HU217029B - Method for indicating and measuring concentration of organic compounds preferably of hydrocarbons, reagent and apparat for thereof - Google Patents

Abstract

The present invention relates to a method for cooling and quantifying organic compounds, especially hydrocarbons. The present invention relates to organic compounds in an open or cyclic 1 to 10 carbon atoms perchlor or perchlor, or perchlorofluorescent hydrocarbons, and to a mixture of anhydrous compound or a strong acid anhydride, followed by the addition of manganese heptoxide in an alkaline lubricant. heat and, based on the shrinkage of the lead, the presence of organic compounds is calculated or the amount of organic compounds in the sample is calculated by manganese heptoxide measurement on the oxidation of organic compounds. The invention also relates to a liming reagent, characterized by a thermally open or cyclic, saturated carbon perchloride or perchlorate of 1 to 10 carbon atoms, or to a manganese heptoxide of 0.02 to 200 g / l of fully halogenated gluten. The invention also relates to a grinder for defining the invention, which is a reaction vessel (2) inserted into a Dewar bottle and is sealed with a glass jar (4) provided with a thermally dispensing opening (5) and buried in the reaction vessel (2) in the abrasive glass stubble (4). has a thermal sensor (7) provided with an outlet cable (6). ŕ

Description

The present invention relates to a reagent suitable for the detection and quantification of organic compounds, in particular hydrocarbons such as oil, gasoline and the like, and to a patent for the detection and measurement method and apparatus therefor.

The chemical inactivity of hydrocarbons, especially paraffinic compounds, makes it difficult to find a suitable method for their detection and quantification. The known methods are not simple enough and can only be used in laboratory conditions as they are not carried out at room temperature at a practical rate. In technical life, this task is solved by instruments, physical or physico-chemical methods. These include UV and IR spectrophotometry, gas chromatography. These include the HORIBA portable instrument for detecting groundwater hydrocarbon contamination or the solid adsorbent glass tube for DRAGER kw hydrocarbons for air analysis. Known instruments are expensive, have a narrow scope and require a power source. Gravimetry is one of the traditional analytical methods, but it is not suitable for volatile substances and is not suitable for field applications. Within the framework of environmental protection, it is increasingly important to detect and define the hydrocarbon contamination of soil and groundwater, and to determine the extent of such contamination. This task requires easy and fast field-based methods and tools that do not require network power and lab background, and allows relatively low cost testing without the need for expensive expensive instruments. The prior art does not provide a satisfactory solution to these problems.

It is an object of the present invention to provide a method according to the foregoing requirements.

The present invention is based on the discovery that Mn (VII) -containing manganese heptoxide quantitatively oxidizes secondary and tertiary carbon atoms in hydrocarbons and in carbon chains in general, and this reaction occurs instantaneously at room temperature in dilute solutions. However, due to the instability and water sensitivity of Mn ₂ O ₇ , the reaction cannot be used under normal conditions, however, it has been found that Mn ₂ O _{7 is} stable in a fully halogenated organic solvent such as carbon tetrachloride and is safely oxidized in the presence of executable. Hereinafter, the term "solvent" always refers to the above halogenated hydrocarbon.

It is a further realization of the present invention that the manganese-heptoxidation oxidation in the solvent can be used as a qualitative method, as well as titrimetric, photometric and colorimetric quantitative methods, similar to conventional chemical analytical methods. In the solvent medium Mn (VII) it exerts its oxidative effect by reducing it to Mn (II) under "acidic" and to Mn (IV) under "neutral". Thus, the hydrocarbons in the solvent can be titrated classically with a solvent solution of Mn ₂ O ₇ and the color of the first drop of excess manganese heptoxide indicates the end point. The "acidic" effect of the reaction (since this is to be understood as the concentration of the electrophilic component instead of the (H ⁺ ) concentration) is the presence of C1 ₂ O ₇ , which is anhydride of perchloric acid and is soluble in the solvent used.

The widespread application of the invention is provided by the discovery that oxidation of Mn ₂ O ₇ can be used in a "neutral" reaction by the continuous removal of dark Mn (IV) formed by the addition of potassium persulfate (K ₂ S ₂ O ₈ ). from the solvent phase, thus allowing the indication of the endpoint of the indication.

If an excess of manganese heptoxide is added to the hydrocarbons to be determined but in known amounts, after oxidation an equivalent amount of manganese hepoxide consumed for oxidation can be indirectly determined, e.g. dipyril sulfate by colorimetry or photometric reading.

The degree of oxidation of manganese-heptoxid, and thus the oxidized hydrocarbons, can be determined calorimetrically based on the reaction heat.

In accordance with the foregoing inventions, the present invention provides a method for the detection and quantification of organic compounds, in particular hydrocarbons, characterized by

C _n X _{2n + 2} (where n is from 1 to 10, X represents chlorine and / or fluorine) and then, after the addition of the solvent affecting the solvent, manganese dissolved in said solvent, Heptoxide is added and, based on the color change of the manganese heptoxide, the presence of organic compound (s) and the amount of manganese heptoxide consumed in the oxidation of the organic compound (s) are calculated directly or indirectly.

Advantageously, the process according to the invention is characterized in that perchloric anhydride (C1 ₂ O ₇ ) is added to the system and the process is carried out in an "acidic" mixture.

Another preferred embodiment of the process according to the invention is characterized in that potassium persulfate is added to the system as an adjuvant and the process is carried out in a "neutral" mixture.

A further preferred embodiment of the process of the invention is characterized in that in the "acidic" mixture, the organic compound (s) is oxidized with a known amount of excess manganese heptoxide, and an iron compound (II) equivalent to Mn ₂ O ₇ is added. and determining the iron (II) residue by colorimetry or photometry in a manner known per se.

Another preferred embodiment of the process of the invention is characterized in that the oxidation reaction is carried out in a calorimeter and the amount of Mn ₂ O ₇ reacted and the amount of the oxidized organic compound (s) is calculated from the amount of heat released.

HU 217 029 A

The invention further relates to a reagent for the detection and measurement of organic compounds, in particular hydrocarbons, characterized in that n = 1 to 10 carbon atoms

C _n X _{2n + 2} can be represented by the general formula of organic solvent, in which X is chlorine and / or fluorine, and which solvent comprises from 0.02 to 200 g / 1 of manganese heptoxidot (Mn ₂ O ₇₎ dissolved therein.

The reagent of the invention is preferably characterized in that the amount of dissolved Mn ₂ O ₇ is 20-120 g / l.

Preferably, the reagent of the present invention is characterized in that it has an organic compound content up to 0.1 mg / L that can be oxidized by manganese heptoxide.

Preferably, the reagent of the invention is characterized in that it has a water content of up to 5 mg / l.

The invention will be described in more detail by way of examples, without, however, limiting the scope and scope of the invention to the examples presented.

Example 1: Mn ₂ O ₇ reagent

A solvent such as _CCI4 cent equilibrated manganese heptoxiddal until free of organic material, a reducing agent and then with distilled water washed until free of Mn (P93 00381 application method described in Hungarian).

Under 200 mL of purified CCl ₄ , 20 mL of cc H ₂ SO ₄ alt. Was layered and then 7.3 g of KMnO ₄ (alp.) Was added gradually, with complete dissolution. The resulting manganese heptoxide completely passes into the carbon tetrachloride phase. (Based on the partition coefficient, the migration is practically complete.) After separation of the sulfuric acid and CCl ₄ phases, the solvent phase is decanted from the acid. Dry over P ₂ O _{5 for} one day and store in a brown ground glass stopper. This gives a 0.1 molar solution of manganese heptoxide in carbon tetrachloride (22 g / l).

From this solution, a 0.01 M solution was diluted with CCl ₄ .

Example 2: Mn ₂ O ₇ reagent for calorimetry

Prepare the reagent as in Example 1, but with the following modified ratios:

100 ml purified carbon tetrachloride, ml cc sulfuric acid alt. and 25 g of potassium permanganate alt.

Example 3: Cleaning of the vessels used

The vessels used in each test should be free of organic compounds. Flushing solution used: 15 g KMnO ₄ dissolved in 1 liter cc H ₂ SO ₄ . After the rinsing solution, rinse the dishes with tap water, then with dilute sulfuric acid H ₂ O ₂ , then again with tap water and distilled water.

Example 4: Determination of hydrocarbons from soil For the test, the soil to be analyzed is prepared as follows:

5 g of the sample soil is suspended in 20 ml of purified CCl ₄ . Under ice-cooling, 10 ml of a solution of persulfate (10% w / w solution of K ₂ S ₂ O _{8 in} cc H ₂ SO ₄ ) is added. The suspension is shaken repeatedly until it foams under agitation. It is then sedimented, the solvent phase is discarded and tested according to one of the following examples.

Example 5: Determination of hydrocarbons from air

In a properly selected absorber vessel, called an impinger (which is a 20 ml test-tube glass vessel with a ground-glass stopper which can be connected to a vacuum and has a lateral opening at the outside, a capillary extending to the bottom of the vessel to form a siphon; -1.0 mm ² ) 3 ml of carbon tetrachloride are prepared and 1 ml of cc H ₂ SO _{4 is} layered underneath. Not more than one liter of air to be tested, but always a known volume, is bubbled through the liquid phases to a maximum of one liter. At a flow rate of 100 ml / min. The hydrocarbons to be examined are absorbed in the CCl ₄ phase and can be determined.

In practice, it is a more reliable solution to add to the impinger a known amount of reagent prior to aspirating the air, and measuring the volume of air having a hydrocarbon content equivalent to the premixed reagent when aspirating the air.

5a. Example 1: The air to be tested has a hydrocarbon content of at least 0.05 mg / L; to the impinger were added 3 mL of CCl ₄ and 1 mL of a 1: 1 mixture of cc HClO ₄ and cc H ₂ SO ₄ and 2.5 mL of a 0.01 M solution of Mn ₂ O _{7 in} carbon tetrachloride. Air aspiration is continued until the pink color of Mn ₂ O ₇ disappears. The volume of air drawn through is then read. The determination of the hydrocarbon content is accurate to ± 10%.

5b. Example 1: The air to be tested has a hydrocarbon content of at least 0.015 mg / L; 3 ml of CCl ₄ , 1 ml of a 10% solution of K ₂ S ₂ O ₈ cc H ₂ SO ₄ and 2.5 ml of a 0.01 M solution of Mn ₂ O _{7 in} carbon tetrachloride were added to the impinger. The filtration was continued until the carbon tetrachloride phase had decolorized. The hydrocarbon contamination of the air is calculated from the volume drawn through. The accuracy of the measurement is ± 10%.

When examining the air in the soil, a cavity is dredged into the soil and the air sampled is lowered into the cavity. In this case, it is advisable to combine the impinger with a photoelectric light unit which, for operators, will electronically indicate the colorlessness of the absorbent.

In the following examples, the following simplified notations are used for the solutions used:

Mn-ox .: 0.01 M Mn ₂ O _{7 in} carbon tetrachloride, freshly prepared by dilution with CCl ₄ before use

Example 1.

Perchlorate: 70% w / v HClO ₄ / cc H ₂ SO ₄ (1: 1).

HU 217 029 A

Persulfate: 10% w / w solution of K ₂ S ₂ O _{g in} cc H ₂ SO ₄ .

Example 6: Qualitative detection of hydrocarbons

Before quantification, it is often necessary to carry out many simple preliminary measurements in the field to delimit the contaminated area and to uncover the pollutant foci.

6a. example: Detection in neutral medium

To 3 ml of the sample collected in carbon tetrachloride according to Examples 4 or 5 is added 0.02 ml Mn-ox. And compared with a blank prepared with CCl ₄ .

At a contamination level above 1 mg / l, the test shows a tan color.

6b. Example 1: Detection in acidic medium of a sample of carbon tetrachloride

Perchlorate (0.15 mL) was added and the mixture was shaken

0.02 mL of Mn-ox. and shaking vigorously again.

At a contamination level above 1 mg / l, the assay is discolored compared to a blank prepared similarly with pure CCl ₄ .

The sensitivity of the assay can be enhanced by adding 3 to 3 ml of distilled water to both the assay and the blank at the end of the assay and shaking with it. The color difference is visible in the aqueous phase. The detection sensitivity is thus above 2 mg / l.

Example 7: Determination by titrimetry ml of CCl ₄ in the test solution per ml of perchlorate were mixed, and the gradual feed, Mn was added until ox. was repeated while shaking, until the carbon tetrachloride phase is permanently pink.

The determination may be carried out in a neutral medium:

ml CCl ₄ w solution containing test compound, mixture mL Persulfate supra Mn ox. titrated with permanent pink color.

It can be used in concentrations of 10-1000 mg / l (see Annex 1).

The accuracy is within ± 5% between 50-500 mg / l.

Example 8: Colorimetric (photometric) determining ml CCl ₄ solution to the solution containing the test substance

Perchlorate (0.15 mL) was added and shaken then

0.05 mL of Mn-ox. Is added and shaken again.

A volume of Fe (II) solution equivalent to 0.05 ml Mn-ox., Which was previously tested in a blank test, was then added, which was 39.3 g Fe (NH ₄ ) ₂ (SO ₄ ) .6H ₂ O and 50 ml 85 by weight dissolution of H ₃ PO _{4 in} water and making up to 1 liter, followed by an aliquot

Made with 100% dilution. [The Fe (II) salt solution used is 0.1 M in Fe ²⁺ .]

Shake vigorously and then test

0.5 ml of 1% α, α'-dipyridyl sulfate and 200 ml of ammonium acetate 200 g / l are added.

In colorimetry, the resulting color is compared to the color scale of a comparative test series made with n-hexane; for photometry, the sample is diluted ten-fold with distilled water and read its extinction at 522 nm against a blank. Record the required calibration curve using n-hexane (see Annex 1).

In both solutions, a measurement accuracy of ± 25% can be achieved within a concentration range of 0.5 to 10 mg / l.

Example 9: Calorimetric determination

The calorimeter 1 of Figure 1 is used, the essence of which is a reaction vessel 2 inserted into a Dewar flask 3 and sealed with a ground glass stopper 4 with a dispensing opening 5 and soldered to two wires 6. The wires 6 extend into the reaction vessel 2 and have a heat sensor 7 at their ends. Reaction vessel 2 is spherical, having a volume of 10-25 ml and made of glass with a wall thickness of 0.1 mm or less. The wires 6 are electrically insulated throughout. The temperature sensor 7 is a thermistor or a temperature sensor diode. The wires 6 are connected to a known electronic signal acquisition and processing unit.

To carry out the measurement, the carbon tetrachloride solution containing the test substance is poured into the reaction vessel 2. Calorimeter 1 is assembled and excess Mn ₂ O ₇ prepared as in Example 2 is added to the carbon tetrachloride solution through an inlet port 5 in an amount such that Mn (VII) is in excess of the test substance. The amount of test substance is calculated based on the reaction heat generated. In our experience, the temperature increase is linearly proportional to the hydrocarbon concentration.

The determination is accurate to within ± 10% within the hydrocarbon concentration range of 50 to 1000 mg / l.

The upper concentration limit is limited by the boiling point of carbon tetrachloride. At a concentration of 2.5 g / l n-hexane, CCl ₄ boils from the heat of reaction (see Annex 2).

The present invention provides a rapid, inexpensive and simple solution to the detection and quantification of organic contaminants in general, and hydrocarbons in particular, compared to conventional analytical and instrumental measurement techniques known in the art.

The advantages of the method of the invention are particularly evident in on-the-spot field inspections, as they require little equipment and require neither electricity nor gas. This is a great help for large-scale environmental inspections on the spot, even in areas not accessible by car.

A further advantage of the method of the invention is that it is based on a rapid reaction at room temperature and that the reagent used is stable and transportable. The assay adap4

EN 217 029 Can be used for conventional titrimetric, colorimetric, photometric methods.

Annex 1

DATA FOR CALCULATION OF TITRATION (in "acidic" medium) Moles of Mn ₂ O ₇ are oxidized to exactly 1 mole of n-hexane, ie 1 ml of a 0,01 M solution of Mn ₂ O _{7 contains} 0,86 mg of n-hexane. The specific weight loss depends on the amount and order of carbon atoms in the hydrocarbon, open or branched, saturated or unsaturated, cyclic or aromatic, etc.

Equivalents of some hydrocarbons with n-hexane:

CH method Specific weight loss mg CH / ml [1 ml 0.01 m.Mn, O ₇ oxidized CH (mg)] n-hexane equivalent n-hexane 0,860 1,000 cyclohexane 1,050 0.819 n-heptane 1,000 0,860 i-octane 0.713 1,207 Benzene 0,650 1,323 Toluene .657 1.309 Petrol 98 ' 0,992 0.867 Kerosene 0.915 0.940

These data can also be used for photometry. Annex 2

CALORIMETRIC CALCULATION PROCEDURE Specific heat of reaction for some hydrocarbons:

CH method Qf j / mg n-hexane equivalent n-hexane 23.1 1,000 cyclohexane 23.7 1,026 n-heptane 22.3 0,965 i-octane 13.9 0.602 Petrol 98 ' 21.5 0.931 fuel oil 20.4 0.883 Lube 16.7 .723 Gyertyapa- RAFFIN 20.6 .892

V'P'C

CH _mg = _T - ^ - _where

CH is the quantity of hydrocarbon measured, mg

T is the increase in temperature, ° C v is the volume of solvent (CH solution added + reagent), ml p is the density of the solvent, g / cm ³ c is the specific heat of the solvent, j / g ° C

Q _{f is} the specific heat of reaction, j / mg.

T can be obtained as the difference between T, the temperature at the moment of mixing of the CH solution + the reagent and the temperature T ₂ measured after the reaction time: T = T ₂ -T ,.

T _b when the input solution and the reagent CH realizable different temperatures, only a calculation:

^V CH + ^v rv _{CH is} the volume in ml of the CH solution injected

T _{CH is} the temperature of the CH solution introduced, ° C v _{r is} the volume of reagent added, ml

T _{r is} the temperature of the reagent added, ° C.

If the volume of reagent added is preferably a fraction of the volume of CH solution injected, the relationship is simplified as follows:

Τ, = χτ _α , +% T _r .

Since the wall thickness of the vessel minimal defects caused by water and the resulting value present in addition to CCl _4, and the resulting components at CCl ₄ different specific heat from error - neglected - due to the relatively low concentration and small fajhőkülönbség.

Claims (13)

PATENT CLAIMS A process for the detection and quantification of organic compounds, in particular hydrocarbons, characterized in that the organic compounds are taken up in an open or cyclic C 1-10 saturated perchlor or perfluorine or perchlorofluorocarbon solvent and optionally adding a peroxide compound or strong acid anhydride to the mixture, then adding manganese heptoxide dissolved in said solvent and calculating the amount of organic compounds in the sample by measuring the presence of organic compounds on the basis of the color change of the solution or measuring the organic compounds oxidation. 2. A process according to claim 1, wherein the peroxide compound is potassium peroxodisulfate dissolved in sulfuric acid. 3. The process according to claim 1, wherein the acid anhydride is chloro-heptoxide. A process according to claim 1 or 2, characterized in that the soil sample containing the organic matter (s) is suspended in said solvent and after the addition of the peroxide compound, the suspension is shaken repeatedly until foaming. 5. A process according to any one of claims 1 to 5, wherein the air sample containing the organic material (s) is bubbled through a solvent containing a peroxide compound or anhydride and a known amount of manganese heptoxide, and the excess manganese heptoxide is determined in the mixture. 6. A process according to claim 1, wherein the solvent mixture containing the organic substance (s) is placed in a calorimeter, excess manganese hexoxide solution is added and the amount of organic substance (s) is calculated from the resulting heat of reaction. HU 217 029 A 7. Reagents for the detection and quantification of organic compounds, in particular hydrocarbons, characterized in that the fully or halogenated perchloric or perfluorocarbon saturated carbon monoxide solvent is from 1 to 10 grams per liter of manganese heptoxide contains dissolved. The reagent of claim 7, wherein the amount of dissolved manganese heptoxide is 20 to 120 g / l. The reagent according to claim 7 or 8, characterized in that the organic compound to be oxidized by manganese heptoxide is not more than 0.1 mg / l. 10. A reagent according to any one of claims 1 to 3, characterized in that its water content is up to 5 mg / liter. 11. Calorimeter for quantifying organic compounds, in particular hydrocarbons, by reaction vessel fitted in a Dewar flask, characterized in that the reaction vessel (2) is provided with a polished dispensing port (5). It is sealed with 5 glass stoppers (4), and the reaction vessel (2) has a temperature sensor (7) soldered to the polished glass stopper (4) and provided with wires (6). Calorimeter according to claim 11, characterized in that the reaction vessel (2) is preferably made of glass 10 made - spherical with a wall thickness of 0.1 mm or less. Calorimeter according to claim 11 or 12, characterized in that the thermo-sensor (7) is a thermistor or a thermo-sensitive diode and the wires (6) themselves are connected to an electronic signal acquisition and processing unit.