Methanol/gasoline blends, effect

Elastomers. In the Investigation of the effects of methanol/ gasoline blends on elastomers [2] we established that the ultimate stress and the ultimate elongation In swelled elastomers are linearly related to the volume of rubber Vj. In the swelled network, I.e.,... 

Besides producing mixed-hydrocarbons (ultra-clean diesel), F-T process can also selectively produce mixed-alcohols (oxygenated fuel). The addition of mixed-alcohols into gasoline can effectively reduce HC and CO emissions. However, before directly used as fuels or blended with conventional fuels, the water content in the as-produced F-T mixed-alcohols must be reduced below 0.5wt.%. This dehydration step is essential but difficult since most of the contained alcohols form azeotropies with water. In our group, we studied the dehydration performance of microwave synthesized NaA zeolite membrane toward F-T produced mixed-alcohols [24, 25]. The membrane also showed excellent pervaporation performance toward dehydration of simulated F-T produced mixed-alcohols. The permeate consisted of only water and little methanol (< 10%) in aU the range of feed composition. This result confirmed that NaA zeolite membrane based pervaporation (or vapor permeation) process could be an effective technology for dehydration of F-T produced mixed-alcohols. 

Methanol, ethanol, and methy t-butyl ether (MTBE) are blended Into some commercial gasolines. It was Important to determine the effects of such blends on automotive elastomers especially those used In the fuel system. A summary of the results of our studies [1] and detailed data on the effects of methanol/gasollne mixtures on sixteen elastomers [2] have already been published. This paper presents detailed results of our Investigation of the effects of ethanol and MTBE mixtures with gasoline on mechanical and swell properties of automotive elastomers. Comparisons will be made with the effects of methanol/gasollne mixtures on elastomers. Experimental... 

Experience gained from the observation of oil seals in the automotive industry indicated that blends of methanol and gasoline can have a deleterious effect on many elastomers currently used in automotive oil seals. The effect of methanol as a constituent (15%) in an aromatic fuel is greater than that of other higher alcohols, e.g. ethanol, as is shown in Fig. 7. This should be compared with the swelling behaviour of the same range of elastomers in pure 42% aromatic fuel (Fig. 8). ... 

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