聚硫酸) 接种SiO2纳米颗粒:合成和使用为煤水泥的不溶性分散剂
Guanghua Zhang1,2, Ruijun Liu2, Wanbin Zhang1,3
1Shaanxi Collaborative Innovation Center of Industrial Auxiliary Chemistry and Technology, Shaanxi University of Science and Technology, Xi'an 710021, China.
Polymers
|January 11, 2025
概括
一种新型的不溶于水的分散剂,聚 styrene 硫酸盐) 接种的SiO2纳米粒子 (SiO2-g-PSSNa),显著提高了煤水泥 (CWS) 的粘度和稳定性. 这种分散剂比传统选择提供了更高的性能,表明水不可溶性对于有效的分散剂工程来说并不必不可少.
科学领域:
- 材料科学 材料科学 材料科学
- 化学工程是化学工程的重要组成部分.
- 合体和表面化学
背景情况:
- 煤水污泥 (CWS) 技术需要有效的分散剂来优化燃料性能.
- 现有的分散剂,如聚乙硫酸盐 (PSSNa) 和硫酸盐 (LS),在性能和稳定性方面存在局限性.
- 新型高性能分散剂的开发对于推进CWS应用至关重要.
研究的目的:
- 为CWS应用合成和表征一种新的不溶于水的分散剂SiO2-g-PSSNa.
- 评估SiO2-g-PSSNa作为CWS中的分散剂的性能,重点是降低粘度和稳定性.
- 阐明SiO2-g-PSSNa.提升性能背后的机制.
主要方法:
- 通过表面化和表面启动的原子转移基聚合 (SI-ATRP) 来合成SiO2-g-PSSNa.
- 使用FTIR,XPS,EDS,NMR和TGA进行表征.
- 通过CWS准备,粘度测量,风湿学建模 (Herschel-Bulkley),形稳定性指数 (TSI) 和棒透测试来评估性能.
主要成果:
- 成功合成并验证了SiO2-g-PSSNa.的结构.
- 最佳分散剂剂量确定为0.3%.
- 与PSSNa和LS相比,SiO2-g-PSSNa显示出优异的粘度降低和更高的最大煤载量 (64.2%).
- 与PSSNa (0.30) 和LS (0.36) 相比,用SiO2-g-PSSNa制备的CWS表现出明显改善的稳定性 (TSI为0.05).
- 该机制涉及对煤表面的吸附,增加电荷密度,增强静电排斥,从而降低粘度和提高稳定性.
结论:
- SiO2-g-PSSNa是CWS的高效分散剂,性能优于商业替代品.
- SiO2-g-PSSNa的分支结构和高电荷密度是其卓越性能的关键.
- 水不可溶性不是有效分散剂设计的先决条件;充电密度是一个更关键的因素.
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