With World oil demand increasing in the face of limited supplies, increasing attention is turning towards non-conventional oil sources as a means to relieve the pressure exerted on conventional stocks. However, non-conventional oils are hard to extract, process and transport. Several technologies are already at work with differing levels of success, recovery ranging from as low as 5% through to more than 70%. This paper reviews the range of Enhanced Oil Recovery techniques, broadly classified into either thermal or non-thermal methods, and their applicability to the extraction of heavy oils and bitumens. Advantages and disadvantages are presented in terms of their recovery factors, requirements, limitations and economics. The potential benefits of additional downhole catalytic upgrading of heavy oils are also explored.

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Hydrolysis of the DMF or DEF solvent influences the nature of the product observed in the reaction between zinc(II) nitrate and 1,4-benzenedicarboxylic acid, with dialkylammonium cations able to template the formation of anionic networks.Coordination networks, or metal-organic frameworks (MOFs) are currently attracting a tremendous amount of interest. 1,2 This is largely a result of their potential for porosity, and the implications of this in applications such as gas storage. 3,4 Some of the most spectacular results in this area have arisen from the Yaghi group. 5-8 They have reported a number of interesting structures, and impressive adsorption properties for compounds such as [Zn 4 (m 4 -O)(m-bdc) 3 ] (bdc 22 5 1,4-benzenedicarboxylate, terephthalate), which they refer to as MOF-5. Although the effectiveness of this material in hydrogen absorption has recently been queried, 9 MOF-5 and related compounds are currently receiving considerable attention within the porous material field. [10][11][12] From a chemical perspective, the zinc-bdc 22 system is far from straightforward. [Zn 4 (m 4 -O)(m-bdc) 3 ] can be prepared from Zn(NO 3 ) 2 ?6H 2 O and H 2 bdc under solvothermal conditions 13 or at room temperature. 14 In addition to [Zn 4 (m 4 -O)(m-bdc) 3 ], a number of other compounds have been prepared from Zn(NO 3 ) 2 ?6H 2 O and H 2 bdc. [15][16][17] In this paper we report how the presence of water in the solvent is crucial in influencing the product from the reaction between Zn(NO 3 ) 2 ?6H 2 O and 1,4-benzenedicarboxylic acid in either DMF or DEF.When Zn(NO 3 ) 2 ?6H 2 O and H 2 bdc were heated in fresh DEF at 95 uC for 3 h, small colourless crystals precipitated from the solution. These were shown to be [Zn 4 (m 4 -O)(m-bdc) 3 ]?3DEF 1 (i.e. solvated MOF-5) by a combination of X-ray single-crystal and powder diffraction experiments, the latter of which produce identical results to those simulated from the previously reported crystal structure. 5 When Zn(NO 3 ) 2 ?6H 2 O and H 2 bdc were heated under the same conditions, in DEF that had been in the laboratory for several weeks, small colourless crystals were again isolated. However, in this case, the product was shown by a combination of X-ray single-crystal and powder diffraction experiments to be exclusively the previously unreported compound [NH 2 Et 2 ] 2 [Zn 3 (mbdc) 4 ]?2.5DEF 2.The structure of 2 is based on bdc 22 anions bridging between linear Zn 3 (m-O 2 CR) 6 secondary building units (SBUs). The central Zn(1) atom has a distorted octahedral geometry, and is k 1 -coordinated to six carboxylates. The two symmetry-related peripheral Zn(2) atoms exhibit distorted tetrahedral geometry, and are each k 1 -coordinated to four carboxylates. Three of these groups bridge to Zn(1), though one adopts the m-k 1 O,k 1 Ocoordination mode rather than the more common m-k 1 O,k 1 O9-mode employed by the other two. The six bridging carboxylates radiate from the Zn 3 (m-O 2 CR) 6 SBU at approximately 60u angles, leading to the construction of a layer structure with tri...

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