Organic liquids acetonitrile

Sometimes electrochemists are forced to construct electrochemical cells without water, e.g. if the analyte is water sensitive or merely insoluble. In these cases, we construct the cell with an organic solvent, the usual choice being the liquids acetonitrile, propylene carbonate (I), N,/V-dirrielhylformamide (DMF) or di-methylsulphoxide (DMSO), each of which is quite polar because of its high dielectric constant e. 

Obtain samples of the following 11 organic liquids contained in individual small dropper bottles n-hexane (or other alkane), acetonitrile, methylene chloride, acetone, toluene, methanol, diethyl ether, ethyl acetate, ethylbenzene, ethanol, and chloroform. Then label each of the test tubes from step 1 with the names, or an abbreviation of the names, of these liquids. 

DDT Metabolism.-- The metabolism of DDT has been studied in R and S fish, following similar protocols to chlorinated cyclodiene metabolism organic extraction (acetonitrile), thin layer chromatography of organic extracts, and liquid scintillation counting of the resultant spots (4). When S and R fish were exposed to 60 yg/l of 14C-labelled , -DDT for 4 hr, radioactivity was found in the spots which co-chromatographed with... 

Non-aqueous (or-oil-in-oil) emulsions, where the phases are two immiscible organic liquids, have received relatively little attention in the literature. Riess et al. [116-119] have studied the stabilisation of waterless systems with block and graft copolymers, where one of the liquids is a good solvent for one of the blocks and a non-solvent for the other, and vice versa. Thus, poly(styrene-b-methylmethacrylate) copolymers could emulsify acetonitrile/cyclohexane mixtures, and poly(styrene-b-isoprene) was effective for DMF/hexane systems [116]. These, however, are not HIPE systems. 

Amide derivatives of trans- 1,2-diaminocyclohexane have proven to be particularly reliable gelators (Fig. 18). A simple alkylamide derived from this compound can gelate a wide range of organic liquids—from hexane to acetonitrile, ethyl acetate to silicone oil—in concentrations below ten grams per litre of liquid. In the case of hexane, one molecule of gelator interacts with... 

FeS2, etc. [i]. Polar organic liquids such as acetonitrile, y-butyrolactone, dimethylsulfoxide, 1,2-dimethoxyethane, dioxolane, propylene carbonate, and methyl formate are the most common solvents for electrolyte solutions in primary Li cells. Thionyl chloride (SOCI2 ) and sulfuryl chloride (SO2CI2) are inorganic compounds that serve as both the solvent and the active cathode material in primary Li batteries [i]. 

Alumina and titania in different solvents were studied in [822]. MgO and ZnO in seven organic liquids were studied in [1686]. Silica in a series of nonaqueous solvents and in acetonitrile-water and methanol-water mixtures was studied in [3139,3140]. Only positive potentials are reported, probably by mistake. Silica in decane was studied in [3141]. ZnO in absolute methanol, ethanol, and propanol was studied in [3142]. Montmorillonite in 2-propanol was studied in [3143]. Silicon in a 99% l-butanol-1% water mixture was studied in [3145]. In [3146], 11 solids (oxides and inorganic salts) in 9 solvents were studied. 

Nonaqueous two-phase systems employ two largely immiscible liquids. Examples include dissolving the Lewis base in acetonitrile, nitrobenzene, or 2,5-hexadione and the organometallic acid chloride in a nonpolar organic liquid such as hexane, decane, or carbon tetrachloride. 

The solvent is limited to organic liquids such as acetonitrile, propionecarbonate, etc. Water drastically decreases the performance of the cell. Water is considered to prohibit the bonding of the dye onto the Ti02-... 

Note 1. A direct extraction of theophylline from coffee is not practical. Direct solvent switch between the aqueous sample containing the analyte and the organic mobile phase is not possible because of the nonmiscibility of the liquids. Acetonitrile could substitute chloroform, but the stationary phase performances in terms of analyte reeovery will be badly compromised. 

Aluminum salts (e.g. nitrate) have proved to be a popular source for the synthesis of alumina particles through macroemulsions, as clearly shown from the above examples. However, there are other examples where aluminum alkoxides are used for the same purpose. In one example provided by Hardy etai [177], the procedure of emulsification involved ultrasonication of the alkoxide in immiscible, non-reacti ve, polar organic liquids prior to contact with water for direct conversion of the alkoxide droplets to solid particles. Thus, aluminum secondary butoxide dispersed in acetonitrile or propylene carbonate was hydrolyzed by addition of water [ 177] to obtain generally near-spherical particles of alumina varying in size from several microns to several nanometers. These particles, amorphous without calcination, changed to y-alumina of high surface area on calcination at 6(X) C and 0-alumina at IGOO C. 

To determine how to best extinguish a fire involving an organic liquid, it is best to consult a well-written Safety Data Sheet (SDS). Appendix A shows the SDS for acetonitrile, a common solvent with the formula, CHjCN. The pietogram in Part 2.2 quickly shows that it is flammable. Part 9.1 indicates acetonitrile is less dense than water and it is also eompletely soluble in water. This is an indication that water can probably be used to extinguish an acetonitrile fire, and Part 5.1 confirms that a water spray, alcohol-resistant foam, dry chemical or carbon dioxide can be used. 

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