加氢改性调控褐煤结构促进煤基碳纳米管的形成：碳纳米管碳源的探索,ACS Omega

当前位置： X-MOL 学术 › ACS Omega › 论文详情

Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)

加氢改性调控褐煤结构促进煤基碳纳米管的形成：碳纳米管碳源的探索
ACS Omega ( IF 3.7 ) Pub Date : 2023-07-12 , DOI: 10.1021/acsomega.3c01736
Qingxiang Guo _{1,

2} , Yuqiong Zhao _{1,

2,

3} , Yaning Lei _{1,

2} , Guoqiang Li _{1,

2} , Yajun He _{1,

2} , Guojie Zhang _{1,

2} , Yongfa Zhang _{1,

2} , Kunjie Li ₃

Affiliation

尽管许多研究已经实现了煤基碳纳米管（CNT）的制备，但煤的碳源结构与CNT生长之间的关系尚未深入研究。在这项研究中，我们以褐煤和KOH为原料和催化剂，通过水热改性调整褐煤结构，以促进催化热解过程中碳纳米管的形成。从煤的结构变化和热解特性探讨了碳纳米管的主要碳源。结果表明，褐煤热解产物的CNT收率仅为2.39%，但在亚临界水-CO体系中对褐煤进行水热改性后，CNT收率显着提高。随着改性温度的升高，石墨化度、有序度和CNT含量不断增加，其中CM ₃₄₀的CNT含量最高，为9.41%。加氢改性促进芳香碳结构的重排，生成通过短脂肪链和芳香醚键连接的更稠合的芳香环。这些结构的变化与碳纳米管的形成密切相关，并导致煤热解过程中释放的碳源成分的变化。与褐煤相比，改性煤在催化热解过程中释放出更多的芳香族化合物，尤其是≥3环的多环芳烃和酚类物质，有利于转化为碳簇，为CNT生长提供碳源。另外，改性煤释放的含碳气体（CH ₄和CO）比褐煤略多，这对CNT的生长影响有限。这项研究提供了一种通过煤的分子剪裁策略来增强碳纳米管生长的新颖有效的方法。

"点击查看英文标题和摘要"

Tuning Lignite Structure via Hydromodification To Promote the Formation of Coal-Based CNTs: Exploration for the Carbon Source of CNTs

Although the preparation of coal-based carbon nanotubes (CNTs) has been realized in many studies, the relationship between carbon source structure of coal and CNT growth has not been studied in depth. In this study, we used lignite and KOH as raw material and catalyst and tuned lignite structure via hydrothermal modification to promote the formation of CNTs during catalytic pyrolysis. The main carbon source of CNTs was explored from the change of coal structure and pyrolysis characteristics. The results indicate that the CNT yield of lignite pyrolysis products is only 2.39%, but the CNT yield increases significantly after lignite was hydrothermally modified in a subcritical water–CO system. The graphitization degree, the order degree, and CNT content increase continuously with the increase in modification temperature, and C-M₃₄₀ has the highest CNT content of 9.41%. Hydromodification promotes the rearrangement of aromatic carbon structures to generate more condensed aromatic rings linked by short aliphatic chains and aromatic ether bonds. The variation of these structures correlates well with the formation of CNTs and leads to the change in the carbon source components released during coal pyrolysis. Compared to lignite, modified coal releases more aromatic compounds, especially polycyclic aromatic hydrocarbons with ≥3 rings and phenols during catalytic pyrolysis, which is conducive to the transformation into carbon clusters and provides carbon sources for CNT growth. In addition, modified coal releases a slightly more carbon-containing gas (CH₄ and CO) than lignite, which has a limited effect on the growth of CNTs. This study provides a novel and efficient method for enhancing the growth of CNTs by a molecular tailoring strategy of coal.

更新日期：2023-07-12

点击分享查看原文

点击收藏

公开下载

阅读更多本刊新发论文本刊介绍/投稿指南