(115g) Biomasspyrolyisrefinery: Pyrolysis Oil Hydrodeoxygenation

Pyrolysis Oil Hydrodeoxygenation

H. Pucher, R. Feiner, N. Schwaiger, P. Pucher*, M. Siebenhofer

Graz University of Technology, Institute of Chemical Engineering and Environmental Technology, *BDI-BioEnergy International AG

Non-renewable energy sources such as oil and coal will not suffice the increasing demand of energy in the future. It is assumed that renewable resources such as Biomass are able to fill this dawning gap because they have been considered as the most promising energy sources in the next century [1]. In addition the European Commission has released a directive to increase the volume of renewable biofuels within the field of automotive fuels to 10% by 2020 [2].

To fill the upcoming gap and meet the requirements of the directive a biomass liquefaction concept from renewable resources is presented in this work. The BiomassPyrolysisRefinery concept consists of two main process steps. In the first step lignocellulosic biomass, like wood and straw, is converted in pyrolysis oil and pyrolysis char through liquid phase pyrolysis. In the second step these two products are upgraded. Two promising upgrading technologies are investigated in this concept: hydrodeoxygenation [3] [4] of pyrolysis oil and hydrogenation of pyrolysis char. Through hydrodeoxygenation the polar, highly acidic, water and oxygen rich pyrolysis oil is converted in an appropriate, carbon rich, oxygen and water poor product phase. Then the upgraded product is ready for further processing in a conventional refining process.

The main focus of this project is to investigate and optimize the upgrading of pyrolysis oil to maximize the output of the carbon rich fraction and raise stability. For that purpose, the pyrolysis oil is dehydrated prior to the hydrodeoxygenation step. The water content can be reduced by 90%, (Table 1). Then the operation parameters for hydrodeoxygenation, like hydrogen pressure, temperature, reaction time and catalysts, are determined. Investigations have been carried out in lab size and batch mode.

Table 1: Comparison of Pyrolysis Oil, Pyrolysis Oil dehydrated and Crude Oil [5].

A Conversion of pyrolysis oil to carbon rich product phase of about 45% has already been obtained. This results indicate that it is possible to control and supress the unwanted reactions like repolymerisation. The composition and characterisation of the products were determined by GC-MS, elemental analysis, NDIR continuous gas analysis and by a solvent-solvent extraction procedure defined by Oasmaa [6].