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Characterization of zirconia-magnesia-yttria materials used as catalysts for esters and alcohols fractions transformations by ketonization

Klimkiewicz R., Teterycz H., Sikora E., Rakoczy J., Biskupski A., Trawczyński J.

Polish Journal of Chemical Technology

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2005

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Vol. 7, nr 1

29-32

EN

In former publications the application of the monophase material Zr(0.89)-Mg(0.10)-Y(0.01)-O as a catalyst of the waste alcohol and ester fractions ketonization was described. In the present work various compositions of the Zr-Mg-Y-O type respecting the reaction group: Zr(0.89)-Mg(0.10)-Y(0.01)-O(CL) synthesized from chlorides, Zr-Mg-Y-O(SULPH) from zirconium sulfate, mixed oxide ZrO2+Y2O(3BOG) and its derivative Zr-Mg-Y-O(BOG) are characterized. The catalytic properties of the materials were characterized with the use of n-butanol test, isopropanol test, cyclohexene + H2 test as well as TPD NH3, and FT-IR (pyridine) spectroscopy. Zr-Mg-Y-O(SULPH) catalyst obtained from the sulfate precursor, as compared to Zr(0.89)-Mg(0.10)-Y(0.01)-O(CL), revealed a much lower selectivity of the reaction of the primary and secondary alcohols into ketones. The surfaces of Zr(0.89)-Mg(0.10)-Y(0.01)-O(CL) and ZrO2 + Y2O(3BOG) materials, although they contained comparable numbers of the Lewis acidic centers (164 and 126 žmol Py/g, respectively), differed considerably as for the selectivity in the reaction of n-butyl alcohol condensation: ZrO2,+Y2O(3BOG) was not a selective catalyst of the ketonization. Under the conditions of the cyclohexene + H2 test over ZrO2 + Y2O(3BOG) the reaction proceeded towards isomerization and cracking, while Zr(0.89)-Mg(0.10)-Y(0.01)-O(CL) catalyzed hydrogenation. The application of Zr-Mg-Y-O(BOG) material of the lower Lewis acidity (62 žmol Py/g) did not result in the higher selectivity of the ketonization. However, the result of the cyclohexene + H2 test changed. Thus, a considerable number of the Lewis acidic centers (such as ZrO2+Y2O(3BOG) was not the only necessary condition for the bimolecular condensation of the primary alcohols and/or aldehydes or for esters transformation. The search for materials should be conducted towards the syntheses of the catalysts of the dehydrogenation properties and containing in their structure oxygen vacancies which could form the Lewis acidic centers.

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Possibility of waste alcohols usage.

Klimkiewicz R., Grabowska H., Teterycz H., Syper L., Biskupski A., Rakoczy J.

Prace Naukowe Instytutu Chemii i Technologii Nafty i Węgla Politechniki Wrocławskiej. Konferencje

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2002

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Vol. 10, nr 57

223-227

EN

The application of a material designated as Sn-Ce-Rh-O, used up to now for the production of gas sensors, can be used as a catalyst for primary alcohols conversion to enable obtaining ketones as bimolecular condensation products. Thus, esters and aldehydes can also be substrates. In consequence, mixtures containing various alcohols, esters, aldehydes, secondary alcohols, and hydrocarbons can be processed. The content is consistent with waste mixtures of industrial origin (cyclohexanone production). The method enables conversion of such waste fractions into fractions with ketones predominating. The multicomponent content of the ketone fractions does not hinder their further utilization. There was carried out a ketonization of a waste alcohol fraction which contained n-pentanol (54%), cyclohexanone (11%), n-butanol (11%), cyclopentanol (8%), caproic aldehyde (3%), and other components. As a catalyst, there was used a tin-cerium-rhodium components, where the molar ratio of tin dioxide to cerium dioxide was 9:1, with Rh 0.05mol%. The reaction was carried out in a typical flow reactor at a temp. of 390 under atmospheric pressure and at a load of 1.0 h-1. The condensed reaction product contained 67% ketones, including 39% ketones derived from n-pentanol: di-Bu ketone (32%), Bu Pr ketone (5%), Bu pentyl ketone (2%), cyclohexanone (10%), di-Pr ketone (5%), and others.

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CeO2 oraz stabilizowany ZrO2 jako potencjalne katalizatory ketonizacji odpadowych alkoholi

Teterycz H., Klimkiewicz R., Grabowska H.

Chemia i Inżynieria Ekologiczna

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2002

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Vol. 9, nr 5/6

655-658

PL

CeO2 oraz ZrO2 domieszkowany MgO i Y2O3 zastosowano jako katalizatory w ketonizacji n-butanolu. Wobec obu katalizatorów wydajność i konwersja były zbliżone. Badania zmierzają do przeróbki odpadowych frakcji alkoholowych.

EN

CeO2 and also Zr)2 doped with MgO and Y2O3 were applied as catalysts in the ketonization of n-butanol. Over both catalysts the yields and conversions were similar. The research leads to the reprocessing of waste alcohol fractions.

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Utilization of acohol factions from the poduction of clohexanone by ketonization

Klimkiewicz R., Biskupski A., Grabowska H., Teterycz H., Syper L., Rakoczy J.

Polish Journal of Chemical Technology

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2001

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Vol. 3, nr 3

10-12

EN

The method of utilization of alcohol fraction containing mainly primary alcohols is proposed. The fraction is a waste product arising in the process of cyclohexanone manufacturing. Alcohols are converted into symmetrical and asymmetrical ketones. The reaction proceeds in a continuous manner in the gas phase at the temperature range of 330 - 450°C in a flow reactor with fixed bed containing Zr-Mg-Y-0 catalyst. After processing the initial fraction at the temperature of 420°C and with the load of lh exp -1, a ketone fraction containing mainly nonanone-5 (over 40%, which corresponds to 75% yield and 80% selectivity) was produced. Apart from nonanone-5 in the fraction were such ketones as heptanone-4, octanone-4, cyclohexanone and other; the total content of ketones in the obtained fraction was 58%.