METHOD OF DEPRESSANT DETECTION ON BASIS OF ETHYLENE COPOLYMER WITH VINYL ACETATE APPLIED FOR DIESEL FUEL Russian patent published in 2008 - IPC G01N33/22 G01N31/22 G01N21/78 

FIELD: chemistry.

SUBSTANCE: method includes diesel fuel sampling, composition mixing and following heating and cooling to temperature 18...20°C, composition mixing, sedimentation, composition phasing and depressant detection based on colouring change. After catalyst is added, reaction of ether groups saponification (hydrolysis) is performed. Ethylene copolymer and vinyl acetate molecules contain these ether groups at heating and holding of composition on boiling water bath with backflow condenser not less then 15 minutes. After cooling and mixing 2...3 ml of composition is sampled, added with indicator, mixed, phased and detected for depressant based on reddish-brown colouring of water-alcohol phase and blue iris on the brder of organic and water-alcohol phase. As catalyst 0.5 n water-alcohol solution KOH is used in relation to fuel sample 1.0:2.5, and as indicator 0.2 n iodine alcoholic solution is used in relation to fuel sample 0.25:1.0.

EFFECT: improved reliability and reduction in price of method.

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