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Liquid-phase hydrogenation of crotonaldehyde in non-polar and polar solvents was studied on monometallic Pd, Pt, Ir, Re catalysts using mesoporous Sibunit and Al2O3 as supports. In the presence of Pd the -C=C- bond of crotonaldehyde was preferably hydrogenated to form butanal, while butanal and crotyl alcohol are formed over Ir catalysts. Crotonaldehyde hydrogenation in 1,4-dioxane did not exhibit further butanal to butanol hydrogenation. Application of Re as a catalyst leads to formation of crotyl alcohol, with activity being, however, twofold lower than of Ir catalysts. Pt/C is almost inactive in the hydrogenation of crotonaldehyde. Formation of crotyl alcohol occurs most efficiently over Ir/Al2O3 in aprotic nonpolar solvents (decane), with selectivity to crotyl alcohol increasing with temperature showing 30% at 25% conversion under 180 °C and hydrogen pressure 0.84 MPa. Crotonaldehyde hydrogenation in a polar protonic solvent (ethanol) results in butanal ac

Reliable estimation of kinetic parameters in chemical systems comprising both slow and rapid reaction steps and rapidly reacting intermediate species is a difficult differential-algebraic problem. Consequently, any conventional approach easily leads to serious convergence and stability problems during the parameter estimation. A robust method is proposed to surmount this dilemma: the system of ordinary differential equations and nonlinear algebraic equations is converted to ordinary differential equations, which are solved in-situ during the parameter estimation. The approach was illustrated with two generic examples and an example from green chemistry: synthesis of dimethyl carbonate from carbon dioxide and methanol.