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. Th e disposal of this waste is a serious environmental problem due to their properties, diffi cult to decompose, and its high phenolic content turnning highly toxic for rivers or lakes. An alternative to reduce the amount of rice husk is its conversion into bio-oil by pyrolysis process. Pyrolysis not only reduces its amout, but transforms it in a added value chemical (bio-oil) and an interesting solid residue (biochar) with potential use as adsorbent or for soil enrichment. For a convincing application of the bio-oil, it is needed to characterize it completely, defi ning what are the major compounds and what are their concentration levels. Only aft er this, it is possible to propose a recovery route of these compounds from the original biomass. In this study, a bio-oil from the fast pyrolisis (100 ºC/min) rice husk was produced and details of its composition was studied by GCxGC/TOFMS (Time-of-fl ight mass spectrometry). Pyrolysis was conducted in a fi xed 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 the rate of 100°C/min and nitrogen fl ow of 1 L/min. Th e yield of the rice husk bio-oil, with aqueous phase, obtained under these conditions was 36.5%. Th e GC×GC/TOFMS was allied to soft ware tools and Retention Index was calculated for each compound according to Van den Dool & Kratz’s equation, were very important in the characterization of bio-oil compounds allowing the identifi cation of 149 compounds. Our results showed that a composition of rice husk bio-oil was predominantly phenolic (32.6%) which is of intersest to replace fossil phenol for the production of chemicals. Th e major constituents in this oil were found to be 2-methoxy-phenol (5.09%) and 1,2-benzenediol (4.05%). Another class of compound with high concentration was furanones (2(5H)-furanone) (3.93%), which can be used in the industry of heterocycles and pesticides. Th e pyrolysis of rice husk proved to be a good alternative for the diminution of the large amount of this residue.