使用超临界二氧化碳对Juglans mandshurica的木材进行脱水
Jingting Zheng1, Xi Zhu1, Lin Yang1,2
1College of Furnishings and Industrial Design, Nanjing Forestry University, Nanjing 210037, China.
Materials (Basel, Switzerland)
|August 26, 2023
概括
超临界二氧化碳 (ScCO2) 通过溶解水而有效干燥木材,而不会改变微观结构. 干燥速率主要取决于压力,不受样本长度的影响,但湿度梯度是辐射和触角形成的.
科学领域:
- 材料科学 材料科学 材料科学
- 木材科学 木材科学 木材科学
- 化学工程是化学工程的重要组成部分.
背景情况:
- 超临界二氧化碳 (ScCO2) 由于其可溶性和质量转移特性,可以提供高效的干燥.
- 在干燥过程中,ScCO2可以通过填充孔隙和溶解水来保护木材的微观结构.
- 了解ScCO2脱水对于先进的木材加工和材料保存至关重要.
研究的目的:
- 为了研究压力和温度对Juglans mandshurica*木材的ScCO2脱水效率的影响.
- 分析样本长度和方向对木材脱水率和水分含量梯度的影响.
- 评估ScCO2脱水对木材微观结构,收缩和干燥应激的影响.
主要方法:
- 两个样本的 *Juglans mandshurica* 木材 (30毫米和140毫米长度) 经过了 ScCO2 脱水.
- 实验是在四种不同的压力和温度条件下进行的.
- 湿度含量 (MC) 分布和脱水率沿纵,半径和触角方向测量.
主要成果:
- 脱水速度受到压力和温度的显著影响,压力是主导因素.
- 在相同条件下,脱水效率与样本长度无关.
- 在辐射和接触方向观察到显著的水分含量梯度,而纵向MC保持一致.
- 水的转移主要发生在纵向的端表面.
- ScCO2脱水导致木材膨胀,但没有显著的收缩或干燥应激.
结论:
- ScCO2是一种可行的,无害的木材干燥介质.
- 压力是控制ScCO2脱水率的关键参数.
- 虽然纵向的水分含量是均的,但辐射和触角梯度需要进一步研究以优化干燥.
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