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The main purpose of this study is the oxidation of carbon monoxide to carbon dioxide in the presence of copper catalyst.  This odorless gas needs to be removed somehow because it is toxic. Oxidation methods include carbon dioxide oxidation and hydrogenation.  At present, the second method is interesting for researchers as a key technology to produce clean fuels and chemicals.  Copper catalyst was selected because of its cheapness and suitable activity in the carbon monoxide oxidation reaction.  In this study, the effect of different bases on product selectivity and feed conversion rate was investigated.  In this dissertation, first copper nanoxides were prepared by co-precipitation and microemulsion method and then the final catalyst was obtained by wet inoculation (copper on different bases).  Catalysts are evaluated in terms of physical and chemical properties, and in certain operating conditions of temperature (100-400 °C), pressure (1 atm), feed volume ratio (O2</sub> / CO / H2</sub> / N2</sub> = 2/2/5/91 and GHSV= 1.5-6 nl.h-1.gCat-1 valley fixed bed reactor system was tested.  The results of the reactor test show that TiO2</sub>-based copper nanocatalyst has a higher rate of carbon monoxide conversion and selectivity.  Increasing the lanthanum enhancer to the catalyst structure increases the conversion rate of carbon monoxide and the selectivity of carbon dioxide.

Hypothesis: 

Despite the wide application of nanofiltration (NF) membranes in forward osmosis (FO) process, one of the most important challenges of this process is the internal concentration polarization (ICP) phenomenon. Different methods have been investigated to reduce the effect of this undesirable phenomenon and it is suggested that one of these methods is loading of hydrophilic nanoparticles in the membrane structure. In this study, SiO2/ZIF-8 nanoparticles were used to improve the structure and performance of polyethersulfone membranes (PES) in FO process.

At first, polyethersulfone membrane was synthesized by phase inversion method. In the next step, ZIF-8 and SiO2/ZIF-8 nanoparticles as filler were synthesized at room temperature. Thin film composite membranes were prepared by the interfacial polymerization (IP) of two reactive organic (TMC) and aqueous (MPD) monomers. Finally, the produced membranes and nanocomposite were characterized by contact angle, FTIR spectroscopy, X-ray diffractometry (XRD), field emission scanning electron microscopy (FESEM), and porosity measurements. Also, the performance of all membranes composed of at least two different components was investigated using reverse and forward osmosisi processes.

The outcomes demonstrated that the presence of a small amount of SiO2/ZIF-8 nanoparticle in the membrane led to an increase in the membrane hydrophilicity and porosity, and also improved the water flux and rejection of the FO. The water flux of TFN FO membrane was reported to increase remarkably from 15.23 to 25.13 L/m2.h when 10 mM NaCl and 2 M NaCl salt were utilized as feed solution (FS) and draw solution (DS), respectively. The improvement in FO water flux was ascribed to the lower S parameter of modified PES sublayer and the reduction of internal concentration polarization (ICP).