Phenolic fraction recovery from pyrolysis oil obtained from paper sludge.

Abstract

The energy of biomass can be obtained by various techniques, such as combustion or by upgrading it into a more valuable fuel, gas or oil. Biomass can also be transformed into a source of value-added products for the chemical industry by using different thermochemical technologies; one of them is fast pyrolysis, which has received extensive interest in recent years. Fast pyrolysis of biomass is a thermal decomposition process that occurs in the absence of oxidizing agents. Quick biomass decomposition followed by a rapid vapor condensation converts biomass into a liquid product known as bio-oil. For the usage of bio-oil as fuel, its oxygen content must be reduced. On the other hand, if the intent is to only use it as a chemicals’ source, then the oxygen removal step may not be necessary. Many oxygen-containing chemicals now are produced from fossil fuels via oxidation or hydration of olefins to introduce oxygen-containing functional groups. In contrast, these functional groups are already present in bio-oil. The first step was to study different processes to obtain chemicals from bio-oil and to perform characterization analyses of a bio-oil from paper sludge feedstock in order to define its chemicals. Subsequently, some of the technologies to obtain these chemicals were tested to see if it was possible to obtain similar results when applying them to the bio-oil obtained from our pyrolysis process. At the end of the project an initial approach to the investigation of two methods to recover the phenolic fraction present in pyrolysis oil was done. These methods are: solvent extraction using methanol and water and phase separation injecting sulfur dioxide, and both reported promising results, being able to obtain a final product which can be used as a substitute of traditional phenol.