Identification of Hydrocarbons Characteristics Using Low-Power Laser Absorption Spectroscopy

This study presents an experimental investigation into the detection of hydrocarbons using low-power laser absorption spectroscopy at 532 nm. Oil–water emulsions (0–4% v/v) were stabilized with a surfactant and analyzed in transmission. A hydrocarbon fingerprint was derived from the absorption band at 520–525 nm. The system demonstrated high sensitivity (<0.5%), rapid response, and strong linear correlation with concentration (R² = 0.992). The method achieved a limit of detection (LOD) of 0.29% and a limit of quantification (LOQ) of 0.97%. These results highlight the suitability of compact diode-laser systems for low-cost environmental monitoring and industrial safety.