New catalysts have been developed by combining Pd-based bimetallic catalysts and zeolite supports to achieve higher selectivity for the selective hydrogenation of acetylene in a stream containing excess ethylene at relatively low temperatures (300-339K). Low-temperature hydrogenation offers the opportunity of using competitive adsorption to achieve preferential hydrogenation of acetylene. Previous work for this has found that bimetallic catalysts favor low temperature hydrogenation. Results from many other groups have also shown that Pd is a good catalyst for the selective hydrogenation of alkynes in excess ethylene. Therefore the strategy of the present work was to modify Pd catalysts and embed bimetallic particles in an environment that is highly selective for acetylene hydrogenation. Cation-pi interaction offers the potential for selective adsorption of acetylene. We used the ion-exchanged zeolite for the support of the bimetallic catalysts. The zeolite structure should have multiple dimensions and contain large pores, in order to house the bimetallic particles inside the pores. In this work, we focus on beta-type zeolites. Flow reactor studies using GC, batch reactor studies using FTIR, and TPR evaluation have been utilized for this project. It was found that the Pd-Ag bimetallic catalyst had a much higher selectivity for acetylene hydrogenation in excess ethylene than either Pd or Ag, while the Pd-Ni bimetallic catalyst behaved similarly to the Pd catalyst. Modeling of reactions in FTIR also showed that there was a small difference in the rate constant and equilibrium constant of Pd/beta-zeolite and Pd-Ni/beta-zeolite. The zeolite support also exhibited enhanced activity for the low temperature hydrogenation of acetylene.

In this study the liquid phase citral hydrogenation reaction over zeolite supported monometallic and bimetallic Ni and Pt catalysts was studied. The zeolite support materials were Na-Y, Na-, Na-Mordenite, MCM-41, and Clinoptilolite. The catalysts were prepared by impregnation and co-impregnation techniques. Catalytic activity and selectivity tests were performed in a semi-batch reactor at 80ʻC temperature, 6 bar pressure and 600 rpm stirring speed with 0.25 g catalyst. The characterization studies showed that the structures of support materials were preserved during impregnation and co-impregnation. The Ni and Pt contents of the catalysts was around 8.5 % and 5 %, respectively while the Sn content changed between 0.46 and 4.10 %. The activity of the catalysts and product distribution were affected by type of active metal and type of support. The major product over monometallic and bimetallic catalysts was citronellal. The Ni/Na-Y catalyst gave the maximum yield of desired products, unsaturated alcohols and citronellal, (93 %) and citral conversion (>99 %) among the monometallic catalysts. The most selective monometallic Pt catalyst to desired products was Pt /MCM-41 with a yield of 40 %. Addition of Sn increased the unsaturated alcohol formation and decreased the acetal formation. The activity of the Ni catalyst was generally decreased while the activity of the Pt catalyst was improved. The amount of unsaturated alcohols increased with Sn/Sn+Ni ratio for bimetallic Ni catalysts. The highest yield of desired products was obtained with Ni/Na-Y (93 %) and with Ni-Sn/MCM (80 %) among monometallic and bimetallic catalysts.

After three meetings in Poitiers, France, the 4th International Symposium on Heterogeneous Catalysis and Fine Chemicals was held under the auspices of the New Swiss Chemical Society in Basel, Switzerland. Fundamental as well as applied contributions on the use of heterogeneous catalysis for the preparation of fine chemicals were presented and discussed.The program consisted of 4 plenary lectures, 28 oral contributions and around 90 posters covering a broad range of reactions and catalytic aspects. 82 of these contributions are collected in the present proceedings, grouped into the following 8 topical areas:- Industrial and engineering problems (7 contributions)- Alkylation and acylation reactions (11 contributions)- Enantio- and diastereoselective hydrogenation reactions (9 contributions)- Chemoselective hydrogenation reactions (12 contributions)- Oxidation reactions (14 contributions)- Immobilized and encapsulated complex catalysts (12 contributions)- Zeolite and clay catalysts (12 contributions)- Miscellaneous topics (5 contributions)

This thesis offers novel methods for catalyst and process design for the selective hydrogenation of acetylene and 1,3-butadiene. The author predicts the properties of supported Pd–Ni bimetallic catalysts using density functional theory (DFT) calculations and temperature-programmed desorption (TPD). The excellent correlation between model surfaces and supported catalysts demonstrates the feasibility of designing effective bimetallic catalysts for selective hydrogenation reactions. The author also proposes a method for designing non-precious metal catalysts to replace precious metals. She modifies the process of selective hydrogenation of acetylene by coupling the selective adsorption to the selective hydrogenation in the liquid phase, as a result of which the ethylene selectivity is greatly improved and heat transfer is greatly enhanced. Lastly, by analyzing the mechanism of liquid-phase hydrogenation, the author proposes a multi-stage slurry bed reactor for industrial applications.“/p>