塑料催化热解制备碳纳米管生长特性和机制的研究进展

黎书江; 肖皓宇; 蒋好; 姚丁丁; 陈应泉; 王贤华; 杨海平; 陈汉平

doi:10.19906/j.cnki.JFCT.2023041

塑料催化热解制备碳纳米管生长特性和机制的研究进展

doi: 10.19906/j.cnki.JFCT.2023041

黎书江^1,,
肖皓宇^1,,
蒋好^1,,
姚丁丁^2,,
陈应泉^1,,
王贤华^1,,
杨海平^1, ,,
陈汉平^1,

1.
华中科技大学能源与动力工程学院煤燃烧与低碳利用全国重点实验室, 湖北武汉 430074
2.
华中农业大学工学院, 湖北武汉 430070

基金项目: 国家自然科学基金杰出青年基金(52125601)资助

详细信息

通讯作者:
E-mail: yhping2002@163.com

中图分类号: TK09
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出版历程
- 收稿日期: 2023-03-23
- 修回日期: 2023-05-05
- 录用日期: 2023-05-06
- 网络出版日期: 2023-05-12
- 刊出日期: 2023-08-01

Research progress in the growth mechanism of carbon nanotubes prepared by catalytic pyrolysis of waste plastics

1.
State Key Laboratory of Coal Combustion, School of Energy and Power Engineering, Huazhong University of Science and Technology, Wuhan 430074, China
2.
Engineering College of Huazhong Agricultural University, Wuhan 430070, China

Funds: The project was supported by the National Natural Science Foundation of China Outstanding Youth Program (52125601)

摘要

摘要: 催化热解技术可将废塑料转化为高品质的碳纳米管（CNTs），实现废塑料的回收和高价值利用。然而，塑料催化热解过程复杂，影响因素繁多，且碳纳米管的生长机制不清，因此，本综述从塑料种类、温度、催化剂等角度阐述了塑料结构以及热解过程对碳纳米管生长过程以及结构特性的影响，并解析了碳纳米管的成核和成长过程机理。发现挥发分种类和温度会对CNTs结构产生影响，而催化剂的性能将影响碳纳米管的直径和生长方式；催化剂与CNTs之间的作用力大小取决于催化剂的种类，CNTs边界的碳扩散强度又受反应条件、催化剂和碳源种类的影响，两者之间的相对大小决定CNTs成核和生长具体过程。该综述为废塑料热解制备碳纳米管过程的理解以及废塑料资源化利用技术的开发提供理论参考。
- 塑料 /
- 催化热解 /
- 碳纳米管 /
- 生长机理
Abstract: Catalytic pyrolysis technology can convert waste plastics into high-quality carbon nanotubes (CNTs), achieving the recycling and high-value utilization of waste plastics. However, the process of plastic catalytic pyrolysis is complex, with numerous influencing factors, and the growth mechanism of carbon nanotubes is unclear. Therefore, this article elaborates on the influence of plastic structure and pyrolysis process on the growth process and structural characteristics of carbon nanotubes from the perspectives of plastic type, temperature, catalyst, etc., and analyzes the nucleation and growth mechanism of carbon nanotubes. It is found that the type and temperature of volatile matter will affect the structure of CNTs, while the performance of the catalyst will affect the diameter and growth mode of carbon nanotubes. The force between the catalyst and CNTs depends on the type of catalyst, and the carbon diffusion intensity at the boundary of CNTs is influenced by reaction conditions, catalyst and carbon source types. The relative size between the two determines the specific process of CNTs nucleation and growth.This review provides theoretical reference for the understanding of the process of preparing carbon nanotubes from waste plastic pyrolysis and the development of waste plastic resource utilization technologies.
- plastic /
- catalytic pyrolysis /
- carbon nanotubes /
- growth mechanism

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FIG. 2573. FIG. 2573.

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图 1 不同类型废塑料催化热解的TEM照片

Figure 1 TEM images of catalytic pyrolysis of different types of waste plastics^[6] (a): PP; (b): HDPE; (c): LDPE; (d): HIPS; (e): GPPS (with permission from Elsevier)

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图 2 不同催化温度所得CNTs的SEM照片^[42]

Figure 2 SEM images for CNTs derived from different catalytic temperature^[42] (a): fresh catalyst; (b): 600 ℃; (c): 700 ℃; (d): 800 ℃; (e): 900 ℃; (f): 1000 ℃ (with permission from Elsevier)

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图 3 不同镍铁物质的量比反应催化剂的TEM照片^[59]

Figure 3 TEM analysis of reacted catalysts with different Ni to Fe mole ratio^[59] (a): NiFe1∶3; (b): NiFe1∶2; (c): NiFe1∶1; (d): NiFe2∶1; (e): NiFe3∶1; (f): Carbon yield and Raman analysis (with permission from Elsevier)

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图 4 碳纳米管成核过程（a）^[88]，碳纳米管的结构变化（b）^[82]

Figure 4 Nucleation process of carbon nanotubes (a)^[88], Structural changes of carbon nanotubes (b)^[82] (with permission from ACS Publications)

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图 5 碳纳米管生长过程^[91]

Figure 5 Growth process of carbon nanotubes^[91] (with permission from Chemistry Europe)

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表 1 不同塑料制备CNTs特性

Table 1 Summary of CNTs prepared by different plastics

Material	Catalyzer	Reactor	t/℃	CNTs/%	Diameter/nm	Ref.
PP	NiMo	single-stage fixed-bed quartz reactor	700	18.4	25.08±7.538^a 0.335^b	[10]
PP	NiMo/CaTiO₃	single-stage fixed-bed quartz reactor	700	40	24.01±4.890^a 0.340^b	[10]
PE	ferrocene	two-stage fixed-bed quartz reactor	450^c−800^d	–	(22–36)^a	[11]
PVC^e	ferrocene	two-stage fixed-bed quartz reactor	450^c−800^d	–	(22–37)^a	[11]
HDPE^f	Ni-Mn-Al	two-stage fixed-bed quartz reactor	500^c−800^d	32.6	–	[12]
HDPE/PVC	Ni-Mn-Al	two-stage fixed-bed quartz reactor	500^c−800^d	25.1	–	[12]
PP	iron nanoparticles	single-stage fixed-bed quartz reactor	700	–	16.5–40^a	[13]
PS	iron nanoparticles	single-stage fixed-bed quartz reactor	700	–	7.5–25^a	[13]
PP	Fe/ Al₂O₃	two-stage fixed-bed quartz reactor	500^c−800^d	30.2ⁱ	–	[6]
LDPE^g				35.9^h	–
HIPSⁱ				49.4^h	–
PP	NiMo/MgO^j	single-stage fixed-bed quartz reactor	700	–	(10–30)^a	[14]
PP	NiMo/MgO^k	single-stage fixed-bed quartz reactor	700	–	(10–22)^a	[14]
PP	Fe\Ni\Mg/ Mg₂Al₄Si₅O₁₈	two-stage stainless steel reactor	500^c−750^d	–	(10–30)^a 5^b	[15]
LDPE	NiMo/Al₂O₃	two-stage fixed-bed quartz reactor	(500−800)^c−(600–800)^d	14.7–28.1	(11–49)^a	[16]
HDPE	Ni/Mo/MgO	multinuclear reactor	(450–700)^c−800^d	0.76–20.1	(20–50)^a 10^l	[17]
^a:CNTs external diameter; ^b:CNTs internal diameter; ^c:Pyrolysis temperature; ^d: Catalytic temperature; ^e: Polyvinyl chloride; ^f: High density polyethylene; ^g: Low density polyethylene;^h: Containing amorphous carbon;ⁱ: High impact polystyrene; ^j: Sol gel method; ^k: Incipient wet impregnation methods; ^l: Average wall thickness

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