Ethanol systems, compatibility

Compatibility of ethanol with tank and piping materials such as carbon steel, stainless steel, and Fiberglas is good. Zinc linings and epoxy linings are not stable in ethanol systems and are not recommended for use. Also, epoxy adhesives and resins are dissolved by ethanol. Teflon and nylon are compatible elastomers. In... 

Solubility/miscibility Miscible with MEK, ethanol, acetone Biological considerations No limitations except high volumes via the IV route can disturb systemic electrolyte balance and cause hemolysis and hematuria Chemical compatibility/Stability considerations None Uses (routes) All. The vehicle and solvent of first choice... 

The features of the monoHthic integrated sensor systems have not yet been fully exploited. The almost linear relationship between input reference voltage and microhotplate temperature renders the systems suitable for applying any temperature modulation protocol. Due their compatibility with other CMOS-based chemical sensors the microhotplates can be also combined with, e.g., polymer-based mass sensitive, calorimetric or capacitive sensors. The co-integration with such sensors can help to alleviate problems resulting from cross-sensitivities of tin-oxide based sensors to, e.g., volatile compounds such as hydrocarbons. A well-known problem is the crosssensitivity of tin oxide to humidity or ethanol. The co-integration of a capacitive sensor, which does not show any sensitivity to CO, could help to independently assess humidity changes. 

The solvent system used here consisted of cyclohexane and 5% ethanol. This mobile phase will dissolve many petroleum fractions, produce a stable base line, and is compatible under ambient laboratory conditions with many common liquid chromatographic detectors. The system was operated at 10 C above the critical temperature of cyclohexane (280°C). 

Very fine filters are recommended for ethanol dispensers to ensure that waterborne solids do not contaminate vehicle filters or fuel injectors. Dispensing hoses delivering ethanol and other alcohol fuels to vehicles may be green or blue in color to signify their compatibility with alcohol fuels. Also, blending ethanol with conventional fuels helps to minimize compatibility problems with existing fuel system components. 

Ethanol is widely acknowledged to be less aggressive toward metals and elastomers than methanol, but little research and development has been devoted to the specific problems posed by ethanol. Ethanol typically has more water in it than methanol (an artifact of production) which may affect solubility of contaminants and corrosion potential. One ethanol contaminant that can arise from production is acetic acid, which is water-soluble and will corrode some automotive fuel system components. For instance, General Motors found that E85 caused more corrosion in fuel pumps than M85, presumably because of a higher level of dissolved contaminants [3.2]. Since much more development has been devoted to compatibility with methanol fuels, the general approach for ethanol has been to use materials developed for methanol, even though they may be over-engineered. ... 

The metals recommended for use with ethanol include carbon steel, stainless steel, and bronze [3.10]. Like methanol, metals such as magnesium, zinc castings, brass, and copper are not recommended. Aluminum can be used if the ethanol is very pure, otherwise it should be nickel-plated or suitably protected from corrosion by another means. The metals compatible with ethanol represent a much wider range than those for methanol and represent most of the metals currently used in fuel systems, so few changes would be anticipated when using ethanol. 

The fuel lines onboard flexible fuel vehicles using ethanol will typically be designed to accommodate methanol fuels and should be more than adequate for ethanol. Most fuel system components designed for gasoline are likely also to be compatible with ethanol. In a test of a 1994 model fuel injected vehicle, only slight stiffening of the fuel line was observed [3.11]. No other materials compatibility problems were observed in the fuel system. 

In designing an efficient SSF system for the conversion of cellulose to ethanol, the fermentation temperature should be compatible with the saccharification temperature that is generally between 45 and 55 °C. The optimal temperature for the most commonly available cellulase is about 50 °C. Therefore, the use of high-temperature-tolerant microbes is desirable for the application of the SSF process to ethanol production. Typical industrial ethanol-producing yeast strains are mesophiHc with an optimal fermentation temperature of 30-37°C. Only a few yeast strains that are thermotolerant, as well as good ethanol fermenters, have been described. However, some thermophilic bacterial species are known to produce ethanol from cellulosic-derived carbohydrates [68,69]. 

The flame-based detector was reported to accept in excess of 20 ui/mln of 10-25Z aqueous methanol without extinction of the flame Optimum response was obtained at flow rates below 5 iii/min. Compatible solvent systems were aqueous methanol (up to 50%), acetone and ethanol (up to 40%) The minimum detectable quantity (at 5 times noise) measured for the FPD was 2 pg P. The dual-flame TSD can also be directly Interfaced with mlcrocaplllary packed columns The TSD was reported to be compatible with 75 to 100% aqueous methanol The utilization of microbore column LC-TSD for the analyls of nitrogen, phosphorous, and halogen containing compounds is particularly Important in studies of biomolecules, and drugs and their metabolites in physiological fluids ... 

The addition of cosolvents to ionic liquids can result in dramatic reductions in the viscosity without changing the cations or anions in the system. The haloalu-minate ionic liquids present a challenge due to the reactivity of the ionic liquid. Nonetheless, several compatible co-solvents have been investigated, including benzene, dichloromethane, and acetonitrile [13-17]. The addition of as little as 5 wt.% acetonitrile or 15 wt.% of benzene or methylene chloride was able to reduce the absolute viscosity by 50% for [EMIMjCl-AlCls ionic liquids with less than 50 mol% AICI3 [13]. Non-haloaluminate ionic liquids have also been studied with a range of co-solvents including water, acetone, ethanol, methanol, butanone, ethyl acetate, toluene, and acetonitrile [6,18-22]. The ionic liquid response is similar to that observed in the haloaluminate ionic liquids. The addition of as little as 20 mol% co-solvent reduced the viscosity of a [BMIM][BF4] melt by 50% [6]. 

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