Abstract: The present invention provides a process for removing gaseous constituents dissolved in liquid reaction mixtures in the copolymerization of alkylene oxide and carbon dioxide, characterized in that (?) prior to decompression the liquid reaction mixture has a pressure of 5.0 to 100.0 bar (absolute), wherein the following process stages are performed in the specified sequence: (i) decompression of the reaction mixture by at least 50% of the prevailing pressure, (ii) subsequent droplet separation with first defoaming and (iii) subsequent bubble separation with second defoaming to clarify the liquid phase, wherein the process stages (i) to (iii) are performed one or more times until the resulting reaction mixture has a pressure of 0.01 to <5.00 bar (absolute), and also a process for preparing polyethercarbonate polyols comprising the process stages (i)-(iii).

Abstract: Low transition temperature mixtures (LTTMs) or solvents are provided that can be used in methods and systems to dissolve and bydrolyze certain components from lignin-containing biomass (e.g., lignin) at mild conditions so that further degradation is prevented. The solvents, methods and systems according to the invention have various advantages over prior technology or approaches. For example, LTTMs are cheap solvents, renewable and/or non-toxic food ingredients. LTTMs dissolve lignin selectively from a lignin-containing biomass. A highly efficient (up to 90%) lignin recovery can be achieved. The recovered lignin is of higher quality. The remaining cellulose is also of higher. Much less water is needed, which means a tremendous reduction of the energy requirement in the recovery process, i.e. less energy needed for evaporating large quantities of water.