Upgrading of coconut fibers Bio-Oil: An investigation By GcxGc/Tofms

Pyrolysis of agroindustrial waste is an important way to add value to this material avoiding its discard in the environment. However, when residues are derived from oilseeds or similar, it is possible to find a large amount of fatty acid derivatives in the biomass and later in bio-oil composition. These compounds are not adequately thermo-degraded in pyrolysis processes, reducing the quality. Another common compound class and with a high added value present in bio-oils are phenols. In this work two forms of upgrading processes were performed in coconut fiber pyrolysis process. One of them is the alkaline extraction of coconut fiber bio-oil in order to produce a high acidic and a neutral fraction. The other upgrading process is a biomass pretreatment before the pyrolysis, using two different extraction techniques (Soxhlet and ultrasound). The two processes proved to be efficient and complimentary: in the first case, there was the pre-concentration of the phenols in a single fraction and in the second one, a great part of the fatty acids derivatives were removed from the bi-oil. These results indicate that the two techniques can be used to improve the quality of bio-oil produced by removing the free fatty acids from biomass and isolating compounds with high added value (in the case of phenols).