oa The control of Gas Hydrate formation using ionic liquids

Gas hydrates are crystalline solids consisting of three dimensional, hydrogen bonded water molecules (host), encapsulated with a guest molecule. [1] There are numerous possibilities for the molecules acting as the guests. The most common guests include methane, ethane, propane and carbon dioxide. They can be significantly problematic in the production of oil and gas. The 1930's marked the discovery, by Hammerschmidt, of the formation of hydrates in pipes. This formation can eventually cause a blockage in the pipeline, creating the risk of explosion, as the blockage may cause a high pressure and low pressure section of the pipe. This causes the hydrate to act as a high velocity solid which not only results in destruction to equipment but can also lead to loss of lives. [2] As the production of oil and gas moves to more extreme, hydrate favouring conditions, predominantly inhibition is the only viable option. Clathrate hydrate inhibitors are divided into three groups, thermodynamic inhibitors (THI), low dosage hydrate inhibitors (LDHI) and ionic liquids (IL). Ionic liquids have the potential to act as inhibitors but previous research has been restricted by the lack of design on the ionic liquids being experimented e.g ionic liquids chosen due to their commercial availability. There are many advantages to using ionic liquids, but in increasing their field application certain design criteria should be followed. The Ionic liquids used should be water soluble, form hydrogen bonds with water, relatively non-viscous, low toxicity, biodegradable and have minimal halogen content. The main aim of this work is to Design, Synthesise and Characterise ionic liquids within the criteria that will perform as hydrate inhibitors and to test the ionic liquids as both thermodynamic and kinetic inhibitors in the high pressure view cell and compare the performance with current commercial inhibitors.The initials experiments were performed to ensure the equipment was fully working and so the literature data for the blank test with no inhibitor and methanol 5 and 10 wt% were reproduced to verify thisAs can be observed from the graph, the literature data has successfully been repeated. This is also shows that the equipment is working and is operating to the desired needs of the project. Frequently imidazolium cations, particularly EMIM, are observed in the literature featuring ionic liquids as inhibitors. The next stage was to look at how effective these ionic liquids are, however, exchanging the halogen anion. The properties mentioned before suggest alcohol or ketone groups on the anion in order to maximise hydrogen bonding effectively increasing inhibition ability. This change would also help in making the ILs more environmentally friendly and lower the toxicity of them.