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This thesis describes the design, synthesis and characterisation of a series of novel metal-organic frameworks constructed from Cu(II) paddlewheels and polydentate aromatic carboxylate ligands. Gas sorption applications of these porous materials have been studied, with an emphasis on hydrogen storage. The effects of cage wall functionalisation within the frameworks, internal BET surface areas and pore volumes, and open Cu(II) sites on H2 adsorption by these materials are investigated. Chapter 1 introduces the current status of H2 storage in metal-organic framework materials. Extended metal-organic structures exhibiting large surface areas and high total pore volumes are favourable for H2 storage at high pressures and cryogenic temperatures. The strategy of utilising metal-organic polyhedra as secondary building blocks in the assembly of highly porous frameworks with high structural stability is discussed. Chapter 2 describes the synthesis of a highly porous (3,24)-connected metal-organic polyhedral framework (denoted NOTT-112) constructed from a nanosized hexacarboxylate linker and {CU2(COO)4} paddlewheels. The framework of NOT- 112 is composed of three types of metal-organic polyhedral cages: cuboctahedra, truncated tetrahedra and truncated octahedra. Desolvated NOTT-112 shows a very large apparent surface area of 3800 m2 g-l (BET) and high H2 storage capacity of 7.07 wt% (excess) at 35 bar at 77 K (total H2 uptake of 10.0 wt% at 77 bar and 77 K), making it one of the best materials for H2 storage at cryogenic temperatures and high pressures. In Chapter 3, neutron powder diffraction (NPD) studies on D2 (deuterium)-loaded NOTT-1l2 give the insight into the mechanism of H2 adsorption in this polyhedral MOF with coordinatively unsaturated Cu(II) sites. NPD experiments reveal that the exposed Cu(II) sites within the smallest cuboctahedral cages in NOTT-112 are the first and strongest binding sites for D2 in this material giving an overall discrimination between the two types of exposed Cu(II) sites within one {CU2} paddlewheel unit. Thus, NPD studies provide, for the first time, direct structural evidence demonstrating that a specific geometrical arrangement of exposed Cu(II) sites, in this case within a [Cu24(isophthalate)24] cuboctahedral cage, strengthens the interactions between D2 molecules and open metal sites. In the second part of this chapter, partially deuterated MOF NOTT-112-d13 was synthesised for inelastic neutron scattering experiments. In Chapter 4, four isostructural metal-organic polyhedral cage based frameworks (denoted NOTT-l13, NOTT-114, NOTT-115 and NOTT-118) with (3,24)-connected topology have been synthesised by combining hexacarboxylate isophthalate linkers with {CU2(COO)4} paddlewheels. All four frameworks have the same cub octahedral cage structure constructed from 24 isophthalates from the ligands and 12 {CU2(COO)4} paddlewheel moieties. The frameworks differ only in the functionality of the central core of the hexacarboxylate ligands with phenyl, trimethylphenyl, phenyl amine and triphenylamine moieties in NOTT-118, NOTT-113, NOTT-114 and NOTT-115, respectively. The desolvated framework materials shows high BET surface areas of 3265, 2970, 3424 and 3394 m2 g-l for NOTT-118, NOTT-l13, NOTT-114 and NOTT-115, respectively. Desolvated NOTT-l13 and NOTT-114 show high total H2 adsorption capacities of 6.7 wt% and 6.8 wt% at 77 K and 60 bar, respectively. Desolvated NO TT -118 and NOTT -115 have significantly higher total H2 uptakes of 8.0 wt% and 7.5 wt% under the same conditions, respectively. Analysis of the heats of adsorption (QsD for H2 reveals that with a triphenylamine moiety in the cage wall, desolvated NOTT-115 shows the highest value of Qs/ for these four materials indicating that functionalisation of the cage walls with more aromatic rings can enhance the H2/framework interactions. In contrast, measurement of Qs/ reveals that the amine substituted tris-alkynylbenzene core used in NOTT-114 gives a notably lower H2/framework binding energy. NOTT-112 to NOTT-115 also show high CH4 adsorption capacities (104-124 cm\STP) cm -3) at 20 bar and room temperature. The amine-functionalised NOTT-114 exhibits strong CO2-framework interaction and high CO2 storage capacity of 22.9 mmol g-1 at 20 bar and 298 K. Chapter 5 describes the linker expansion strategy used in construction of highly porous MOFs. Ultrahigh porosity can be achieved by expansion of the C3-symmetric hexacarboxylate linkers in the polyhedral frameworks. Two isostructural noninterpenetrated (3,24)-connected frameworks NOTT-116 and NOTT-119 have been synthesised based on elongated poly-aromatic hexacarboxylate linkers. Both frameworks of NO TT -116 and NOTT -119 consist of mesoporous cages with diameters up to ~ 3 nm. These two mesoporous materials show good thermal stability and can be fully desolvated without framework collapse by traditional activation method (heating the samples under vacuum). Desolvated NOTT -116 exhibits a significantly high BET surface area (4664 m2 g-I) and a high H2 adsorption capacity (saturated excess H2 uptake of 6.4 wt% at 77 K; total uptake of 9.2 wt% at 77 K and 50 bar). NO TT -119 shows a lower specific surface area of 4118 m2 g -I and a lower saturated excess H2 uptake of 5.6 wt% at 77 K, but a larger pore volume of 2.32 cm3 g-l, leading to a high total H2 uptake capacity of 9.2 wt% at 77 K and 60 bar. Another Cu(II) based MOF NOTT-120 constructed from a hexacarboxylate linker as large as 3.0 nm shows ultrahigh porosity with ultrahigh total pore volume of 2.81 cm3 g-l. Chapter 6 summarizes the H2 storage properties of the (3,24)-connected frameworks and draws an overall conclusions from this study.

The application of solid adsorbents for gas separation in pre-combustion carbon capture from gasification processes has gained attention in recent times. This is due to the potential of the technology to reduce the overall energy penalty associated with the capture process. However, this requires the development of solid adsorbent materials with large selectivity, large adsorption capacity, fast adsorption kinetics for CO2 coupled with good mechanical strength and thermal stability. In this work, results on CO2 adsorption performance of three different types of adsorbents; a commercial activated carbon, phenolic resin activated carbons and zeolite templated carbons have been reported at atmospheric and high pressures conditions. The commercial activated carbon was obtained from Norit Carbons UK, the phenolic resin activated carbon was obtained from MAST Carbon Ltd., while the templated carbons were synthesized in the laboratory. A commercial activated carbon was used as bench mark for this study. Surface modification of these carbons was also undertaken and their CO2 uptake measurements at ambient and high pressure conditions were recorded. The commercial and templated carbons were modified by functionalising with amine group, while the phenolic resin carbon was modified by oxidation. The textural properties of the adsorbents was examined using the Micromeritics ASAP, while the CO2 adsorption capacities were conducted using the thermogravimetric analyser (TGA) and the High pressure volumetric analyser (HPVA). Textural properties of synthesized templated adsorbents were seen to depend on the textural characteristics of the parent material. The β-type zeolite produced the carbons with the best textural property. Increase in activation temperature and addition of furfuryl alcohol (FA) enhanced the surface area of most of the templated carbons. The textural property of all the adsorbents under study was seen to differently affect the CO2 uptake capacity at atmospheric (0.1 MPa) and high pressure conditions (up to 4 MPa). Micropore volume and surface area of the commercial activated carbons, phenolic resin activated carbons, and the templated carbons greatly influenced the adsorption trends recorded at ambient conditions. Total pore volumes positively influenced adsorption trend for templated carbons, but not the phenolic resin activated carbons at ambient and high pressure. This also positively influenced the adsorption trend for the commercial activated carbons, but at ambient conditions only. The surface area and the micropore volume have no effect on the adsorption trends for the templated carbons and the commercial activated carbons at high pressure conditions. However, these played a positive role in the adsorption capacities of the phenolic resin activated carbons at the same experimental conditions. Micropore volume and surface area of adsorbents play a major role on the adsorption trends recorded for the modified adsorbents at ambient conditions only. No trend was recorded for adsorption capacities at high pressure conditions. Only the oxidized phenolic resin activated carbon showed a positive adsorption trend with respect to total pore volume at high pressure condition. The amine modified commercial activated carbon showed no positive adsorption trend with respect to the total pore volume at both ambient and high pressure conditions, while the amine modified templated carbon showed no adsorption trend with respect to the textural properties at ambient and high pressure conditions. CO2 uptake measurements for the modified and unmodified templated carbon and phenolic resin carbon, were observed to be higher than those of the commercial activated carbon at ambient and high pressure conditions. Maximum CO2 uptake was recorded at 25 oC. At ambient pressure, the phenolic resin carbon (MC11) showed the highest CO2 uptake of approximately 3.3 mmol g-1, followed by the commercial activated carbon (2.4 mmol g-1), then, the templated carbon (2.4 mmol g-1). At high pressure, the templated carbons (β-AC7-2%) showed the highest CO2 uptake (21.3 mmol g-1), followed by phenolic resin carbon (MC4 - 12.2 mmol g-1), and the commercial activated carbon (6.6 mmol g-1). When samples were modified, the amine modified templated carbon and oxidized phenolic resin carbon showed the highest CO2 uptake of 2.9 mmol g-1 each at ambient pressure, followed by the commercial activated carbon (2.7 mmol g-1). At high pressure conditions, the oxidized phenolic resin carbon showed the highest (10.6 mmol g-1) uptake level, followed by the templated carbon (8.7 mmol g-1), and commercial activated carbon (6.5 mmol g-1).

La production de gaz à partir de réservoirs de stockage souterrains en aquifère est parfois associée à l'érosion de particules solides issues de la matrice rocheuse. Ces venues de solides engendrées par l'écoulement de gaz peuvent causer des dommages aux équipements sur site amenant l'opérateur à limiter, voire à stopper, la production des puits. L'injection de polymères hydrosolubles (polyacrylamide linéaire ou microgels) est une solution très efficace pour réduire et, dans certains cas, stopper la production de solides comme l'ont montré les résultats des essais réalisés en France sur des réservoirs de Storengy - GDF Suez.Une étude expérimentale a été réalisée pour améliorer la compréhension des mécanismes à l’origine de l’efficacité des traitements polymères et améliorer leur performance. Les essais ont permis d’identifier et de quantifier deux effets distincts des traitements sur les venues de solides : la consolidation inter-granulaire et le recouvrement des pores par le polymère. Il a, ainsi, été mis en évidence l’impact de la couche de polymère adsorbé sur la mobilisation des particules colloïdales se trouvant à la surface des pores (appelées fines) et celui de la formation de liaisons solides entre des particules non cohésives sur la (re)consolidation de la matrice rocheuse. Dans sur le premier cas, le polymère agit, sous un angle préventif, comme une barrière physico-chimique empêchant le détachement des fines pouvant former le ciment inter-granulaire et l’efficacité des traitements est fonction de la proportion de surface de pores recouverte par le polymère. Dans le second cas, le polymère prend la place du ciment délité ; l’efficacité et la durabilité des traitements dépendent alors des propriétés mécaniques des liens solides inter-granulaires formés après assèchement des ponts capillaires / Gas production from underground geological reservoirs in aquifers is sometimes associated with the erosion of solid particles from the rock matrix. These solids venues generated by the gas flow can cause damages to the equipment on site leading the operator to limit or stop the production of wells. The injection of hydro-soluble polymers (linear polyacrylamide or microgels) is one of the promising techniques employed today to reduce and, in some cases, stop the production of solids as demonstrated by the results of tests conducted in France on reservoirs of Storengy - GDF Suez.An experimental study was conducted to better understand the mechanisms underlying the performance of polymer treatments and to increase their efficiency. Two main aspects have been experimentally evidenced: sand grains consolidation and polymer coating of the pore surface. Tests were carried out to accurately assess the impact of the adsorption of polymer on the mobilization of particles (called fines) and a comprehensive study was conducted showing the properties of treatments to (re)consolidate the rock matrix. In the first case, the polymer acts as a physicochemical barrier preventing the detachment of fines that can form the inter-granular cement and the effectiveness of treatments is based on the proportion of pores surface covered by the polymer. In the second case, the polymer takes the place of cleaved cement; the effectiveness and durability of treatments thus depend on mechanical properties of the inter-granular solids bounds formed after drying of capillary bridges