title: Microwave-assisted carboxymethylation of cellulose extracted from brewer's spent grain.
abstract: Cellulose was extracted from brewer's spent grain (BSG) by alkaline and bleaching treatments. The extracted cellulose was used in the preparation of carboxymethyl cellulose (CMC) by reaction with monochloroacetic acid in alkaline medium with the use of a microwave reactor. A full-factorial 2(3) central composite design was applied in order to evaluate how parameters of carboxymethylation process such as reaction time, amount of monochloroacetic acid and reaction temperature affect the average degree of substitution (DS) of the cellulose derivative. An optimization strategy based on response surface methodology has been used for this process. The optimized conditions to yield CMC with the highest DS of 1.46 follow: 5g of monochloroacetic acid per gram of cellulose, reaction time of 7.5min and temperature of 70°C. This work demonstrated the feasibility of a fast and efficient microwave-assisted method to synthesize carboxymethyl cellulose from cellulose isolated of brewer's spent grain.
authors.affiliation: Unidade de Ciências Exatas e Tecnológicas, Universidade Estadual de Goiás, Br 153, Fazenda Barreiro do Meio, 3105, 75132-903 Anápolis, Goiás, Brazil. Electronic address: danilomartins_1@hotmail.com.
authors.forename: Danilo Martins
authors.initials: DM
authors.lastname: dos Santos
authors.affiliation: Unidade de Ciências Exatas e Tecnológicas, Universidade Estadual de Goiás, Br 153, Fazenda Barreiro do Meio, 3105, 75132-903 Anápolis, Goiás, Brazil. Electronic address: andrea_bukzem@hotmail.com.
authors.forename: Andrea de Lacerda
authors.initials: Ade L
authors.lastname: Bukzem
authors.affiliation: Unidade de Ciências Exatas e Tecnológicas, Universidade Estadual de Goiás, Br 153, Fazenda Barreiro do Meio, 3105, 75132-903 Anápolis, Goiás, Brazil. Electronic address: ascheridpr@gmail.com.
authors.forename: Diego Palmiro Ramirez
authors.initials: DP
authors.lastname: Ascheri
authors.affiliation: Unidade de Ciências Exatas e Tecnológicas, Universidade Estadual de Goiás, Br 153, Fazenda Barreiro do Meio, 3105, 75132-903 Anápolis, Goiás, Brazil. Electronic address: roberta.signini@ueg.br.
authors.forename: Roberta
authors.initials: R
authors.lastname: Signini
authors.affiliation: Unidade de Ciências Exatas e Tecnológicas, Universidade Estadual de Goiás, Br 153, Fazenda Barreiro do Meio, 3105, 75132-903 Anápolis, Goiás, Brazil. Electronic address: gilbaqui@hotmail.com.
authors.forename: Gilberto Lucio Benedito
authors.initials: GL
authors.lastname: de Aquino
mesh_terms: D000434:Alcoholic Beverages / Q000032:analysis*; D000704:Analysis of Variance; D002266:Carboxymethylcellulose Sodium / Q000737:chemistry*; D007220:Industrial Waste / Q000032:analysis*; D008855:Microscopy, Electron, Scanning; D008872:Microwaves; D008962:Models, Theoretical; D066244:Proton Magnetic Resonance Spectroscopy; D017550:Spectroscopy, Fourier Transform Infrared; D013223:Statistics as Topic; D013818:Thermogravimetry; D013997:Time Factors; D014961:X-Ray Diffraction
chemical_list: D007220:Industrial Waste; D002266:Carboxymethylcellulose Sodium
keywords: Agro-industrial residue; Brewer's spent grain; Carboxymethylation of cellulose; Microwave