Sharif Digital Repository

Monolithic nanocatalysts for naphta hydrodesulfurization process have been prepared and evaluated. Commercial cordierite monolith was used as a ceramic substrate. Initially, the monoliths were pretreated with nitric acid solution in order to increase specific surface area. After that, carbon nanotubes were grown through catalytic decomposition of methane over prepared monoliths. Finally, the CNT-coated monoliths were oxidized with ozone and an aqueous solution of H2O2. For the preparation of HDS Co-Mo nanocatalysts, the metal content of aqueous solution including cobalt nitrate, ammonium heptamolybdate were then impregnated onto the prepared supports. Next, samples of prepared supports and... 

In the past few decades, many attempts have been made to combine the benefits of homogeneous and heterogeneous catalysts. The immobilization of homogeneous catalysts onto the surface of heterogeneous supports is the result of such efforts. In this research, immobilized heterogeneous catalysts were designed and synthesized based on double network hydrogels, which produce from interpenetrating of two biocompatible and biodegradable polymer networks. In order to provide magnetic responsibility and easy separation of catalyst from the reaction mixture, the magnetic nanoparticles were dispersed onto the surface of double network hydrogel. Finally, various metal nanoparticles such as palladium and... 

Today, catalysts have shown the growing applications in chemical industries especially for drug synthesis. Using immobilized heterogeneous catalysts is a sensible way to benefit from advantages of both heterogeneous and homogeneous catalysts. In this regards, homogeneous catalysts are immobilized on to a solid support through various methods. However, low loading amount of homogenous part and subsequently insufficient catalytic activity are main limitations of immobilized heterogeneous catalysts. For this reason, polymeric supports have been introduced to immobilize metal ions or nanoparticles. These polymeric supports not only possess advantages such as anti-corrosive properties, simple... 

This study aims at synthesizing and investigating of heterogeneous catalysts for biodiesel production as an alternative to fossil fuel with the transesterification of oil and methanol. Three main sections of this thesis concern the synthesis of nano-catalysts, characterization analysis, and investigation of the transesterification reaction under different condition. Two series of heterogeneous catalysts, including different molar ratios of X%Li/Ca-La (X=0-7%) and Ca/Talc (Ca, 3Ca/1Talc, 1Ca/1Talc, 1Ca/3Talc, Talc) has been synthesized as active and stable catalysts to study the transesterification reaction of canola oil and methanol for biodiesel production. Prepared catalysts have been... 

The purpose of this study is to study heterogeneous nanocatalysts for the production of biofuels by the method of exchange of styrene using oil and methanol as a fossil fuel alternative. Preparation of nanocatalysts, performing characteristic tests and investigating the reaction in different operating conditions in the batch reactor has already been studied. Therefore, in this study, the production of biodiesel fuel using the trans-esterification of canola oil with nanocatalysts in the micro-reactor reactor will be discussed. Previously, a heterogeneous catalyst (lithium based on calcium-lanthanum) was constructed using a co-incineration method and a wet inoculum, and as active and stable... 

The aim of this project is to investigate and synthesize CaO-based nanocatalysts derived from chicken eggshell calcination with alkali metals and sodium-potassium compounds promoters used in the transesterification reaction of canola oil and methanol. Sections of this thesis include the synthesis of nanocatalysts, catalyst characterization tests, and investigation of reaction under optimal conditions. Two groups of catalysts containing different weight percentages of alkali metals based on CaO and 1 %wt sodium-potassium based on CaO with different weight percentages of these two elements were synthesized by wet impregnation method and used in the reaction under optimum condition. Catalyst... 

Ferrite spinels are very valuable as heterogeneous catalysts and have the ability to separate. In this dissertation, ferrite nanoparticles were synthesized by co-precipitation method and used in carbon-phosphorus and phosphorus-sulfur bond formation reactions. The structure of these compounds was investigated by different techniques. The ferromagnetic CuFe2O4 ferrite catalyst was expanded in the C-P bond formation reaction, resulting in a convenient and efficient method. Phosphorylation of alkenes was performed using a model reactant, dialkyl phosphite as a source of phosphorous compounds, and beta-ketophosphosphonates were synthesized. Beta-ketophosphonates are important intermediates for... 

In this thesis, a heterogeneous nanocatalyst based on graphene oxide was synthesized. To improve the graphene oxide, it was reacted with paraaminobenzoic acid and then metal salts (cobalt and manganese) were coated on it. The structure of the catalyst was confirmed by field emission scanning electron microscopy (FESEM), X-ray diffraction (XRD), quantitative X-ray diffraction (EDS) and infrared (FT-IR) spectroscopy. Finally, the catalytic properties of the catalysts were evaluated in the oxidation reaction of different alcohols in the presence of oxygen. In the presence of benzyl alcohols with lethal electron groups, the oxidation conditions are stricter and the reaction efficiency is lower.... 

consumption of which (especially azo dyes) have been increasing nowadays, causing the increase of textile wastewaters. Usually, these wastewaters contain an immense number of dyes, and if these dyes release in the environment especially in waters, they cause some problems, such as the change of watercolor as well as taste, and affect creatures' lives severely. Moreover, If the dyes are left untreated in aquatic ecosystems, they can remain in the environment for a very long time, resulting in harmful and irreversible effects. Azo dyes are classified as mono, di-, three, azo dyes due to their bonds. Because dyes are increasingly used, nowadays, different methods are developed for the treatment... 

The aim of this project is to fabricate and study heterogeneous CaO-based nanocatalysts with lithium and zinc enhancers for the esterification reaction of rapeseed oil and methanol to produce biodiesel as a renewable and alternative fuel for fossil fuels. Is. First, Zn-Li / CaO catalysts with weight ratio Li: Zn: CaO, 2: 2: 7 and by combining different percentages of Li100% promoter, Li75% -Zn25%, Li50% -Zn50%, Li25% -Zn75%, 100% Zn were made on the basis of CaO by wet inoculation. Characterization tests to evaluate the structure and characterization such as X-ray diffraction (XRD) spectroscopy, scanning electron microscopy (SEM) and X-ray diffraction (EDX) spectroscopy, Bruner-Emmett-Teller...