Volatile organochlorine compounds (VOXs) contained in biogas can cause many technological and ecological problems. The combustion of biogas containing VOX can lead to corrosion of the system and the formation of toxic by-products (polyhalogenated dioxins and furans) and other emissions into the atmosphere. Therefore, a new method based on physical absorption was developed in this study. In order to meet the requirements of green chemistry and green engineering, new deep-eutectic solvents (DES) made from natural components were used in the absorption studies. Several physical properties of new DESs were determined, followed by an explanation of the mechanism of absorbent formation using spectroscopic analysis and density functional theory. The most important absorption parameters, ie type of DES, gas flow, type of matrix gas, temperature and initial concentrations of the VOXs have been optimized. The results obtained show that DES is composed of syringol and levulinic acid in a molar ratio of 1: 1, can efficiently absorb VOXs. In addition, the DES regeneration studies showed that the absorption capacities of DES did not change after ten absorption-desorption cycles. Studies of the absorption mechanisms indicate that the H-bond and van der Waals interactions are the main driving force behind the removal of VOX from biogas.