Eliane Lazzari
Universidade Federal do Rio Grande do Sul, Brazil
Title: Production and chromatographic characterization of bio-oil from the rice husk pyrolysis
Biography
Biography: Eliane Lazzari
Abstract
One interesting and abundant source of biomass is the rice husk, mainly in Rio Grande do Sul state (south of Brazil), where approximately 12.6 million tons per year of rice husk is produced [1]. The disposal of this waste is a serious environmental problem due to their properties (difficult to decompose), and its high phenolic content turnning highly toxic for rivers or lakes [2]. An alternative to reduce the amount of rice husk is its convertion into bio-oil by pyrolysis process [3]. Pyrolysis not only reduces its amout, as transform it in a added value chemicals (bio-oil) and a interesting solid residue (biochar) with pitential use as adsorbent or for soil enrichment. For a convincing application of the bio-oil, is need to characterize it completely, defining what are the major compounds and what are their concentration levels. Only after this, it is possible to propose a recovery route of these compounds from the original biomass. In this study, it was produced a bio-oil from the fast pyrolisis (100 ºC/min) rice husk and detailed studied its composition by GCxGC/TOFMS. Pyrolysis was conducted in a fixed bed reactor (lab-scale) using following parameters: 6.5 g of sample (0,5-1 mm), oven heating from 25 °C to 650 °C at 100 °C/min and nitrogen flow of 1 L/min [3]. The yield of the rice husk bio-oil (with aqueous phase) obtained under these conditions was 36.5 %. The use of GC×GC/TOFMS allied to software tools and Retention Index calculated for each compound according to Van den Dool & Kratz’s equation [4] were very important in the characterization of bio-oil compounds allowing the identification of 149 compounds. Our results showed that a composition of rice husk bio-oil was predominantly phenolic (32.6%) which is intersesting for replace fossil phenol for the production of chemicals. The major constituents in this oil were found to be 2-methoxy-phenol (5.09%), 1,2-benzenediol (4.05%). Another class of compounds with high concentration were the furanones (2(5H)-furanone - 3.93%), which can be used in the industry of heterocycles and pesticides. The pyrolysis of rice husk proved to be a good alternative for the diminution of the large amount of this residue.