周围的购物:比较Cd(II) 不同的功能组的吸附性能-修饰的微晶纤维素复合材料
Wenyu Wu1, Haoyue Tang1, Shiying Bi1
1Technology Innovation Center for Land Engineering and Human Settlements, Shaanxi Land Engineering Construction Group Co., Ltd and Xi'an Jiaotong University, School of Human Settlements and Civil Engineering, Xi'an Jiaotong University, Xi'an 710049, PR China.
Carbohydrate polymers
|September 8, 2024
概括
皮中的功能化微晶纤维素 (MCC) 有效地去除 (Cd (II)). 酸修饰产生了最高的吸附能力,证明了其用于净化水的潜力.
科学领域:
- 材料科学 材料科学 材料科学
- 环境化学环境化学
- 吸附科学 吸附科学
背景情况:
- 功能化微晶纤维素 (MCC) 复合材料作为重金属去除吸附剂的结构功能关系尚不清楚.
- 皮衍生的MCC (OP-OH-H-25) 经过使用不同剂量的修饰,产生了新的吸附剂.
研究的目的:
- 调查功能化MCC吸附剂从水溶液中去除 (Cd (II)) 的有效性.
- 阐明这些新型吸附剂的结构性质关系和吸附机制.
主要方法:
- 皮衍生的MCC使用酸 (OP-OH-SH),酸 (OP-OH-P) 和甘氨酸 (OP-OH-NH2) 进行了功能化.
- 进行了批量吸附实验,以评估Cd (II) 在不同pH条件下的去除效率,动力学和容量.
- 通过对吸附特性和相互作用的分析,研究了吸附机制.
主要成果:
- 酸和酸处理增加了纤维素含量,并产生了有效的Cd(II) 吸附剂 (OP-OH-P和OP-OH-SH).
- 甘氨酸的修改导致了OP-OH-NH2具有改变的表面功能组和显著降低的Cd(II) 吸附能力.
- 通过OP-OH-P (151.81 mg/g) 和OP-OH-SH (150.80 mg/g) 实现了最大Cd(II) 吸附能力,并具有快速平衡时间 (0.25小时).
- 在复杂的水矩阵中,OP-OH-P表现出卓越的性能.
- 吸附机制涉及内部球体复合和阴离子-π 键相互作用.
结论:
- 酸是最有效的修饰剂,用于制备MCC基吸附剂去除Cd (II).
- 功能化的MCC,特别是OP-OH-P,显示出有效和快速净化Cd (II) 污染水的巨大潜力.
- 了解修饰化学对于设计高性能吸附剂至关重要.
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