نبذة مختصرة : The dissertation is based on the three above mentioned projects. Different types of reactors for heterogeneous catalysis were applied in this work – fixed and fluidized bed rectors as well as a riser reactor. Many parameters as e.g. contact times, temperature control, catalyst regeneration procedure etc. can be varied and adjusted to the special reaction requirements. Correct reactor choice is the decisive factor for the optimal reaction performing. One of the objectives of this work is to find a way to produce the “green” reagent, dimethyl carbonate (DMC), through transesterification of propylene carbonate (PC) and methanol in the vapor phase. The importance of DMC for the development of variety of green syntheses is widely described. The reaction conditions and the catalyst preparation procedure were optimized. Catalyst screening for the dimethyl carbonate production reaction performing in the liquid phase was done. CaO showed best results as well as superbase MgO/Na/NaOH. PC conversion of around 70 mol.% with 99 mol.% DMC and PG selectivity was achieved. However, reaction performing in the liquid phase doesn’t allow effective reuse of the catalyst. For this reason it was attempted to perform this reaction heterogeneously in fixed bed reactor in the vapor phase and at ambient pressure. Catalyst screening in gas phase was done. Y-zeolites showed highest activity. It was detected that H- and NH4-form of Y-zeolites are suitable for PC/methanol transesterification. In contrast to this Na- and Ca- form lead to the strong side products formation. An optimization of the reaction conditions as well of the catalyst preparation method led to the growing DMC selectivity and conversion. Many parameters were found to have strong influence on the DMC selectivity and only its narrow values range can be used for the effective reaction performance. Another environmental problem is considered in this work. During crude oil production considerable amount of associated gas is coming out. Due to the difficulties of its use – primary because of the transportation problem – it is just burning out on the wells. This leads to the enormous loss of the energy. One of the approaches to utilize the associated gas is the direct conversion of methane to the liquid hydrocarbons like benzene and toluene. Molybdenum loaded HZSM-5 was described in the literature as a suitable catalyst for this reaction. Investigations of Mo/HZSM-5 catalyst for the heterogeneous dehydroaromatization of methane were performed in this work. Comparison of fixed and fluidized bed reactors as well as influence of different factors was investigated and optimal conditions for performing of the reaction were found. Several reaction optimizations like WHSV level, reaction temperature, carbon dioxide addition were performed in the fixed bed reactor at ambient pressure. The methane WHSV level was found to be optimal in the range of 1.5-2.0 h-1. Increasing of the temperature favors the desired aromatic formation but causes strong irreversible catalyst deactivation. Temperature optimum lies in the range 700-725°C. Detrimental effect of the carbon dioxide addition was detected. Methane conversion as well as aromatic formation was significantly suppressed by addition of 3% CO2 to the methane feed. Moreover use of the fluidized bed reactor for methane dehydroaromatization at ambient pressure was studied. Around 15% more aromatic yield compare to the fixed bed reactor were achieved in the fluidized bed reactor. However, catalyst underwent strong deactivation already after several hours at the fluidized conditions. The reasons for the deactivation were investigated. Significant loss of crystalline structure and molybdenum leaching were detected. Strong reducing of the particles size distribution was observed too. Mechanical stability of the particles has to be improved to use this catalyst in fluidized bed reactor in large scale. Furthermore some applied questions of a new route to styrene production as developed by DOW Chemicals Co. were investigated. During the operation of a plant some problems in the reaction performing appeared. It concerns e.g. source of the oxygen in the reaction and its dependence from the gas residence times and temperature. The influence of the ethane and water presence in the feed on the catalyst activity was investigated. The reaction was performed heterogeneously in a riser reactor. Unusual strong carbon dioxide formation during this process was explained through the oxygen in the catalysts pores and its sequent oxidation during the reaction. Use of only nitrogen as a feed in a blank experiment as well as argon flushing of the catalyst prior to the experiments didn’t lead to the reducing of the oxygen content in the product mixture. High reaction temperature and long gas residence times favor the increased side products formation. Positive effect of the water presence in the feed was observed.
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