Brazilian Mineral Clays: Classification, Acid Activation and Application as Catalysts for Methyl Esterification Reactions
نویسندگان
چکیده
In this study, three raw Brazilian clays from Joao Pessoa, Paraiba State (Aco AP, AVL and Verde Lodo) were characterized before after purification acid activation. Several instrumental techniques used, the classified as dioctahedral smectites with different compositions, where sample had highest content of montmorillonite. addition, analyses showed modification in clay mineral mainly due to removal impurities octahedral sheet cation leaching during activation, which resulted specific areas ranging 42 93 m2 g-1 increase Bronsted/Lewis site ratio, until 1.52 (AVL). Then, methyl esterification reactions performed using acid-activated catalysts. The maximum conversions obtained 92 64%, for acetic activated lauric Lodo, respectively, these data correlated Bronsted-Lowry acidity.
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ژورنال
عنوان ژورنال: Journal of the Brazilian Chemical Society
سال: 2021
ISSN: ['0103-5053', '1678-4790']
DOI: https://doi.org/10.21577/0103-5053.20200164