The influence of technological parameters like hydrogen pressure, temperature, glycerol concentration in aqueous solution, amount of catalyst, stirring speed, and reaction time on glycerol hydrogenolysis to 1,2‐propanediol over a Cu/Al2O3 catalyst prepared by coprecipitation was investigated. Functions describing the process were glycerol conversion as well as selectivity to 1,2‐propanediol and to by‐products in the liquid and gas phase. The structure and properties of synthesized Cu/Al2O3 were characterized by X‐ray diffraction, energy dispersive X‐ray microanalysis, BET surface area, average pore volume, and pore diameter. Catalyst recycle studies were also performed.

The influence of technological parameters on dehydrochlorination of dichloropropanols to epichlorohydrin performed on a reaction-stripping column and a prereactor was studied. For a fixed flows of dichloropropanols solution, lime milk solution, and steam through the column, the conversion of dichloropropanols and the yield of epichlorohydrin were calculated. The influence of an excess of lime milk solution, recirculation of the water layer of the distillate from the column, the rate of steam flow through the column, and an excess of calcium hydroxide over dichloropropanols on the course of the process was studied. Moreover, the effects of the reaction time and temperature of the prereactor were tested.

Based on statistical experimental design methodology, the single-response optimization of technological parameters of glycerol hydrogenolysis to 1,2-propanediol was performed. The independent factors (technological parameters) considered were the following: hydrogenolysis temperature, glycerol concentration in water, concentration of catalyst, and reaction time. The technological parameters were selected based on our previous, preliminary studies carried out by the single variable function method. The single-response optimization was performed using the rotatable uniform design. The optimized functions were glycerol conversion and selectivity of transformation to 1,2-propanediol.

The iron compounds (iron(III) oxide-hydroxide monohydrate FeO(OH) × H 2 O, iron(III) oxide Fe 2 O 3 , and ascorbic acid) were used as oxygen scavengers modifiers in laminating of polymer films. This oxygen-scavenging system was coated on preselected films (low density polyethylene [LDPE] and polyethylene terephthalate [PET]) from which the laminates were formed. It presents the new form of composite material packaging that has the function of oxygen scavenging, which could be suitable for food packaging. The scope of the research included studies of morphology of oxygen scavengers by scanning electron microscope and their average particle size distribution measure by particle size analyzer, the effect of type, and concentration of these substances on viscosity of adhesive and seal strength of laminates.The Fourier-transform infrared spectroscopy (FTIR) of laminates was also performed to observe the potential interaction of functional groups of polyurethane adhesives with oxygen scavenger components. The most important ability of the developed system for oxygen scavenging was confirmed by measuring oxygen concentration (% vol) in a headspace with the prepared laminates. The concentrations of selected oxygen scavengers (4-6 wt%) and their combinations were studied. The most effective oxygen scavenger system integrated within the PE/PET composite film consists of 6 wt% ascorbic acid and 1 wt% FeO(OH) × H 2 O, where the oxygen concentration of 1.0 vol% (±0.20 vol%) was obtained after 15 days of storage. It was found that in this system the oxygen scavenging reaction occurs through ascorbate oxidation to dehydroascorbic acid, which is catalyzed by reduction of Fe 3+ to Fe2 + ions.

High activity of copper based catalysts for C-O bond hydro-dehydrogenation and their poor activity for C-C bond cleavage1 have prompted an attempt to apply such catalysts in the hydrogenolysis of glycerol to 1,2-and 1,3-propanediol. In the present study the infl uence of hydrogen reduction time of the Cu/ Al 2 O 3 and CuCr 2 O 4 copper catalysts on glycerol conversion and selectivity of transformation to propanediols and by-products was studied. At fi rst a general comparison was made between the commercial catalysts and those prepared by the co-precipitation method. As better results were obtained in the presence of catalysts prepared by co-precipitation, they were selected for further detailed studies of the infl uence of reduction time. For both prepared catalysts Cu/Al 2 O 3 and CuCr 2 O 4 the reduction time of 8 h was optimal. In the presence of Cu/Al 2 O 3 catalyst the conversion of glycerol was 59.0%, selectivity of transformation to 1,2-propanediol 77.4% and selectivity to 1,3-propanediol 1.9%. In the presence of CuCr 2 O 4 the glycerol conversion was 30.3% and selectivity to 1,2-propanediol 67.3%.

Glycerol hydrogenolysis was studied in the presence of CuCr2O4 catalyst both commercially available and prepared by co-precipitation. The two catalysts were characterised by transmission electron microscope (TEM), X-ray diffraction (XRD), Raman spectroscopy and X-ray microanalyses. CuCr2O4 prepared by co-precipitation method was used to study the influence of technological parameters on glycerol hydrogenolysis to 1,2- and 1,3- propanediol. The effect of temperature, hydrogen pressure, glycerol concentration, amount of catalyst and stirring speed was investigated.

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