Supercritical fluid has been expected to solubilize high-molecular biomass materials by a conversion to low molecules. In this study, we attempted to solubilize an organosolv lignin at 673K in a mixture of phenol and water, and that of benzene and water. The formation of insoluble particles, called char, which result from polymerization of organosolv lignin, was decreased to 12wt% of supplied lignin in a mixture of 1.75g phenol (0.35g/cm³) and 0.75g water (0.15g/cm³), while the char formation in a benzene-water solution was more than that in the phenol-water solutions at any mixture ratios. The soluble products from decomposed organosolv lignin in the phenol-water solution at the appropriate mixture ratio were analyzed by gel permeation chromatograph; the average molecular weight from the phenol-water solution was 388, while 1690 from a benzene-water solution. These results indicate that phenol can function as an inhibitor of polymerization of organosolv lignin, but do not benzene. Further, the chemical compounds produced from the decomposed organosolv lignin were characterized by GC-FID; GC-FID detected several low molecular compounds only from the decomposed organosolv lignin in a phenol-water solution. The inhibition mechanism of organosolv lignin polymerization by phenol at supercritical conditions was discussed.

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A new project called CAMELIA was launched in 2004 by EU to mitigate global warming by introducing multi-generation and renewable energy systems (RES) into buildings. CAMELIA stands for “Concerted Action Multi-generation Energy systems with Locally Integrated Application”. And their target is to develop a new path to reduce GHG emissions and innovative energy management through the coupling of renewable energy systems and poly-generation in eco-buildings. The first workshop was held January, 2005 and author was invited to the workshop to present the present status of cogeneration and tri-generation in Japan. A lot of discussion was made on primary energy saving and CO2 reduction by multi-generation, incentives and bottleneck of cogeneration, energy demand of eco-buildings and so on. This paper introduces the scope of CAMELIA project, the essence of the discussion, its implication to Japan and the present status of distributed energy systems (DES) in Europe.

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