Method of detecting water-soluble vitamins in premixes
SUBSTANCE: invention relates to analytical chemistry. The method is realised as follows: a sample of ground up premix is filled with a hydrochloric acid solution and put into an opaque case which is put into an ultrasonic bath. Extraction is carried out for 15-20 minutes at 38-42°C and centrifuging is then carried out for 10 minutes at 8000 rpm. The mixture is then brought up to the mark in a measurement flask. The obtained solution undergoes chromatographic separation on a column with Purospher sorbent. Chromatography conditions: eluent A - 0.005 M lithium perchlorate solution, pH=2.5; eluent B- acetonitrile; elution gradient mode - from 0 to 26% eluent B for 14 minutes.
EFFECT: high efficiency and accuracy and possibility of detecting a wider range of vitamins independent of the premix base.
2 dwg, 5 tbl, 1 ex
The invention relates to analytical chemistry, namely the sections of extraction and chromatography. It can be used for chromatographic analysis in medicine and agriculture.
A known method for the determination of water-soluble vitamins (see GOST R 50929-96 "Methods for the determination of vitamins"). The essence of the method consists in the extraction of vitamins (B1, B2 and B5) of the sample solution of hydrochloric acid: a suspension of 1 g + 10 ml of hydrochloric acid concentration of 0.01 mol/l, the extraction is performed on the magnetic stirrer with heating for 10 minutes, centrifuged at 5000-6000 rpm for 3 minutes, bring in a volumetric flask of 25 ml to label with subsequent chromatographic analysis. The chromatography was carried out carried out in the following conditions: eluent (120 ml acetonitrile + 880 ml of water + 2.5 ml of triethylamine, 0.5 g octisalate sodium + orthophosphoric acid to pH of 7.6 on the pH meter), isocratic mode of elution, the rate of elution of 1.2 ml/min, the working wavelength spectrophotometric detector at 254 nm.
However, the known method to determine the mixture of only three vitamins - B1, B2 and B5, and the use of expensive ion-pair reagent articulate sodium reduces the resource column does not allow to work in gradient mode, in addition, this method is not applicable for premix mineral-based.
From the description of the data in the literature closest to the invention is a method proposed by Lanovoy L.A., Fedorova GA and GI Barama innovation center "Determination of water - and fat-soluble vitamins in multivitamin preparations by high performance liquid chromatography" AH, 2002, vol. 57, No. 1, 49-54, the extraction was carried out with a solution of lithium perchlorate in water (0.4 mol/l, pH of 2.4. Hitch 0.1-0.2 g + 20 ml of a mixture of perchlorate with 0.1% solution of butylacetamide (19:1 by volume), was stirred in the dark for 10 minutes at pH 5.5. If the pH value not established itself, brought hydroxide solution lithium, then brought the pH to 2.4 and were extracted for another 10 minutes. Added volumes were taken into account when calculating the concentrations. The chromatography was carried out was performed under the following conditions: eluent A - 0.4 M lithium perchlorate (LiClO4pH 2,4); eluent B - acetonitrile; gradient - 8 min 2% B, 17 minutes linear gradient from 5% to 18% B; flow rate 0.1 ml/min; temperature 35°C; the volume of the sample 4-10 ál. Registration started at 6 wavelengths(210, 220, 250, 260, 280, 300 nm). The duration of the pickup 25 minutes.
However, the proposed method is long and complicated technology, not applicable for premix mineral-based.
With the development of large-scale production and active introduction of multivitamin preparations both in agriculture and in medicine and food industry tightened control of their quality not only from the manufacturer, but also by p is the consumer. Consequently, it is important the analysis of a wider range of vitamins.
The objective of the invention is to improve the efficiency and accuracy of the method, identifying a broader range of vitamins, regardless of the basis of the premix.
The problem is solved as follows: the sample is pre-crushed premix is poured a solution of 0.01 N. hydrochloric acid, placed in a light-tight casing, which is mounted on the ultrasonic bath. The ratio of the sample and extractant picked so that the concentration of vitamins fall into the range of linearity of the developed chromatographic methods. Extraction spend 15-20 minutes at a temperature of 38-42°C. and Then centrifuged for 10 minutes at 8000 rpm, bring up to the mark in a volumetric flask. The resulting solution was used for chromatographic analysis. Chromatographic separation carried out on a column (250×4 mm with a sorbent Purospher RP-18e (5 µm). Chromatograph conditions were as follows: eluent A - 0.005 M solution of lithium perchlorate pH of 2.5; eluent B - acetonitrile; gradient elution mode from 0 to 26% of eluent B over 14 minutes. The injected volume of 40 ál. The wavelength of detection: UV detector from 0 to 8 minutes 250 nm, 8 to 10 minutes 200 nm, 10 to 12 minutes 230 nm, from 12 to 18 minutes 200 nm; fluorescence detector when the absorption at 270 nm from 0 to 12 minutes at 400 nm (luminescence), from 12 to 18 minutes to 495 nm (luminescence is).
Distinctive features of the proposed method are extracted using ultrasound for 15 to 20 minutes at a temperature of 38-42°C, centrifuged for 10 minutes at 8000 rpm, as the eluent used solution of lithium perchlorate concentration of 0.005 M, gradient elution from 0% to 26% acetonitrile in 14 minutes.
Extraction with ultrasound for 15 to 20 minutes at a temperature of 38-42°C allows to achieve a given completeness of extraction of vitamins premixes on any basis.
Centrifugation at 8000 rpm for 10 minutes allows you to achieve a more complete separation of the phases.
The proposed variant of the gradient allows to reduce the time of pickup from 25 to 18 minutes, while maintaining the quality of separation. It is established that lithium perchlorate concentration of 0.005 M, used only as a mobile phase, has a sufficient ion-pair effect on vitamins (improving the shape of the chromatographic peak), allows to achieve a given degree of separation (the separation criterion in all cases is greater than 1) and slightly pollutes the column.
The proposed method for the determination of water-soluble vitamins allows you to expand the Arsenal of up to 9 vitamins regardless of the basis of the premix is reliable and simpler technology.
The determination of vitamins is as follows: the sample previously is smallchange premix is poured a solution of 0.01 N. hydrochloric acid (ratio of sample and extractant picked so that the concentration of vitamins fall into the range of linearity of the calibration curve), the studied material is placed in a light-tight casing, which is mounted on the ultrasonic bath. Extraction spend 15-20 minutes at a temperature of 38-42°C. and Then centrifuged for 10 minutes at 8000 rpm, bring up to the mark in a volumetric flask. The resulting solution was used for chromatographic analysis. Chromatographic separation carried out on a column (250×4 mm with a sorbent Purospher RP-18e (5 µm). Chromatograph conditions were as follows: eluent A - 0.005 M solution of lithium perchlorate pH of 2.5; eluent B - acetonitrile; gradient elution mode from 0 to 26% of eluent B over 14 minutes. The injected volume of 40 ál. The wavelength of detection: UV detector from 0 to 8 minutes 250 nm, 8 to 10 minutes 200 nm, 10 to 12 minutes 230 nm, from 12 to 18 minutes 200 nm; fluorescence detector when the absorption at 270 nm from 0 to 12 minutes at 400 nm (luminescence), from 12 to 18 minutes to 495 nm (luminescence).
Compared the impact of different extraction methods on the degree of extraction of vitamins (for example vitamin B2)
|Methods of determination of water-soluble vitamins||Time extrage the Finance, min||Methods of extraction||The output of vitamin B2 %|
|GOST||10||Magnetic stirrer||at 88.1|
|The method according to Lanovoy et al.||20||Stirring in the dark||86,6|
|The proposed method||15-20||In the dark, the ultrasound frequency 35 kHz||96,4|
From table 1 it is seen that the highest yield of vitamin (96,4%) is achieved using ultrasound, for 15-20 minutes, similar results were obtained for other vitamins. Mechanical mixing and applying a magnetic stirrer to achieve given the completeness of extraction.
Compared the effect of temperature regimes on the degree of extraction of vitamins (for example vitamin B2)
|Methods of determination of water-soluble vitamins||Temperature||The output of vitamin B2 %|
|The method according to Lanovoy et al.||room||81,4|
|The proposed method||38-42°C||97,2|
Table 2 shows that when the temperature rises to 40°C, the yield of the vitamin is increased to 97.2 per cent, and lower temperatures make it difficult to achieve given the completeness of extraction, at a temperature above 42°C is destroyed unstable vitamins (B1, K3), similar results were obtained for other vitamins, so the temperature of 38-42°C is optimal for the conservation and more complete extraction of vitamins premixes.
Separation of the precipitate and the supernatant liquid is carried out by centrifugation. It was found that the mode proposed in the Guest: 5000-6000 rpm for 3 minutes, it is not possible to achieve complete separation of the phases, the proposed regime 8000 rpm for 10 minutes is optimal, as it achieves a more complete separation of the phases.
On the model solutions were experimentally selected conditions chromatographic separation of vitamins concentration of lithium perchlorate (0,4, 0,1, 0,05, 0.005 M) and gradient elution in such a way that one analytical procedure sample possible is Astelit the following vitamins: C, B1, B2, B3, B5, B6, H, B12, K3 - criteria for the separation of two adjacent peaks in all cases is greater than 1. Some characteristics of the chromatographic separation of the vitamins listed in table 3.
|The characteristics of the chromatographic separation of vitamins|
|Vitamin||Retention time, min (n=5, P=0,95)||Wavelength detection, nm||The criterion of separation|
|with fluorescence detection, while the absorption at 270 nm|
From table 3 and the chromatogram in figure 1 shows that the concentration of lithium perchlorate 0.005 M and a gradient from 0% to 26% of acetonitrile are optimal for a wide range of vitamins (9).
In the selected conditions set the range of linear dependence of the analytical signal of chromatographic peak area - concentration of vitamins in the solution. For vitamin B1 it was 0.5-20 µg/ml, for B5 - 0.5 to 100 μg/ml for the other vitamins and 0.5-50 µg/ml
On the model solutions evaluated the correctness and precision of the determination of vitamins in the mixture according to the developed methodology. Calculation of concentrations led by calibration curve. The ratio of the concentration of vitamins in the model solution was near what about their ratio premix formulations. The results are presented in table 4.
|Vitamin||Entered, ug/ml||Found, ág/ml||δ, %||W %|
From table 4 it is seen that the proposed technique improves the efficiency and accuracy of vitamins, because the relative error of quantification (δ) of not more than 5% (modulo), the coefficient of variation is not more than 4%. The developed method has been applied to the analysis of premixes. Chromatogram 1% premix, based on the zeolite is shown in figure 2.
|The results of the analysis of premix mineral-based (n=3, P=0,95)|
|Vitamin||Specified in the recipe, ug/g||Found, µg/g||W %||Δ, %*|
|* the discrepancy between the published data and results.|
From figure 2 and table 5 shows that the proposed method of determination of water-soluble vitamins allows you to expand the range defined vitamins from premixes on any basis, while the coefficient of variation less than 3%, the discrepancy between the published data and the results obtained not more than 9% (maximum difference of 15% according to GOST R 50929-96 "Premixes. Methods for determination of vitamins").
Thus, the proposed method of determination of water-soluble vitamins premixes improves accuracy and allows to expand the range defined vitamins to nine.
The method of determination of water-soluble vitamins premixes, including grinding, the capture of sample, extraction with hydrochloric acid, zentrifugenbau is s, the premise of the obtained solution in the volumetric flask, the chromatography was carried out in reversed-phase variant using gradient elution mode, as eluents used solution of lithium perchlorate and acetonitrile, characterized in that the extraction is carried out with ultrasound for 15 to 20 minutes at a temperature of 38-42°C, centrifuged 10 min at 8000 rpm, a solution of lithium perchlorate is used in a concentration of 0.005 M, gradient elution from 0% to 26% acetonitrile for 14 minutes
SUBSTANCE: four identical suspensions of test microorganisms are produced to estimate activity of an antimicrobial preparation. The first one contains physiologic saline, the second one - the antimicrobial preparation in the preset concentration Cprep, the third one - physiologic saline, and the fourth one - the antimicrobial preparation in the same amount. After a certain period of time td, a detergent is added to the third and fourth suspensions, while two first samples of suspension are filled with physiologic saline so that microorganism concentration are the same in all four samples of suspension. The fluorescence levels of these suspensions are measured with a laser and/or non-laser fluorometre at the moment t1 and after an interval Δt equal to 15 minutes approximately. Then measurements are performed once again at the moment t2 and after an interval Δt. Further, the measured values are used to calculate the antimicrobial preparation efficacy ε by solving kinetic equations.
EFFECT: use of the method allows cutting time of estimated efficien of the antimicrobial preparation, more precise and simplified procedure of choosing a preferential antimicrobial preparation.
2 cl, 1 tbl, 1 ex
SUBSTANCE: acid hydrolysis of 0.3 g of laminarid or laminarid granules with 15 ml of 10% sulfuric acid, volume of hydrolysate is brought to 50 ml. Volume of aliquot part of solution 10 ml is taken and neutralised first with sodium hydroxide to pH 9.7, then with solution of sulfuric acid to pH 3.5, after that with solution of sodium hydroxide to pH 8.9, pH of solutions is controlled in potentiometrically. Filtration is carried out, volume of filtrate is brought to 25 ml with water, 1 ml of obtained solution is treated with 0.2 ml of 1% of picric acid solution in presence of 3 ml of 20% of sodium carbonate solution with heating. Volume of solution is brought to 25 ml and optic density is measured at water background spectrophotometrically at wavelength 356 nm with simultaneous measurement in the same conditions of optic density of 0.2 ml of 1% of picric acid solution and of glucose solution. Content of reducing sugars (C,%) is calculated by formula: where a1 is portion of glucose, in g; a2 is portion of polysaccharide preparation, in g; D1 is optic density of picric acid solution; D2 is optic density of glucose solution; D3 is optic density of tested solution; W is loss of glucose in mass during drying, in %; 5000 is coefficient which takes into account dilutions of solutions in analysis.
EFFECT: invention allows to increase accuracy and reproducibility of results.
2 ex, 4 tbl, 3 dwg
SUBSTANCE: to realise method of determining biocompatibility of organism with foreign material, before its introduction into organism sampling of analysed material from individual is carried out, foreign material in form of powder with particle size from 0.5 to 1 mm3 in amount 500 mcg is added directly into cell substance and cytochemical parametres of fermentative activity of cells before and after introduction of foreign material into cell substance are determined. Fermentative activity of cells is determined by not less than 5 parametres, after three time intervals, by determining optic density of cell substance, obtained values being expressed in form of stimulation index, after which calculated is mean value of stimulation index of each separate cytochemical parametre of cell substance reaction to each foreign material. After that said parametres separately on each foreign material are summed up, using only integer part of stimulation index number, scale of biocompatibility is built and used to make conclusion about degree of compatibility of each separate foreign material and particular organism. The less is total index of stimulation, the more foreign material is biocompatible with organism.
EFFECT: improvement of method.
5 cl, 17 tbl, 3 ex
SUBSTANCE: cell material containing marrow stem cells in a liquid culture medium is placed over a prepared agar medium containing marrow cells producing homing factors. After incubation of the prepared two-layer culture, inadherent cells are transferred to a semi-viscous culture medium and incubated in a mode required for colony-formation. Then by recording the difference of stem cell count in the cell material in the reference, and after placing on the agar medium containing homing factors, stem cells migrated by stem cell homing factor are counted.
EFFECT: invention allows simplifying the method for determination of production of stem cell homing factors due to the use of the agar medium as a semipermeable membrane and the introduction of colony-forming ability change of the cell material as an evaluation criterion of production of stem cell homing factors.
1 tbl, 1 ex
SUBSTANCE: solutions of a substance to be determined and a reference sample are prepared. 0.1 M sodium hydroxide is used as a solvent for preparing the analysed solutions. Potassium chromate or potassium ferricyanide is used as a reference sample. The optical density of the solution of the analysed substance and the reference sample of potassium chromate or potassium ferricyanide is measured by a spectrophotometre at wave length 264 or 298 nm respectively. The results are calculated by formula with an introduced conversion factor.
EFFECT: higher reproducibility of results of determination and reduced analytical error.
SUBSTANCE: preparation is injected in a visual organ of a wakeful piglet. Before, eyelids are opened and hold open to choose an injection point in the visual organ; tissue damage is estimated by their temperature; drug temperature before injection is measured with using a thermal imaging unit; measurement is started before drug injection; drug temperature before injection is set equal to specified point temperature; the drug is injected once in the conjunctival cavity in a minimum single dose; then eyelids are released and separated again every second minute for duplicate temperature measurement; if observing hyperthermia in development for the first minutes after drug injection, the conjunctival cavity is rinsed with 0.9% normal saline with instilling a drop of 1% lidocaine hydrochloride and making a conclusion of high local toxicity and potential damage of the conjunctival epithelium.
EFFECT: invention allows improving safety, accuracy and rate of estimating local drug toxicity.
SUBSTANCE: at first, total potassium asparaginate and magnesium asparaginate is determined by a spectrophotometric method when measuring optical density of a coloured reaction product of asparaginate-ions and ninhydrin at wave length 568 nm; amount of magnesium asparaginate is determined by chelatometry titration. To calculate amount of potassium asparaginate in preparation Asparcam, the content of magnesium asparaginate is subtracted.
EFFECT: method provides exact results; it is sensitive, easy-to-implement, and profit-proved; it does not require toxic reagents.
2 ex, 6 tbl
SUBSTANCE: invention refers to a method for HPLC-based determination of verapamil enantiomers in active pharmaceutical ingredients, tablets and blood plasma samples.
EFFECT: extended range of HPLC techniques for determination of verapamil enantiomers, simplified method as compared with common procedures, available reproduction and reduced research costs ensured by the optimal choice of the equipment and chemical agents.
1 cl, 6 dwg, 4 tbl
SUBSTANCE: in the method, a biological object is infused with ethylacetate twice for 30 minutes each time. Ethylacetate extractions are separated, combined and dehydrated. The combined extraction is first evaporated in an air current to a small volume and then in a nitrogen current until complete evaporation of the solvent. The residue is dissolved in a system of solvents, undergoes chromatography in a macro-column with sorbent using a multicomponent mobile phase. Eluate fractions containing 2-methoxy-4-allylhydroxybenzene are combined and evaporated. Before chromatography, the residue is dissolved in hexane, extracted, separated, acidified, saturated with sodium sulphate and extracted with diethyl ether. The ether extraction is separated, dehydrated, evaporated until complete removal of solvent. The residue is dissolved in a mixture of solvents - hexane - dioxane - proanol-2 (40:5:1). Determination is carried out through chromatography-mass spectrometry using a capillary macro-column. The amount of 2-methoxy-4-allylhydroxybenzene is determined from the area of the chromatographic peak.
EFFECT: increased sensitivity of determination.
3 tbl, 2 ex
SUBSTANCE: method of pyrazinamide determining is based on the fact that 0.1 M solution of sodium hydroxide or 0.1 M solution of hydrochloric acid are used as a solvent for preparation test solutions. Potassium chromate or benzoic acid is used as a standard for comparison. Optical density of determined substance solution and the standard for comparison of potassium chromate or benzoic acid at a spectrophotometre at a wavelength of 268 nm are measured. The calculation of the results is carried out by the formula using the conversion factor.
EFFECT: reduction of analysis error, standardisation of analysis techniques.
SUBSTANCE: method for chromatographic analysis of a substance involves exposing the separated mixture of substances carried by a carrier through a chromatographic column to acoustic oscillations. Before chromatographic analysis, a liquid nematic crystal is deposited on the wall of the chromatographic column, where the said crystal is directed across the propagation of sound oscillations.
EFFECT: high efficiency of separating an analysed mixture of substances into components using sound waves.
FIELD: oil and gas industry.
SUBSTANCE: gas chromatograph includes chamber for samples with piston position sensor, which is connected through sample valve to pipeline and through oil pump to reservoir for compensation of hydraulic oil pressure, electrical thermostat with temperature sensor and chromatograph tube located inside thermostat, which is in-series connected on one side through rotating sample injector, zeolite filter, the first return valve and isolating valve of chromatograph with connection line of sample valve and chamber for specimens, in-series connected on the other side to the second return valve, fraction detector, bottle with sample portion and the second pressure sensor. At that, rotating sample injector is in-series connected to pressure reducer, valve for transporting medium, bottle with compressed nitrogen and the first pressure sensor, bypass line with bypass valve is parallel connected to rotating sample injector, chromatograph tube and fraction detector, and circuit of electronic telemetry is connected to output of fraction detector. Method of downhole gas chromatography is proposed as well.
EFFECT: development of device allowing to perform gas chromatography for determining the type of well fluids in well in real time.
3 cl, 5 dwg
SUBSTANCE: device for chromatographic separation of substances contains three chromatographic columns connected to each other by crossover channels fitted with switching elements and extra channels fitted with switching elements which are connected to a source of the separated medium, eluent stream and system of receivers for collecting fractions. A controlled flow divider, one or more detectors and an analytical column are fitted at the output of the chromatographic separation system. Also in order to increase output and efficiency of the device for chromatographic separation of substances dissolved in supercritical fluids, the receivers for collecting fractions are fitted with level sensors and their outputs are further fitted with pilot-controlled valves which prevent diffusion of collected substances between receivers. The device also has a collector with a receiver and a flow regulator for the stream of fluids evaporated when pressure falls below the critical value. The device also has a high-pressure pump whose output is also connected to the flow regulator with pressure sensors at the input and output and a flow sensor, which guide part of the stream of formed fluids through the pilot-controlled valve into one or more spherical reactors which have an outer insulating layer and outer and inner heat chambers connected to heat or cold sources, temperature sensors, and the other part of the stream is directed to the analytical column and reactor. The reactor is connected through the pilot-controlled valve to the spherical collector of fluid solutions which is similar to the reactor whose output is connected to liquid batch collection device.
EFFECT: more accurate batching and increased output and efficiency of the disclosed device.
SUBSTANCE: method involves taking a sample, concentration of impurities, chromatographic analysis with separation of the concentrate on a capillary column and mass-selective detection while raising temperature from 35°C to 280°C, isolation of tridecane and 1-methylnaphthalene as reference compounds on the chromatogram, calculation of their concentration ratio in the sample and calculation of the time of contact between diesel fuel and water using the formula: x=0.42·y-1.8, where x is the time of contact between diesel fuel and water, h; y=Stridecane/Smethylnaphthalene; Stridecane and Smethylnaphthalene are area of peaks of tridecane and 1-methylnaphthalene on reconstructed chromatograms on selective ions with mass to charge ratio of 85 for tridecane and 145 for 1-methylnaphthalene, which correspond to concentrations of given compounds in the sample.
EFFECT: simple and reliable method with high information content.
1 ex, 1 tbl
FIELD: test equipment.
SUBSTANCE: proposed invention relates to gas chromatographic analysis and can be used in alcohol quality tests. Proposed method consists in that, additionally, water-spirit mix in the ratio of 60/40% by volume is prepared to a series of model samples based thereon to prepared by adding every component of analysed drink separately in said mix. Then model sample are analysed at the inlet assembly temperature of 180°C, 250°C and 310°C. Note that unknown substance detected in model sample is qualified as artifact formed in analysis, while is it is absent from model samples, check sample is prepared by combining the entire series of model samples to be analysed at aforesaid 180°C, 250°C and 310°C. Then mass spectra and chromatograms related therewith are analyzed and, if there is no revealed unknown substance in check sample, it is qualified as marker of nonfoods origin.
EFFECT: unambiguous identification of chemical compounds and fragments thereof as well as their origin, higher accuracy and faster identification.
4 tbl, 3 ex
SUBSTANCE: invention relates to chemistry and can be used in coke-chemical production when processing coke gas. The method involves using fractions of heavy crude pyridine bases which form during coal carbonisation as raw material, from which pyridine bases are extracted first and the obtained faction of crude quinoline bases is split into components. The fractions of crude quinoline bases are split into components through supercritical preparative chromatography, where the separated mixture is brought into contact with gas in supercritical state, which is simultaneously the mobile phase and adsorbent.
EFFECT: simpler, faster and more reliable separation.
SUBSTANCE: invention relates to a novel chemical compound - 4-(2-hydroxyethyloxy)-4'-cyanoazoxybenzene which can be used as a liquid crystal stationary phase for gas chromatography.
EFFECT: given compound has higher structural selectivity than structural isomers of lutidine.
1 ex, 1 tbl
SUBSTANCE: sample analysis device has a column for anion-exchange chromatography, as well as a buffer for elution, which contains an ion formed from a group consisting of a nitrate and a chloride. The device also includes an amperometric sensor and a spectroscopic sensor. The two sensors are placed such that, an eluate is obtained from the column.
EFFECT: provision for additional and improved methods of and systems for determining characteristics of saccharides using anion-exchange chromatography.
14 cl, 21 dwg
SUBSTANCE: method of determining content of diesel fuel in lubricating oil of an internal combustion engine involves the following stages: preparing a mixture which contains an oil sample and C5 hydrocarbon, such as C5 alkane; injecting the mixture into the injector (11) of gas chromatograph (10); obtaining chromatographs of the sample; determination of the firs parametre M, which characterises peak area related to C5 hydrocarbon, such as C5 alkane, determination the second parametre C, which characterises area of at least one peak, related to a hydrocarbon, which characterises diesel fuel; and determination of content T of diesel fuel using formula (I): where a and b are constants, which define equation y=ax+b of a calibrating straight line of the ratio of the second to the first parametres as a function of content of diesel fuel.
EFFECT: increased accuracy and reliability of analysis.
8 cl, 3 dwg
FIELD: process engineering.
SUBSTANCE: invention relates to process engineering and can be used in deeper conversion of hydrocarbons, their cracking and reforming. Proposed device comprises three chromatographic columns, one for sorbent layer regeneration from the mix heavy fraction and the other two for mix separation and release of light fraction. Aforesaid columns are divided into sections, each filled with sorbent that moves forced by carrier gas. The latter is fed from the first section and withdrawn from the third section, via transition channels incorporating controlled switching elements. Each column communicates with the system of preparation of introduction of the mix to be separated and with fraction collectors. There is a sorption-desorption activator arranged in sample preparation and introduction line to destruct complex organic molecules and distill separated substance.
EFFECT: higher efficiency.
FIELD: process engineering.
SUBSTANCE: invention relates to chromatographic fractionation of substances and can be used in biotechnologies, pharmacology, food industry, in purification of industrial wastes and drinking water. Proposed column comprises casing, outer porous partition, sorption layer and inner porous partition made up of closed similar curved surfaces that embrace each other successively. There are also a gap between said casing and said outer porous partition for distributed intake of substances to be separated, inlet and outlet channels. Ultrasound radiator is mounted at the column center, at preset distance from sorption layer. Ultrasound radiator shape is similar to curved surfaces of aforesaid column components. Said ultrasound radiator can be adjusted in frequency and intensity of radiation.
EFFECT: reduced time of sorption-desorption separation, higher efficiency.