biomass liquefaction plants (including upgrading) a more likely near-term product would be aromatic chemicals produced under constrained economic circumstances.