It is known that gas generated through plastic pyrolysis is abundant in hydrocarbons and can serve as a raw material for carbon nanotubes (CNTs). However, there has been no research evaluating both the economic and environmental feasibility of an upcycling process using pyrolysis gas to produce CNTs. A comparative evaluation was conducted between the upcycling process and the conventional process using methane as a carbon source, and each process was performed at laboratory scale. We report that the cost of the upcycling process (2,999 $ kg) is comparable to that of the conventional process (2,930 $ kg), and that this slight cost disadvantage can be mitigated by reducing the Ar flow rate by 20%. Upcycling process involving pyrolysis has a greater impact on climate change than conventional process. However, this disadvantage can be significantly mitigated up to 19.38 kgCOeq by substituting the power generation method with renewable energy source. Enhancing the prerequisites and technological maturity of upcycling processes can contribute to the expansion of the pyrolysis industry and the realization of a circular economy, thereby promoting green growth.

中文翻译：

---

实验室规模的塑料升级回收与绿色增长：从经济和环境方面评估塑料废物升级回收为碳纳米管


据了解，塑料热解产生的气体富含碳氢化合物，可以作为碳纳米管（CNT）的原材料。然而，目前还没有研究评估使用热解气生产碳纳米管的升级回收过程的经济和环境可行性。对升级回收工艺和使用甲烷作为碳源的传统工艺进行了比较评估，并且每个工艺都在实验室规模下进行。我们报告说，升级回收工艺的成本（2,999 $ kg）与传统工艺的成本（2,930 $ kg）相当，并且可以通过将 Ar 流量降低 20% 来缓解这种轻微的成本劣势。涉及热解的升级回收过程对气候变化的影响比传统过程更大。然而，通过用可再生能源替代发电方法，可以显着缓解这一缺点，最高可达 19.38 kgCOeq。提高升级回收工艺的先决条件和技术成熟度有助于扩大热解产业和实现循环经济，从而促进绿色增长。