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Open access

Zrinka Mastelic Samardzic and Stanka Zrncevic

1

Catalytic hydrogenation of 2-((1-benzyl-1,2,3,6-tetrahydropyridin-4-yl)methylene)-5,6-dimethoxy-2,3-dihydroinden- 1-one hydrochloride () to 2-((1-benzylpiperidin-4-yl)methyl)-5,6-dimethoxy-2,3-dihydroinden- 1-one hydrochloride (2) was investigated in the batch-slurry reactor. The 5% Pt/C catalyst was chosen to search the optimal reaction conditions because of its higher catalytic activity compared to other catalysts used in the work. To investigate the catalyst activity, selectivity and stability, the effect of agitation speed, catalyst loading, solvent, temperature, hydrogen pressure and catalyst reuse were studied.

The initial rate of hydrogenation increases with the increase of catalyst loading, with the temperature and solvent polarity, if alcohols were used as solvents. The hydrogenation rate decreases with higher hydrogen pressure and that was explained by competitive adsorption of both reactants.

The results also indicate that 5% Pt/C is a promising catalyst for 1 hydrogenation because at relatively mild reaction conditions selectivity towards main product was high (98%) and catalyst maintains its activity during successive runs.

Open access

Karolina Valkaj, Ozren Wittine, Karmen Margeta, Teresa Granato, Andrea Katović and Stanka Zrnčević

Phenol oxidation with hydrogen peroxide using Cu/ZSM5 and Cu/Y5 catalysts

In this work, catalytic activity and stability of Cu/Y5 and Cu/ZSM5 zeolites in phenol oxidation with hydrogen peroxide were examined. The catalyst samples were prepared by the ion exchange method of the protonic form of commercial zeolites. The catalysts were characterized by the powder X-ray diffraction (XRD), AAS, while the adsorption techniques were used to measure the specific surface area.

The thermal programmed desorption of NH3 (NH3-TPD) was used for measuring the total number of acid sites formed on the surface of zeolites.

Catalytic performance of the prepared samples was monitored in terms of phenol, hydrogen peroxide and total organic carbon (TOC) conversion, by-product distribution and a degree of copper leached into the aqueous solution.

It was found that the activity of Cu/Y5 catalyst was generally higher than that of Cu/ZSM5 and that unlike Cu/ZSM5, Cu/Y5 catalyzed phenol oxidation more completely.