Abstract: The invention provides a process for continuously preparing polyether alcohols using DMC catalysts, which comprises, in a first step, in a continuous reactor, adding alkylene oxides onto H-functional starter substances and transferring the output of this reactor to a second step in a reactor which is divided by closed trays into mutually separate sections, known as compartments, which are connected to one another by external pipelines, in which the output of the reactor from the first step of the reaction passes through the compartments in succession.

Abstract: The invention provides a process for continuously preparing polyether alcohols using DMC catalysts, which comprises, in a first step, in a continuous reactor, adding alkylene oxides onto H-functional starter substances and transferring the output of this reactor to a second step in a reactor which is divided by closed trays into mutually separate sections, known as compartments, which are connected to one another by external pipelines, in which the output of the reactor from the first step of the reaction passes through the compartments in succession.

Abstract: A heterogeneous ruthenium catalyst comprising silicon dioxide as support material, in which the percentage ratio of the Q2 and Q3 structures Q2/Q3 in the silicon dioxide determined by means of solid-state 29Si-NMR is less than 25, a process for preparing a bisglycidyl ether of the formula I where R is CH3 or H, by ring hydrogenation of the corresponding aromatic bisglycidyl ether of the formula II in which the abovementioned heterogeneous ruthenium catalyst is used, and a bisglycidyl ether of the formula I which can be prepared using the abovementioned process.

Abstract: A continuous process for preparing sugar alcohols by catalytic hydrogenation of an aqueous solution of a saccharide, which forms the corresponding sugar alcohol on hydrogenation, in the presence of a ruthenium catalyst which is obtainable by: i) single or multiple treatment of an amorphous silicon-dioxide-based support material with a halogen-free aqueous solution of a low-molecular-weight ruthenium compound and subsequent drying of the treated support material at below 200° C., ii) reducing the solid obtained in i) with hydrogen at from 100 to 350° C., step ii) being carried out immediately after step i), which comprises, before the hydrogenation, bringing the aqueous saccharide solution to be hydrogenated into contact with the support material.