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Gold/Mining/Energy : Arcon Energy (MIDL Presently) The Ultimate Sleeper -- Ignore unavailable to you. Want to Upgrade?

To: Jay Lowe who wrote (1721)	5/30/1998 11:29:00 PM
From: Jay Lowe	Respond to of 4142

What follows below is a discussion of fuel composition factors and a list of Research Octane Blend Numbers (RON) for various additives ... along with some other funny numbers from the GasFAQ. The interesting part is that generic ethanol is listed with a RON = 129 ... compared to Arcon's DF-144 which according to the independent tests is considerably higher. Where is Gordon when you need him? --------------------- 4.13 What is a typical composition? There seems to be a perception that all gasolines of one octane grade are chemically similar, and thus general rules can be promulgated about "energy content ", "flame speed", "combustion temperature" etc. etc.. Nothing is further from the truth. The behaviour of manufactured gasolines in octane rating engines can be predicted, using previous octane ratings of special blends intended to determine how a particular refinery stream responds to an octane-enhancing additive. Refiners can design and reconfigure refineries to efficiently produce a wide range of gasolines feedstocks, depending on market and regulatory requirements. There is a worldwide trend to move to unleaded gasolines, followed by the introduction of exhaust catalysts and sophisticated engine management systems. It is important to note that "oxygenated gasolines" have a hydrocarbon fraction that is not too different to traditional gasolines, but that the hydrocarbon fraction of "reformulated gasolines" ( which also contain oxygenates ) are significantly different to traditional gasolines. The last 10 years of various compositional changes to gasolines for environmental and health reasons have resulted in fuels that do not follow historical rules, and the regulations mapped out for the next decade also ensure the composition will remain in a state of flux. The reformulated gasoline specifications, especially the 1/Jan/1998 Complex model, will probably introduce major reductions in the distillation range, as well as changing the various limits on composition and emissions. I'm not going to list all 500+ HCs in gasolines, but the following are representative of the various classes typically present in a gasoline. The numbers after each chemical are:- Research Blending Octane : Motor Blending Octane : Boiling Point (C): Density (g/ml @ 15C) : Minimum Autoignition Temperature (C). It is important to realise that the Blending Octanes are derived from a 20% mix of the HC with a 60:40 iC8:nC7 ( 60 Octane Number ) base fuel, and the extrapolation of this 20% to 100%. These numbers result from API Project 45, and are readily available. As modern refinery streams have higher base octanes, these Blending Octanes are higher than those typically used in modern refineries. For example, modern Blending Octane ratings can be much lower ( toluene = 111RON and 94MON, 2-methyl-2-butene = 113RON and 81MON ), but detailed compilations are difficult to obtain. The technique for obtaining Blending Octanes is different from rating the pure fuel, which often requires adjustment of the test engine conditions outside the acceptable limits of the rating methods. Generally, the actual octanes of the pure fuel are similar for the alkanes, but are up to 30 octane numbers lower than the API Project 45 Blending Octanes for the aromatics and olefins [52]. A traditional composition I have dreamed up would be like the following, whereas newer oxygenated fuels reduce the aromatics and olefins, narrow the boiling range, and add oxygenates up to about 12-15% to provide the octane. The amount of aromatics in super unleaded fuels will vary greatly from country to country, depending on the configuration of the oil refineries and the use of oxygenates as octane enhancers. The US is reducing the levels of aromatics to 25% or lower for environmental and human health reasons. Some countries are increasing the level of aromatics to 50% or higher in super unleaded grades, usually to avoid refinery reconfiguration costs or the introduction of oxygenates as they phase out the toxic lead octane enhancers. An upper limit is usually placed on the amount of benzene permitted, as it is known human carcinogen. 15% n-paraffins RON MON BP d AIT n-butane 113 : 114 : -0.5: gas : 370 n-pentane 62 : 66 : 35 : 0.626 : 260 n-hexane 19 : 22 : 69 : 0.659 : 225 n-heptane (0:0 by definition) 0 : 0 : 98 : 0.684 : 225 n-octane -18 : -16 : 126 : 0.703 : 220 ( you would not want to have the following alkanes in gasoline, so you would never blend kerosine with gasoline ) n-decane -41 : -38 : 174 : 0.730 : 210 n-dodecane -88 : -90 : 216 : 0.750 : 204 n-tetradecane -90 : -99 : 253 : 0.763 : 200 30% iso-paraffins 2-methylpropane 122 : 120 : -12 : gas : 460 2-methylbutane 100 : 104 : 28 : 0.620 : 420 2-methylpentane 82 : 78 : 62 : 0.653 : 306 3-methylpentane 86 : 80 : 64 : 0.664 : - 2-methylhexane 40 : 42 : 90 : 0.679 : 3-methylhexane 56 : 57 : 91 : 0.687 : 2,2-dimethylpentane 89 : 93 : 79 : 0.674 : 2,2,3-trimethylbutane 112 : 112 : 81 : 0.690 : 420 2,2,4-trimethylpentane 100 : 100 : 98 : 0.692 : 415 ( 100:100 by definition ) 12% cycloparaffins cyclopentane 141 : 141 : 50 : 0.751 : 380 methylcyclopentane 107 : 99 : 72 : 0.749 : cyclohexane 110 : 97 : 81 : 0.779 : 245 methylcyclohexane 104 : 84 : 101 : 0.770 : 250 35% aromatics benzene 98 : 91 : 80 : 0.874 : 560 toluene 124 : 112 : 111 : 0.867 : 480 ethyl benzene 124 : 107 : 136 : 0.867 : 430 meta-xylene 162 : 124 : 138 : 0.868 : 463 para-xylene 155 : 126 : 138 : 0.866 : 530 ortho-xylene 126 : 102 : 144 : 0.870 : 530 3-ethyltoluene 162 : 138 : 158 : 0.865 : 1,3,5-trimethylbenzene 170 : 136 : 163 : 0.864 : 1,2,4-trimethylbenzene 148 : 124 : 168 : 0.889 : 8% olefins 2-pentene 154 : 138 : 37 : 0.649 : 2-methylbutene-2 176 : 140 : 36 : 0.662 : 2-methylpentene-2 159 : 148 : 67 : 0.690 : cyclopentene 171 : 126 : 44 : 0.774 : ( the following olefins are not present in significant amounts in gasoline, but have some of the highest blending octanes ) 1-methylcyclopentene 184 : 146 : 75 : 0.780 : 1,3 cyclopentadiene 218 : 149 : 42 : 0.805 : dicyclopentadiene 229 : 167 : 170 : 1.071 : Oxygenates Published octane values vary a lot because the rating conditions are significantly different to standard conditions, for example the API Project 45 numbers used above for the hydrocarbons, reported in 1957, gave MTBE blending RON as 148 and MON as 146, however that was partly based on the lead response, whereas today we use MTBE in place of lead. methanol 133 : 105 : 65 : 0.796 : 385 ethanol 129 : 102 : 78 : 0.794 : 365 iso propyl alcohol 118 : 98 : 82 : 0.790 : 399 methyl tertiary butyl ether 116 : 103 : 55 : 0.745 : ethyl tertiary butyl ether 118 : 102 : 72 : 0.745 : tertiary amyl methyl ether 111 : 98 : 86 : 0.776 :