title: Comprehensive near infrared study of Jatropha oil esterification with ethanol for biodiesel production.
abstract: This work presents a comprehensive near infrared study for in-line monitoring of the esterification reaction of high acid oils, such as Jatropha curcas oil, using ethanol. Parallel reactions involved in the process were carried out to select a spectral region that characterizes the evolution of the esterification reaction. Using absorbance intensities at 5176cm(-1), the conversion and kinetic behaviors of the esterification reaction were estimated. This method was applied to evaluate the influence of temperature and catalyst concentration on the estimates of initial reaction rate and ester conversion as responses to a 2(2) factorial experimental design. Employment of an alcohol/oil ratio of 16:1, catalyst concentration of 1.5% w/w, and temperatures at 65°C or 75°C, made it possible to reduce the initial acidity from 18% to 1.3% w/w, which is suitable for transesterification of high free fatty acid oils for biodiesel production. Using the proposed analytical method in the esterification reaction of raw materials with high free fatty acid content for biodiesel makes the monitoring process inexpensive, fast, simple, and practical.
authors.affiliation: Universidade Federal de Pernambuco, Departamento de Química Fundamental, Av. Jornalista Anibal Fernandes, s/n, Cidade Universitária, CEP, 50740-560 Recife, Brazil.
authors.forename: Alianda Dantas de
authors.initials: AD
authors.lastname: Oliveira
authors.affiliation: Universidade Federal de Pernambuco, Departamento de Engenharia Química, Av. Prof. Arthur de Sá, s/n, Cidade Universitária, 50740-521 Recife, Brazil.
authors.forename: Ananda Franco de
authors.initials: AF
authors.lastname: Sá
authors.affiliation: Universidade Federal de Pernambuco, Departamento de Engenharia Química, Av. Prof. Arthur de Sá, s/n, Cidade Universitária, 50740-521 Recife, Brazil. Electronic address: mfp@ufpe.br.
authors.forename: Maria Fernanda
authors.initials: MF
authors.lastname: Pimentel
authors.affiliation: Universidade Federal de Pernambuco, Departamento de Engenharia Química, Av. Prof. Arthur de Sá, s/n, Cidade Universitária, 50740-521 Recife, Brazil.
authors.forename: José Geraldo A
authors.initials: JG
authors.lastname: Pacheco
authors.affiliation: Universidade Federal de Pernambuco, Departamento de Química Fundamental, Av. Jornalista Anibal Fernandes, s/n, Cidade Universitária, CEP, 50740-560 Recife, Brazil.
authors.forename: Claudete Fernandes
authors.initials: CF
authors.lastname: Pereira
authors.affiliation: Universitat Rovira i Virgili, Departament de Química Analítica i Química Orgànic, Pl, Imperial Tàrraco, no. 1, E-43005 Tarragona, Spain.
authors.forename: Maria Soledad
authors.initials: MS
authors.lastname: Larrechi
mesh_terms: D000143:Acids / Q000737:chemistry; D056804:Biofuels; D001709:Biotechnology / Q000379:methods*; D002384:Catalysis; D004951:Esterification; D000431:Ethanol / Q000737:chemistry*; D031286:Jatropha / Q000737:chemistry*; D016014:Linear Models; D010938:Plant Oils / Q000737:chemistry*; D019265:Spectroscopy, Near-Infrared; D014280:Triglycerides / Q000737:chemistry
chemical_list: D000143:Acids; D056804:Biofuels; D010938:Plant Oils; D014280:Triglycerides; D000431:Ethanol
keywords: Biodiesel; Esterification; Free fatty acid; High acidity; In-line monitoring; Near infrared spectroscopy