Advanced analytical methods to support biofuels technology development

Abstract

Advanced biofuels technology development is hindered by challenges that require ever-increasing understanding of the physical and chemical properties of feedstocks, intermediates, and finished fuels. Judicious application of molecular-level analytical techniques—such as high-resolution mass spectrometry, nuclear magnetic resonance spectroscopy, gas and liquid chromatography, and spectroscopic imaging—provide the resolution and sensitivity needed to comprehensively characterize advanced biofuels process streams.

At RTI International we have been developing an advanced biofuels technology that integrates a catalytic biomass pyrolysis step and a hydroprocessing step to produce infrastructure compatible biofuels and bioproducts. During the primary direct liquefaction step, catalysts are applied, and process conditions are optimized to maximize the yield and adjust the chemical composition (quality) of the liquid biocrude intermediate.
Biocrude yield is typically inversely proportional to the bulk oxygen content of the liquid intermediate but the type of oxygenates is proving important to understanding reactor fouling and hydrotreating catalyst performance during upgrading.

This is prompting new strategies for upgrading biocrude that look beyond bulk oxygen content and require advanced analytical techniques. Downstream processing options and fuel quality assessment also rely heavily on robust analytical methodologies. Moving forward, there needs to be a balance between what can be measured and what should be measured with an emphasis on applying appropriate techniques to interrogate specific process streams to guide integrated process development. Fortunately, comprehensive molecular-level details of the complex advanced biofuels process streams are starting to provide the needed insights to overcome key technical barriers for developing economically viable, scalable, and environmentally sustainable advanced biofuel technologies.