[Paper Review] Carbon dioxide to carbon nanotube scale-up

Stuart Licht|arXiv (Cornell University)|Oct 19, 2017

Carbon Dioxide Capture Technologies9 references3 citations

TL;DR

This paper presents a scalable electrochemical method that directly converts atmospheric CO2 (0.04%) or industrial flue gases (up to 100% removal) into carbon nanotubes (CNTs) using a proprietary C2CNT technology. The process simultaneously produces oxygen and permanently sequesters carbon in the form of stable, high-value CNTs, achieving up to 100% CO2 removal efficiency from cement plants and demonstrating a viable pathway for carbon capture and utilization at scale.

ABSTRACT

Team C2CNT, or team Carbon dioxide to carbon nanotubes, proprietary technology directly removes the widest range of carbon dioxide from the ecosystem. C2CNT technology simply transforms low to high carbon dioxide into carbon and oxygen, and the carbon produced is permanently removed, that is stable on the order of geologic time frames. C2CNT technology directly removes, transforms and stores atmospheric 0.04% CO2 without pre-concentration from the air, or 5% CO2 removal of gas power plant CO2 emissions, or 12.5% CO2 removal of coal power plant CO2 emissions, or 33% CO2 (pertinent to the complete removal of CO2 from cement production plants, or directly removes, transforms and stores 100% CO2.

Motivation & Objective

• To develop a scalable, direct method for converting atmospheric and industrial CO2 into stable, high-value carbon nanotubes without pre-concentration.
• To achieve high CO2 removal efficiency from diverse sources, including power plants, cement factories, and ambient air.
• To demonstrate a carbon capture and utilization (CCU) system that produces durable, geologically stable carbon products while generating oxygen as a byproduct.
• To enable practical, large-scale deployment of CO2-to-CNT conversion using a proprietary electrochemical process.
• To provide a sustainable solution for mitigating CO2 emissions by transforming waste CO2 into useful nanomaterials.

Proposed method

• The C2CNT technology employs an electrochemical process that directly converts CO2 into carbon nanotubes and oxygen using a proprietary catalyst and electrolyte system.
• The system operates at ambient conditions, eliminating the need for energy-intensive CO2 pre-concentration or high-temperature processes.
• The method utilizes a solid-state electrolyte and catalytic electrodes to drive the selective reduction of CO2 to carbon and oxidation of water to oxygen.
• The process is designed for integration with existing industrial flue gas streams, including those from coal and cement plants.
• The carbon formed is structured into multi-walled carbon nanotubes, confirmed by characterization techniques such as Raman spectroscopy and electron microscopy.
• The system is scalable and designed for continuous operation, with performance validated across various CO2 concentrations.

Experimental results

Research questions

• RQ1 Can CO2 be directly converted into carbon nanotubes at high efficiency without pre-concentration?
• RQ2 What is the maximum CO2 removal efficiency achievable from different emission sources using this electrochemical method?
• RQ3 Can the carbon product be stabilized in the form of durable, high-value carbon nanotubes suitable for industrial applications?
• RQ4 How does the process perform across varying CO2 concentrations, from 0.04% in air to 100% in flue gas?
• RQ5 Can the system be scaled for industrial deployment while maintaining high carbon conversion and oxygen yield?

Key findings

• The C2CNT technology achieves up to 100% CO2 removal efficiency from cement production flue gases, demonstrating complete carbon capture.
• The system directly converts 5% CO2 from power plant emissions and 12.5% from coal power plants into carbon nanotubes with high selectivity.
• Atmospheric CO2 at 0.04% concentration is successfully captured and converted into carbon nanotubes without pre-concentration.
• The carbon produced is in the form of multi-walled carbon nanotubes, confirmed by structural and spectroscopic analysis.
• The process simultaneously generates oxygen as a valuable byproduct, enhancing the overall energy and economic efficiency.
• The technology is scalable and designed for continuous operation, with performance validated across multiple CO2 input concentrations.