Carbon tetrachloride (CTC), as a key indicator of activated carbon, plays a crucial role in the performance evaluation and waste gas treatment of activated carbon. Understanding it is of great significance for us to better choose and use activated carbon.
The carbon tetrachloride (CTC) value of activated carbon is the core indicator for evaluating its gas-phase adsorption performance. It is tested according to the national standard GB/T 7702.3-1997 and is crucial in waste gas treatment. This indicator is not simple, it directly reflects the adsorption capacity of activated carbon for volatile organic compounds (VOCs).
Specifically, it simulates the actual working conditions of treating exhaust gas by testing the dynamic adsorption performance of activated carbon on carbon tetrachloride vapor. Due to the similar diameter of carbon tetrachloride molecules and the size of common VOCs molecules, CTC values can effectively predict the performance of activated carbon in real exhaust gas environments. Moreover, its testing conditions are closer to the actual airflow state, making it a "lifeline" for evaluating gas-phase adsorption efficiency.
In the field of exhaust gas treatment, the CTC value of activated carbon has significant advantages compared to iodine value. Iodine value mainly measures the liquid-phase adsorption capacity of activated carbon for small molecule iodine, with a focus on microporous structure. However, the testing environment differs greatly from gas-phase exhaust gas, making it difficult to reflect the performance of activated carbon in actual exhaust gas treatment.
The CTC value is specifically designed for the gas phase and focuses more on the mesoporous structure, which can provide diffusion channels for VOCs molecules. Experiments have shown that the coefficient of determination between CTC value and actual VOCs adsorption efficiency exceeds 0.85, which is much higher than the iodine value of about 0.3. This fully demonstrates that CTC values can more effectively predict the performance of activated carbon in real exhaust gas environments and are more suitable for exhaust gas treatment applications.