| Revista: | Electronic journal of biotechnology |
| Base de datos: | PERIÓDICA |
| Número de sistema: | 000398049 |
| ISSN: | 0717-3458 |
| Autores: | Bayat, Oktay1 Arslan, Volkan2 Bayat, Belgin3 |
| Instituciones: | 1Cukurova University, Mining Engineering Department, Adana. Turquía 2General Directorate of Minerals Research and Exploration, Adana. Turquía 3Cukurova University, Environmental Engineering Department, Adana. Turquía |
| Año: | 2011 |
| Volumen: | 14 |
| Número: | 3 |
| Paginación: | 1-10 |
| País: | Chile |
| Idioma: | Inglés |
| Tipo de documento: | Artículo |
| Enfoque: | Analítico, descriptivo |
| Resumen en inglés | Colemanite is one of the most important underground riches of Turkey, having approximately 60% of the world boron deposits, and it has a large portion in the deposits. In this study, chemical leaching and biological leaching methods were used for production of boric acid from colemanite (2CaO · 3B 3 O 3 · 5H 2 O) (Emet -Kütahya, Turkey). Oxalic acid concentr ation, temperature, stirring time and solid -to -liquid ratio were taken as parameters in the chemical leaching process. It was found that the dissolution rate increases with increasing oxalic acid concentration and temperature but it decreases at higher sol id-to -liquid ratios in the chemical leaching process. Using optimum conditions (d 100 = 0.075 mm; 5% solids by weight; 0.55 M oxalic acid; 80 ± 2ºC leaching temperature; 150 rpm stirring speed; 90 min leaching time) for colemanite sample (28.05% B 2 O 3 ) on ch emical leaching with oxalic acid experiments, the calculated boric acid extraction efficiency from colemanite ore was 97.89%. Optimum conditions on bioleaching of Emet -Kütahya, Turkey colemanite ores using the fungus Aspergillus niger were found to be as f ollows: reaction temperature 25 ± 2 o C; solid -to -liquid ratio 5% solids by weight; d 100 = 0.075 mm; stirring speed 150 rpm; initial the fungus populations in the inocula about 3 x 10 7 cells/ml and reaction time 21 days. The calculated boric acid extraction efficiency from colemanite ore was 90.18% under the optimum conditions. Bioleachate contained 12.95 g/l B 2 O 3 , 6.60 g/l Ca and 0.087 g/l Mg. Compared with chemical leaching at 5% pulp density, the fungus was less efficient in the extraction of B 2 O 3 from colemanite but the difference in the extraction yields between the two processes was less than 10%. Although bioleaching generally requires a longer period of operation compared to chemical leaching, these results suggest that bioleaching by A. niger |
| Disciplinas: | Biología, Química |
| Palabras clave: | Bacterias, Hongos, Fermentaciones, Aspergillus niger, Biolixiviación, Acido bórico, Lixiviación, Colemanita, Acido oxálico |
| Keyword: | Biology, Chemistry, Bacteria, Fungi, Fermentation, Aspergillus niger, Bioleaching, Boric acid, Lixiviation, Colemanite, Oxalic acid |
| Texto completo: | Texto completo (Ver PDF) |
