A carregar...
Publicação
Production of biodiesel from waste cooking oils and its purification using adsorption techniques with natural adsorbents
| Nome: | Descrição: | Tamanho: | Formato: | |
|---|---|---|---|---|
| 361.92 KB | Adobe PDF |
Orientador(es)
Resumo(s)
The world's energy demands are steadily increasing each year, promoting the exploration of cleaner and more sustainable alternatives to classical fossil sources. In this context, biodiesel emerges as a promising candidate for replacing fossil diesel, making a significant contribution to carbon emissions reduction. One notable advantage lies in the ability to utilize waste cooking oils (WCO) as a feedstock for biodiesel production. This practice not only mitigates waste but also transforms a previously
underutilized resource into a valuable source of renewable energy, thereby promoting sustainability and energy efficiency. Currently, 95% of biodiesel production relies on first-hand feedstock due to its high conversion into fatty acid ethyl esters (FAEEs) or fatty acid methyl esters (FAMEs) . However, this study introduces the utilization of Waste Cooking Oil (WCO) as a greener approach to biodiesel production. Biodiesel production can be achieved through alkaline catalyzed transesterification, with the aim of meeting the standards specified by EN 14214 at the end of its production process. Therefore, crude biodiesel obtained from the transesterification step needs to undergo glycerol purification in order to comply with the norm specification of a maximum free glycerin content of 0.02% (w/w). Hence, the present study seeks to produce and characterize activated carbons derived from walnut shells, and evaluate its use in the removal of glycerol from crude ethanolic biodiesel produced from WCO, a possible alternative to the traditional wet washing process, which results in the loss of between 0.2L to 10L of water per liter of biodiesel produced .
In this work, titration in triplicate was employed to determine the acid value of the oil, quantified as mg KOH/g of the sample, yielding a result of 0.8355±0.0274. This provided a preliminary assessment for the determination of the necessary alkaline catalyst percentage which would mitigate parallel saponification during the transesterification process. The reaction tests, executed in duplicate, included varying catalyst proportions of 0.5%, 0.6%, and 0.7% (w/w) relative to the processed oil. Gas chromatography (GC) was employed for the characterization of the produced biodiesel, revealing that a 0.5% (w/w) catalyst load was the optimal choice, providing a consistent average yield of 89.52% in FAEEs. Biodiesel production is currently conducted via the ethanol route with 1:7.5 oil/ethanol molar ratio, considering an excess in relation to the stoichiometric molar ratio 1:3. The research is also
focused on the production of activated carbon materials, involving both chemical and physical activation techniques. Chemical activations will encompass the utilization of bases (KOH), acids (H3PO4), constituting a pivotal phase in enhancing the overall efficiency and sustainability of the biodiesel production process.
Descrição
Palavras-chave
Biodiesel Waste cooking oils
Contexto Educativo
Citação
Fabian, João Vitor; Guimarães, Miriam D.; Smolich, Camilla Groxko; Pokriwiecki, Ticiane S.; Queiroz, Ana; Ribeiro, António E.; Brito, Paulo (2023). Production of biodiesel from waste cooking oils and its purification using adsorption techniques with natural adsorbents. In XXVII Encontro Luso Galego de Química. Porto. ISBN 978-989-8124-40-1
Editora
Sociedade Portuguesa de Química