Elimination of Tar in Biomass Gasification Process: Liquid–Liquid Equilibrium of Ternary Systems {Water + Solvent ( p -Xylene and Methyl Hexadecanoate) + Model Molecules of Tar (Thiophene, Pyridine, Naphthalene, Phenathrene, and Anthracene)}

Nowadays attention is focused on biomass as a renewable energy source, but still one of the remaining drawbacks to be solved is the elimination of the high level of tar present in the syngas from the gasification process of the biomass. The objective of this work is to perform experimental measurements of liquid–liquid equilibria that will be used for the operation of tar removal from the gasification process. With this aim, the liquid–liquid equilibrium of water + solvent (p-xylene or methyl hexadecanoate) + model molecules of tar (thiophene, or pyridine, or naphthalene, or phenanthrene, or anthracene) were studied at 303.2, 323.2, and 343.2 K. The obtained data were correlated with the nonrandom two-liquid and universal quasi-chemical models.