Abstract: A process is described for continuous production of anhydrosugar alcohol by continuous introducing of sugar alcohols and/or monoanhydrosugar alcohols into a reaction vessel and dehydration in the presence of an acid catalyst and solvent in which the resultant reaction product is soluble. Water and the solvent having the dissolved reaction product are each cointinuously removed from the reaction vessel. The reaction product is separated from the removed solvent and the product is optionally purified to a purity of 99.0% the solvent is recycled in the reaction vessel.

Abstract: This invention relates to a method for the selective preparation of a styrene of formula (1) ##STR1## by reacting an acetophenone of formula (1) ##STR2## with hydrogen in the presence of a catalyst containing one of several oxides, in particular metal oxides, wherein the oxide contains an element form the groups Ia, IIa, IIIa, IVa, VIa, Ib, IIb, IVb, Vb, VIb, and/or VIII or an element from the lanthanide group. The catalyst contains preferably on or several oxides of the formula ZnM.sup.1.sub.b M.sup.2.sub.c O.sub.x, where M.sup.1 stands for at least one element from the Al, Zr, Ti and Si group, M.sup.2 stands for at least one element from the Cd, Cu, Ag, Ni, Co, Fe, Mn, Cr, Mo, Ta, Sc, W, V, Nb, Hf, Yt, B, In, Zn, Pb, Bi Se, Ga, Ge, Sb, As, Te group, or an element from the lanthanides, b=0-20, c=0-3, x corresponds to the number of oxygen atoms required for stoechiometric compensation, which results in accordance with the oxidation states of Zn, M.sup.1 and M.sup.2 or oxides of formula M.sup.3.sub.2 M.sup.