Comparative Analysis of CO₂ Content in Biogas and Synthetic Gas Using Chittick Titration Validated by Gas Chromatography

Abstract

This study aimed to validate the Chittick titration method for measuring carbon dioxide (CO₂) content using gas chromatography (GC) as the reference method. Two types of gas samples were analyzed: synthetic CO₂/N₂ gas with a theoretical composition of 40:60 and biogas produced by anaerobic fermentation. Analyses were conducted in parallel using both methods to compare CO₂ measurements. For synthetic gas, the Chittick titration recorded an average CO₂ content of 39.11%, whereas GC recorded 40.52%. For biogas, Chittick titration produced 30.16%, whereas GC measured 31.40%. The differences between the methods were 0.81% for synthetic gas and 1.55% for biogas, with relative errors of 2.00% and 3.45%, respectively. The t-test results showed statistically significant differences (p < 0.05) between the methods for both gas types. However, the observed deviations remained within practically acceptable limits for small-scale laboratory applications. These findings suggest that Chittick titration is a practical and cost-effective alternative for estimating CO₂ content, particularly in laboratories with limited access to gas chromatography equipment. This study is expected to serve as a useful reference for educational institutions and small laboratories that are seeking to develop simple gas analysis methods with adequate validity.