纳米晶体齐奥利特BEA用于区域选择性和连续性乙烯基功能化使用乙酸二氧化的anisole:催化剂停用研究
Gaddam Naresh1, Barla Madhu Krushna1, Kathkar Kondaiah1
1Department of Energy and Environmental Engineering, CSIR-Indian Institute of Chemical Technology (IICT), Tarnaka, Hyderabad 500007, India.
ACS omega
|November 29, 2023
概括
超声波预处理和水热合成产生纳米晶体化β (ZB) 催化剂. 由于性能优化,ZB-2表现出持续的异离子转化,比ZB-1和ZB-3更好地抵抗失活.
科学领域:
- 材料科学 材料科学 材料科学
- 催化剂是一种催化剂.
- 纳米技术 纳米技术
背景情况:
- 乙酸 (ZB) 催化剂对于各种化学反应至关重要.
- 在工业应用中,随着时间流 (TOS) 的推移,催化剂的停用是一个重大挑战.
- 了解合成参数和催化剂性能之间的关系对于开发稳定的催化剂至关重要.
研究的目的:
- 为了研究超声波预处理和SiO2/Al2O3比对化石β纳米晶体属性的影响.
- 为了评估合成的ZB催化剂的催化活性和失活行为,用于异离子转化.
- 为了将物理和纹理特性与催化剂性能和停用机制相关联.
主要方法:
- 用超声波预处理的热合成贝塔热 (ZB).
- 描述ZB催化剂的特征,包括晶体大小,特定表面积和中孔体积.
- 催化活性测试用于与变化时间在流 (TOS) 的anisole转换.
- 使用CHNS和TGA分析已耗尽的催化剂,以确定失活的原因.
主要成果:
- 合成了具有不同晶体大小 (9.1-22.6 nm) 的纳米晶体乙酸 (ZB) .
- 与ZB-1和ZB-3相比,ZB-2表现出优越的催化稳定性,在较长的TOS中保持高的异离子转化率 (>45%) 和较长的TOS.
- 由于焦炭形成,ZB-1和ZB-3的失活速度更快,这与更大的中孔体积和强大的产品保留有关.
结论:
- 超声波预处理和SiO2/Al2O3比率显著影响ZB催化剂的特性和催化性能.
- ZB-2的增强稳定性归因于其较小的粒子大小,较低的中孔体积和更容易获得的微孔酸度.
- 优化热酸合成参数是缓解失活和改善催化剂寿命的关键.
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