Optimization of Cellulose Extraction and TCF Bleaching from Olive Tree Pruning Residues by Box–Behnken Design

ABSTRACT

In this work, we successfully produced Totally Chlorine Free (TCF) Bleached pulp from olive tree pruning residues using the soda-anthraquinone pulping method. TCF pulp bleaching was carried out using a chelating–hydrogen peroxide bleaching sequence. Box–Behnken design (BBD), as an experimental design for response surface methodology (RSM), was used to study the effects of the different operating conditions on the cellulose extraction and bleaching pulp and to find an optimum for each process. After pulping under optimum conditions, we obtain a yield of 28.84% for leaves and 44.18% for stems, with a kappa number of 19.74 for leaves and 36.87 for stems. Soda-anthraquinone pulps from olive tree pruning residues were then bleached with a TCF sequence, reaching a value of brightness of about 82 and a kappa number of 10.13 for leaves and 13.69 for stems. A morphological study was investigated using scanning electron microscopy (SEM), showing the raw material structures and the fiber surfaces after delignification and bleaching processes. Isolated cellulose under optimum conditions was characterized using Fourier transform infrared spectroscopy (FTIR) confirmed that cellulose amolecules were not removed using several chemical treatments both of delignification and bleaching stages.

摘要

在这项工作中, 我们使用苏打蒽醌制浆法成功地从橄榄树修剪残余物中生产出完全无氯 (TCF) 漂白浆. TCF纸浆漂白采用螯合-过氧化氢漂白顺序进行. Box–Behnken 设计 (BBD) 作为响应面法 (RSM) 的一种实验设计, 用于研究不同操作条件对纤维素提取和漂白浆的影响, 并为每个过程找到最佳方案. 在最佳条件下制浆, 叶和茎的得率分别为28.84%和44.18%, 叶和茎的卡伯值分别为19.74和36.87. 橄榄树修剪残余物的苏打蒽醌纸浆然后用TCF序列漂白, 其亮度值约为82, 叶的卡伯值为10.13, 茎的卡伯值为13.69. 利用扫描电子显微镜 (SEM) 对脱木素和漂白过程后的原料结构和纤维表面进行了形态学研究. 利用傅里叶变换红外光谱 (FTIR) 对最佳条件下分离的纤维素进行了表征, 证实了脱木素和漂白阶段的几种化学处理均未去除纤维素分子.

KEYWORDS:

• Olive tree pruning residues
• cellulose
• optimization
• Box–Behnken Design
• soda-anthraquinone pulping
• TCF bleaching

关键词:

• 橄榄树修剪残渣
• 纤维素
• 优化
• 设计
• 苏打蒽醌制浆
• 漂白.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

The project was carried out under the MOBIDOC scheme, funded by the EU through the EMORI program and managed by the ANPR.