Pincer complexes moieties have attracted much attention in the past years. They have been proved that they are highly active catalysts in many different known transition metal-catalyzed organic reaction and some unpredictable organic transformation. In this thesis, we will use PN3P Cobalt pincer complex in two different applications. The first application is the unpresented Cobalt-catalyzed hydrogenation of nitriles to secondary imines. The selective hydrogenation of nitriles into secondary imines is a very challenging task and the catalysts play a very important role in the reaction and the selectivity. Herein in the thesis, we report the first selective hydrogenation of nitriles to secondary imines catalyzed by a well-defined and accessible PN3P cobalt pincer complex. Our results show different selectivity compared with the known PNP cobalt catalytic system during the nitriles hydrogenation. A set of aliphatic and aromatic nitriles are hydrogenated to the secondary imine under relatively mild conditions. The second application is the alkylation of nitriles with alcohols using PN3P cobalt pincer complex. The alcohol is being used here as alkylating agent in state of using toxic alkyl halides or excess amount of base to avoid any salt waste. The cobalt pincer complex work as catalyst for transformation that undergoes alkylation via hydrogen transfer pathways. The beauty of this reaction that it is delver water as the only byproduct. A different nitriles and alcohol are tolerated in this reaction.

Two different catalysts (bis[N-(3-tert-butylsalicylidene)-pentafluoroanilinato] titanium (IV) dichloride and [1-(8-quinolyl)indenyl] chromium (III) dichloride catalysts) activated with aluminoxane based co-catalysts (MAO, PMAO, MMAO12 and MMAO3A) have been evaluated in the polymerisation of ethylene leading to UHMWPE having a reduced number of entanglements between the chains. The effect of a co-catalyst modifier (BHT) on the catalytic systems and the resulting polymers is also addressed. Both catalysts are capable to promote the synthesis of UHMWPE having a reduced amount of entanglements in the conditions used. Uniaxial solid-state deformation of UHMWPE samples of different molar masses have been evaluated and related with the entanglement state of the polymers synthesised. A clear relationship between some mechanical properties and the molar mass/entanglement density of the polymers synthesised has been found.

Abstract Isopropyl alcohol¡]IPA¡^and toluene are extensively used in industry as solvents. They are all highly toxic to animals and humans. Accordingly, IPA and toluene are strongly associated with problems of VOCs. In first step catalytic incineration was adopted to decompose IPA and toluene in laboratory, and the second step for a pilot-scale regenerative catalytic oxidizer ¡]RCO¡^were adopted to decompose mixture VOCs in real soil herein. The screening test of catalytic activity and the influences of the operational parameters on IPA and toluene removal efficiencies were widely discussed through catalytic incinerations of IPA and toluene in laboratory. The more effective and cheaper catalysts through above discussions of catalytic incineration were selected. And they were utilized in an pilot scale RCO as follows to investigate their performance in VOCs oxidation and RCO operations in THC removal of contamination soils. The achievements of this study are summarized as follows: ¡]1¡^Cu/Mn and Cu/Co gravel catalytic incinerations of isopropyl alcohol The results demonstrated that 10 wt% Cu0.6Co0.4 catalyst was the most effective because the CO2 yield reached 95 % under the following operating conditions; a temperature of 425oC, an inlet IPA concentration of 2500 ppm, an oxygen concentration of 21%, and a space velocity of 13500 hr-1. Additionally, the stability test results indicated that the 10 wt% Cu0.6Co0.4 catalyst exhibited excellent stability at both low and high conversion of IPA. ¡]2¡^20% Cu/Mn aluminum oxide catalytic incinerations of toluene The conversion for toluene reached 95% when the Cu/Mn catalyst was used with a metal ratio of 1:1 and 20% loading at 350¢XC, an influent toluene concentration of 1000 ppm, oxygen concentration of 21%, a space velocity of 12000 hr-1, and relative humidity of 26%. The long-term test was proceeded for seven days at a constant influent toluene concentration of 1000 ppm, constant oxygen concentration of 21%, constant space velocity of 12000 hr-1 and constant relative humidity of 26%. The SEM results indicated the Cu/Mn catalyst was quite stable at 350¢J. ¡]3¡^RCO testing for a copper/manganese catalyst of gaseous toluene The Cu/Mn (20wt%) catalyst was selected as the best one, because it converted 95% of the toluene at 400¢J. The results also indicating that the Cu/Mn catalyst was quite stable at 400¢J. (4) RTO treatment of VOCs with SVE system The conversion for VOCs reached 80% at 900¢XC, an influent VOCs concentration of 450-2000 ppm and a gas flow rate of 0.5 m3/min.The Thermal Recovery Efficiency¡]TRE¡^was approximately 86-90% in a RTO operated at 800-900¢J. (5)RCO treatment of VOCs with SVE system¡]10 wt% Cu0.6Co0.4 gravel catalyst¡^ The 10 wt% Cu0.6Co0.4 gravel catalyst was the poverty active, because it converted 65% of the VOCs by SVE system operated at 650¢J. (6)RCO treatment of VOCs with SVE system¡]20% Cu/Mn aluminum oxide catalytst¡^ The 20% Cu/Mn aluminum oxide catalytic was the best choice, because it converted 95% of the VOCs at 650¢J, an influent VOCs concentration of 450-10000 ppm and a gas flow rate of 0.5-1.5 m3/min. The SEM results indicated that the conversion of VOCs decay did not clearly vary at 650¢J, also indicating that the Cu/Mn catalyst selected was quite stable. The TRE was approximately 90% in a RCO¡]20% Cu/Mn aluminum oxide catalytic¡^operated at 650¢J. (7)RCO treatment of VOCs with SVE system¡]20% Cu/Mn gravel catalytst¡^ The 20% Cu/Mn gravel catalytst was the best selection , because it converted 95% of the VOCs at 600¢J, an influent VOCs concentration of 450-10000 ppm and a gas flow rate of 0.5-1.5 m3/min. The SEM results indicated that the conversion of VOCs decay did not clearly vary at 600¢J, also indicating that the Cu/Mn catalyst selected was quite stable. The TRE was approximately 90% in a RCO¡]20% Cu/Mn gravel catalytic¡^operated at 600¢J.

In 1972 Fujishima and Honda conceptualised a photoelectrochemical cell for hydrogen generation via PEC water splitting. Hydrogen as a clean energy carrier provides environmentally friendly energy storage solutions or can fuel certain applications. This idea has since then been further built upon with new materials and combinations with the aim of improving efficiency. In this project n-type cubic silicon carbide thick layers were grown by a sublimation method and characterised for water splitting performance. A generated photo-current density of 0.45 mA/cm2 was measured with no bias between the working and counter electrodes.

This master thesis deals with the direct synthesis of polymers from lactic acid. The theoretical part focuses on both natural and synthetic ways of production the lactic acid monomer, their advantages and properties. Furthermore, the theoretical part focuses on the synthesis of poly(lactic acid) (PLA) from lactide, and direct polycondensation from lactic acid discussing about influences of catalysts, co-catalysts as well as chain extenders. The experimental part focuses on the synthesis of PLA polymers and co-polymers wherein investigates suitable catalysts, reaction medium for azeotropic dehydration and co-catalyst influence on products. Thermal and analytical analysis of PLA polymers are mentioned at the end of the experimental part.

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