Direct liquefaction of hydrolytic eucalyptus lignin in the presence of sulphided iron catalysts

Abstract

The liquefaction of hydrolytic eucalyptus lignin has been studied in hydrogen donor and non-donor solvents in the presence of ferrocene and of ferrocene associated with sulphur or carbon disulphide. With the exception of tetralin, all reactions were carried out at supercritical conditions of the solvent. It was found that the yields of heavy oils increase significantly with the increase in hydrogen pressure in the non-donor solvents. The oil yields also increase with the density of the solvent but level out at densities higher than 0.30 g/ml. The consumption of molecular hydrogen is significant in the non-donor solvents; in the donor solvents the hydrogen is mostly transferred from the solvent itself. In the non-donor solvents, the oil yields depend strongly on the efficiency of the catalyst, but not in the donor solvents.