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1994 fertilizers, mixed fertilizers fertilizers, mixed fertilizers V 0500 08 -311 Fertilizers of Higher Efficiency Based on Natural Zeolites. --(SOPKOVA, A.; BUBANEC, J.; CERNAJ, P.; SINGLIAR, M.; MONDIK, M.; BUDINSKA, V.; FABIAN, P.; Chem.

The authors have established conditions for the chromatographic separation of a mixture of glycol ethers. Optimum separation has been achieved on polyneopentylglycol succinate whose concentration in the column was gradually increasing from 2% at the column inlet to 10% at the end of column. The retention times and retention indices of the individual glycols and ethers have been determined, too. The dependence of the logarithm of net retention time on the number of ethoxy groups has been found linear also for the first members of the series. This fact can be utilized for the identification of unknown glycol ethers in hydraulic liquids .Glycol ethers belong to chemical products important for industry. They are prepared from ethylene oxide and the respective alcohol; the crude product is always a mixture of the ethers of mono-and poly glycols. Besides the ethers, the crude product also contains glycols resulting from the reaction of ethylene oxide with water present in the alcohol.The mixture of glycol ethers can be analysed by chromatographic methods, i.e. by paper chromatography subsequent to the preparation, from the ethers, of esters of 3,5-dinitrobenzoic acid!, or by gas chromatography. Ghanaem and Swann 2 analysed several glycol ethers and glycols on a mixed stationary phase, polyphenyl ether-Carbowax, on an inert support material, Fluoropak 80. Another mixed phase, i. e. silicone oil DC 703 + tetraethyleneglycol dimethylether has been employed by Kato and coworkers 3 for the separation of a similar mixture of compounds. The retention times of these compounds on silicone oil DC 550 have been measured by Nakagawa and coworkers 4 • Palfram and Walkers have recommended Porapak S for the quantitative analysis of glycols and glycol ethers a nd, on the latter phase, they also measured the retention times of several mono ethers of ethylene glycol and diethylene glycol. Other papers dealing with glycols and glycol ethers 6 ,7 do not mention the separation of glycol ethers .. The separation of ethylene glycols from glycol ethers on the above phases was relatively poor. On the mixed phases, ethylene glycol is eluted together with its ethyl ether. On the silicone oil alone, the ethylene glycol peak overlaps the peaks of ethylene glycol mono methyl and monoethyl ethers and the diethylene glycol peak overlaps the peaks of its mono methyl and monoethyl ethers. A complete separation of glycols Collection Czechoslov. Chern. Cornrnun. IVo!. 341 (/969)

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