Instituto de Química, Campus Universitário de Ondina, Universidade Federal da Bahia, Salvador, Bahia, Brazil.
Centro de Ciências Exatas e Tecnológicas, Campus Universitário de Cruz das Almas, Universidade Federal do Recôncavo da Bahia, Cruz das Almas, Bahia, Brazil.
Biotechnol Prog. 2019 May;35(3):e2802. doi: 10.1002/btpr.2802. Epub 2019 Mar 22.
A procedure for the alkaline pretreatment of sisal fiber assisted by ultrasound was optimized to obtain a higher solubilization of hemicellulose and the removal of lignin with cellulose fraction maintenance. A full factorial design 2 was used for the evaluation of the effects of the variables (sonication time, NaOH concentration, and sonication amplitude) on the pretreatment. The optimal values for the variables using the Doehlert matrix for the sonication time, NaOH concentration, and sonication amplitude were 27 min, 4.1% (m/v), and 50%, respectively. The X-ray diffractometry and scanning electron microscopy analyses, after pretreatment, showed changes in chemical structure and morphology due to the removal of 82% of hemicellulose and 86% of lignin from sisal fiber. The soft reaction conditions and relatively short times demonstrated the effectiveness of the combined action of ultrasound with alkaline pretreatment to improve the accessibility to cellulose in this important step of the ethanol production process from biomass.
超声辅助剑麻纤维的碱性预处理工艺进行了优化，以获得更高的半纤维素溶出率和木质素去除率，同时保持纤维素部分的完整性。采用全因子设计 2 来评估变量（超声时间、NaOH 浓度和超声幅度）对预处理的影响。使用 Doehlert 矩阵确定超声时间、NaOH 浓度和超声幅度的最佳值分别为 27 min、4.1%（m/v）和 50%。预处理后的 X 射线衍射和扫描电子显微镜分析表明，由于剑麻纤维中的 82%半纤维素和 86%木质素被去除，其化学结构和形态发生了变化。温和的反应条件和相对较短的时间表明，超声与碱性预处理的联合作用在提高纤维素可及性方面是有效的，这是从生物质生产乙醇过程中的重要步骤。
