Method for estimating the amount of source components in deposits

Abstract

To provide a method for quantitating respective components in a deposit and estimating an amount ratio of generation sources of respective components.SOLUTION: An estimation method of an origin component amount in a deposit comprises: an organic solvent extraction step of performing organic solvent extraction to the deposit being a measurement target, and acquiring a solid component which is an insoluble matter, and a soluble matter; a classification step of classifying the solid component obtained in the organic solvent extraction step, into an organic carbon component, an inorganic carbon component and a metal component; a quantitation step of quantitating an aromatic component and an aliphatic component in the organic carbon component; and an estimation step of, in an amount ratio of the quantified aromatic component and the aliphatic component, estimating a value of a ratio of the aromatic component as a component amount which is originated from raw material gasoline in the solid component of the deposit, and estimating a value of a ratio of the aliphatic component as a component amount originated from a raw material engine oil in the solid component of the deposit.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a method for estimating the amount of origin components in a deposit, and more particularly to a method for estimating the amount of origin components in a deposit that accumulates inside a gasoline engine. [Background technology]

[0002] As a car is driven, deposits gradually build up inside the gasoline engine. These deposits are products of incomplete combustion of raw gasoline or engine oil. If these deposits accumulate excessively, they can, for example, adversely affect drivability and also lead to the emission of large amounts of air pollutants into the atmosphere from the car.

[0003] In order to suppress and / or prevent the accumulation of these deposits, various studies have been conducted.

[0004] For example, Non-Patent Document 1 describes a method for estimating the source of a deposit (specifically, the raw gasoline and engine oil) based on the properties of the deposit. In this method, first, various analytical methods (specifically, infrared spectroscopy, electron probe microanalysis, thermogravimetry, and solvent extraction) are used to obtain analytical results (analysis results related to chemical structure, elemental composition, thermogravimetric properties, and solubility) related to the properties of the deposit to be measured. Next, the obtained analytical results are compared with analytical indicators that summarize chemical information such as the above-mentioned chemical structure, to determine whether the deposit is derived from the raw gasoline or the engine oil.

[0005] Here, the analytical index is created using a matrix table. Specifically, the columns of the matrix table list components specific to the feed gasoline (i.e., HC heavy fraction, aliphatic HC oxides, aromatic HC oxides, and HC carbides) and components specific to the engine oil (i.e., fine oxides, partial oxides, and high oxides). Meanwhile, the rows of the matrix table list chemical information regarding the chemical structure, elemental composition, thermogravimetric properties, and solubility of each of those components.

[0006] Specifically, the comparison of the obtained analysis result with the analysis index is performed by confirming which component in the analysis index the chemical structure, elemental composition, thermogravimetric properties, and solubility chemical information the obtained analysis result resembles. If the analysis result resembles any of the components specific to the feedstock gasoline, it is determined that the component originates from the feedstock gasoline, and if the analysis result resembles any of the components specific to the engine oil, it is determined that the component originates from the engine oil. [Prior art documents] [Non-patent literature]

[0007] [Non-Patent Document 1] Yasuo Esaki, “Analysis of Engine Deposit Properties”, Journal of the Combustion Society of Japan, 2014, Vol. 56, No. 178, pp. 308-316 Summary of the Invention [Problem to be solved by the invention]

[0008] In Non-Patent Document 1, the analysis results concerning the properties of the deposit being measured (i.e., the qualitative analysis results) are compared with the analysis indicators concerning the properties of the deposit (qualitative analysis indicators), and therefore it is only possible to determine whether the deposit being measured originates from the raw gasoline or the engine oil.

[0009] In other words, it is not possible to determine what proportion (amount) of the composition derived from the raw gasoline and what proportion (amount) of the composition derived from the engine oil is accounted for in the deposit (the object to be measured).In other words, it is not possible to quantitatively determine the deposit (the object to be measured).

[0010] Here, unlike qualitative judgment, quantitative judgment allows the source of deposits to be considered with priority. For example, if 30% of the deposits are derived from raw gasoline and 70% are derived from engine oil, it can be understood that engine oil should be considered with priority. This priority consideration can significantly improve the cost-effectiveness of deposit consideration.

[0011] SUMMARY OF THE PRESENT EMBODIMENT In view of the above problems, an object of the present invention is to provide a method for quantifying each component in a deposit and estimating the quantitative ratio of the sources of each component. [Means for solving the problem]

[0012] The present invention was developed based on the discovery that the quantitative ratio of origin components can be calculated from the quantitative ratio of aromatic components to aliphatic components of the organic carbon components in deposits accumulated in gasoline engines.

[0013] That is, the above object is achieved by the present invention. an organic solvent extraction step of extracting the deposit, which is the object to be measured, with an organic solvent to obtain an insoluble solid component and a soluble component; a classification step of classifying the solid component obtained in the organic solvent extraction step into an organic carbon component, an inorganic carbon component, and a metal component; A quantitative determination step of determining aromatic components and aliphatic components in the organic carbon components; an estimation step of estimating the ratio value of aromatic components in the quantitatively determined ratio of aromatic components to aliphatic components as the amount of components originating from the raw material gasoline in the solid component of the deposit, and estimating the ratio value of aliphatic components as the amount of components originating from the raw material engine oil in the solid component of the deposit; This can be achieved by a method for estimating the amount of an origin component in a deposit, comprising:

[0014] In a preferred embodiment of the method for estimating the amount of origin component in a deposit according to the present invention, the classification step is carried out by measuring the change in weight of the solid component due to heating (hereinafter referred to as thermogravimetry).

[0015] According to another preferred embodiment of the method for estimating the amount of an original component in a deposit according to the present invention, the thermogravimetric measurement includes a heating operation under an inert gas atmosphere in which the solid component is heated to at least 900° C. under an inert gas atmosphere; In the classification step, a mass ratio of the mass of the solid components pyrolyzed in the heating operation under the inert gas to the total mass of the solid components is obtained as a ratio of the classified organic carbon components.

[0016] According to yet another preferred embodiment of the method for estimating the amount of origin components in a deposit according to the present invention, the thermogravimetric measurement includes a heating operation in an air atmosphere in which the solid component is heated in an air atmosphere until the organic carbon component and the inorganic carbon component are completely vaporized, In the separation step, the mass ratio of the solid components remaining after the heating operation in an air atmosphere to the total mass of the solid components is obtained as the ratio of the metal components.

[0017] According to yet another preferred embodiment of the method for estimating the amount of an origin component in a deposit according to the present invention, the quantitative determination step comprises: 13 Includes C-NMR analysis.

[0018] According to yet another preferred embodiment of the method for estimating the amount of an origin component in a deposit according to the present invention, the quantitative determination step further includes a metal content quantitative operation for quantifying each metal content by performing elemental analysis on the solid component, The estimation process includes an operation of estimating the amount of each metal component, which estimates the amount of components originating from the raw gasoline and the amount of components originating from the raw engine oil in the solid components of the deposit for each of the quantified metal components.

[0019] According to yet another preferred embodiment of the method for estimating the amount of an origin component in a deposit according to the present invention, the organic solvent used in the organic solvent extraction is hexane. Effect of the Invention

[0020] According to the present invention, it is possible to estimate the quantitative ratio of components derived from the feed gasoline and the quantitative ratio of components derived from the engine oil, at least in the organic carbon components in the deposit.

[0021] These ratios can indicate which source the deposits are primarily from and therefore can be used to prioritize problematic sources, which can greatly improve the cost-effectiveness of deposit containment and / or prevention efforts. [Brief description of the drawings]

[0022] [Figure 1] 1 is a flowchart for explaining an overview of a method for estimating the amount of origin components in a deposit according to the present invention. [Diagram 2] 13A is a pie chart showing the results of estimating the amount of origin components in deposits in the intake port, and FIG. 13B is a pie chart showing the results of estimating the amount of origin components in deposits on the piston crown surface. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0023] <Method of estimating the amount of origin components in deposits> As shown in FIG. 1, the method for estimating the amount of an origin component in a deposit according to the present invention includes an organic solvent extraction step (S100), a classification step (S110), a quantification step (S120), and an estimation step (S130).

[0024] [Organic solvent extraction step (S100)] In this process, the deposit to be measured is subjected to organic solvent extraction to obtain the insoluble solid components and the soluble components.

[0025] The deposits to be measured are deposits that gradually build up inside a gasoline engine as the vehicle is driven.

[0026] The organic solvent used in the organic solvent extraction may be any, but examples thereof include toluene, xylene, methylene chloride, hexane, and combinations of one or more of these. Among these, it is preferable that the organic solvent is hexane (the organic solvent extraction step (S100)).

[0027] [Classification process (S110)] In the classification step, the solid components obtained in the organic solvent extraction step (S100) are classified into organic carbon components, inorganic carbon components, and metal components, each of which is expressed as a mass ratio of each component to the total mass of the solid components of the deposit.

[0028] The classification step is preferably carried out by a thermogravimetric measurement of the solid components, which can measure the weight change of trace components and can adjust the heating rate. Specific examples of the method include TGA, TG-DTA, and TG-MS analysis.

[0029] This thermogravimetry includes a heating operation under an inert gas atmosphere in which the solid component is heated to at least 900°C under an inert gas atmosphere, and the classification step obtains the mass ratio of the pyrolyzed solid component pyrolyzed in the heating operation under an inert gas atmosphere to the total mass of the solid component as the mass of the classified organic carbon component.

[0030] Specifically, the heating operation under an inert gas atmosphere is an operation in which the solid component of the deposit is heated under an inert gas atmosphere (e.g., under a helium atmosphere or a nitrogen atmosphere) to at least 900°C (preferably 900°C to 1000°C, more preferably 900°C to 950°C, and particularly preferably 900°C).

[0031] This heating is performed, for example, by starting from room temperature (e.g., 23° C.) and increasing the temperature at a typical rate (e.g., 10° C. / min) until the target temperature (e.g., 900° C.) is reached. It is preferable not to hold the temperature at a certain temperature during the temperature increase to the target temperature for a certain period of time. This is because, if the temperature is held for a certain period of time, there is a risk that inorganic carbon components as well as organic carbon components will be thermally decomposed.

[0032] This target temperature can be determined by performing solid-state NMR measurement on the residue after thermogravimetry. The temperature at which no peak derived from the sample is detected in the measurement results can be the target temperature. In addition, the weight loss up to this target temperature under an inert gas atmosphere can be regarded as the mass ratio of the organic carbon component in the solid component of the deposit.

[0033] Furthermore, it is preferable that the thermogravimetric measurement includes a heating operation in an air atmosphere in which the solid component is heated in an air atmosphere until the organic carbon component and the inorganic carbon component are completely vaporized, and the separation step obtains the mass ratio of the remaining solid component remaining in the heating operation in an air atmosphere relative to the total mass of the solid components as the ratio of the metal component.

[0034] The heating operation in an air atmosphere is performed, for example, by starting from room temperature (e.g., 23°C) and increasing the temperature at a general rate (e.g., 10°C / min) or by increasing the temperature stepwise until the target temperature is reached.

[0035] This target temperature is preferably 900 to 1000°C, more preferably 900 to 950°C, and particularly preferably 900°C.

[0036] The mass of the solid components remaining after the heating operation in the air atmosphere can be regarded as the mass of the metal components, i.e., the ratio of the mass of the remaining solid components to the total mass of the solid components of the deposit can be regarded as the ratio of the mass of the metal components to the total mass of the solid components of the deposit.

[0037] For the above thermogravimetry, a commercially available thermogravimetry instrument can be used, such as TG-DTA2000SA (manufactured by Bruker A.X.), Thermo plus EVO2 differential thermobalance (manufactured by Rigaku Corporation), or TG / DTA6300 (manufactured by Hitachi High-Tech Science Corporation).

[0038] When the thermogravimetric measurement includes both a heating operation under an inert gas atmosphere and a heating operation under an air atmosphere, and the mass proportions of the organic carbon components and metal components in the solid components have been estimated, the mass proportion of the inorganic carbon components can be determined by subtracting the mass proportion of the organic carbon components and the mass proportion of the metal components from the mass proportion of the solid components of the deposit (this is the classification process (S110)).

[0039] [Quantification process (S120)] In this quantitative step, the amount of the solid component of the deposit is 13 C-NMR analysis (specifically, solid 13 C-NMR analysis).

[0040] this 13 C-NMR analysis can quantify the aromatic and aliphatic components in the organic carbon components.

[0041] The ratio of aromatic and aliphatic components in the organic carbon components is calculated by subtracting the blank area (for a single component such as quartz) from the area of ​​the solid components of the deposit, and taking the area of ​​200 to 75 ppm of the subtracted area as the ratio of aromatic components and the area of ​​75 to 0 ppm as the ratio of aliphatic components. The baseline is created by linearly approximating the charts of 250 to 200 and 0 to -50 ppm.

[0042] the above13 For C-NMR analysis, commercially available 13 A C-NMR analyzer can be used, for example, AVANCE 600 MHz (manufactured by BRUKER BIOSPIN) or ECA400 (manufactured by JEOL Ltd.).

[0043] It is also preferable that the quantitative determination step further includes a metal content quantitative operation of quantifying each metal content by performing elemental analysis on the solid component. The metal content quantitative operation is performed, for example, when the presence of a metal component is confirmed in the classification step.

[0044] By this elemental analysis, each metal constituting the metal component can be quantified. According to preferred embodiments of this elemental analysis, ICP-AES, ICP-MS, XRF, SEM-EDS, etc. are mentioned. Particularly preferred is ICP-AES.

[0045] The ratio of each metal constituting the metal component is calculated based on the mass of each metal component calculated as an oxide relative to the total mass of the metal component oxides (when all the metal components are oxidized).

[0046] For the above elemental analysis, a commercially available elemental analysis instrument can be used, such as SPECTRO BLUE (FMX26) (SPECTRO), ICPS-8100 (Shimadzu Corporation), ICPE-9820 (Shimadzu Corporation), SPS5100 (SII NanoTechnology), JED-2300 (JEOL Ltd.), etc. (all of the above is the quantification process (S120)).

[0047] [Estimation process (S130)] In this process, in the quantitative ratio of aromatic components to aliphatic components, the ratio value of aromatic components is estimated as the amount of components originating from the raw gasoline in the solid component of the deposit, and the ratio value of aliphatic components is estimated as the amount of components originating from the raw engine oil in the solid component of the deposit.

[0048] Furthermore, when the quantification step (S120) includes a metal content quantification operation for quantifying each metal content by performing elemental analysis on the solid components, the estimation step (S130) includes a component amount estimation operation for each metal content, for estimating the amount of components originating from the raw gasoline and the amount of components originating from the raw engine oil in the solid components of the deposit, respectively, for each of the quantified metal contents.

[0049] For each of the quantified metal contents, chemical information about metals present only in the raw gasoline (e.g., Mn, Pb, and Fe) and metals present only in the raw engine oil (e.g., Mo, Ca, P, and Zn) is used to estimate the amount of components originating from the raw gasoline and the amount of components originating from the raw engine oil in the solid components of the deposit.

[0050] That is, each metal component confirmed in the quantification step is compared with chemical information on the metals present only in the feed gasoline and the metals present only in the feed engine oil. In this comparison, the ratio of the oxide equivalent of the metals present only in the feed gasoline is estimated as the amount of components originating from the feed gasoline in the solid components of the deposit. Meanwhile, the ratio of the oxide equivalent of the metals present only in the feed engine oil is estimated as the amount of components originating from the feed engine oil in the solid components of the deposit (the above is the estimation step (S130)). EXAMPLES

[0051] The present invention will be specifically described below by showing examples, but the present invention is not limited to these examples.

[0052] <Example 1> In the first embodiment, the method for estimating the amount of origin components in a deposit according to the present invention was carried out on a deposit accumulated in an intake port.

[0053] [Separation of deposits into soluble and insoluble fractions using hexane extraction] 0.5044g of untreated deposits accumulated in the intake port were added to 30ml of hexane and ultrasonically treated for 15 minutes. The ultrasonically treated product was filtered through a filter with a pore size of 0.45μm. The concentrated filtrate was used as the soluble fraction of the hexane extraction. The filtration residue was used as the insoluble fraction of the hexane extraction.

[0054] The insoluble matter from the hexane extraction was dried in a vacuum drying device at 60°C for 1 hour to completely remove the hexane. The insoluble matter from which the hexane had been removed was taken as the solid component of the deposit.

[0055] The solid content of the deposit was 0.4081g. In other words, the ratio of the solid content of the deposit to the mass of the untreated deposit (0.5044g) was 80.9%. From this result, the hexane extractable soluble matter to the mass of the untreated deposit was 19.1%.

[0056] [Estimation of the amount of source components for soluble matter in hexane extraction] The soluble matter in the hexane extract was analyzed using the AL400 manufactured by JEOL Ltd. under general conditions for solution NMR. 13 C-NMR analysis and 1 H-NMR analysis was carried out.

[0057] 13 C-NMR analysis and 1 The H-NMR analysis results showed no peaks at 200 to 75 ppm and 8 to 7 ppm (peaks indicating the presence of aromatic components), indicating that the soluble matter in the hexane extract (19.1%) was a component originating from the raw engine oil (which does not contain aromatic components).

[0058] [Classification of the solid components of deposits into organic carbon components, inorganic carbon components, and metal components] A portion of the solid component of the deposit obtained by separating the deposit into soluble and insoluble components using the above hexane extraction method was used as a sample to perform TG-DTA analysis using a TG / DTA6300 manufactured by Hitachi High-Tech Science Corp. In this TG-DTA analysis, 0.001 g of the sample was heated in a nitrogen atmosphere from 40°C to 900°C at a heating rate of 10°C / min to obtain the results of the TG-DTA analysis.

[0059] In this result, the mass loss of the sample at 900°C, where the mass began to decrease drastically (i.e., the mass of the solid components thermally decomposed during heating up to 900°C), was taken as the mass ratio of the organic carbon components to the solid components of the deposit. This mass ratio of the organic carbon components was 45.3% of the sample (i.e., the mass ratio of the solid components of the deposit (80.9%)).

[0060] Furthermore, a part of the solid component of the deposit obtained by separating the deposit into soluble and insoluble parts using the above-mentioned hexane extraction method was used as a sample, and in order to completely combust the sample, a TG-DTA analysis was performed using a TG / DTA6300 manufactured by Hitachi High-Tech Science Corp. At that time, the atmosphere was changed from a nitrogen atmosphere to an air atmosphere, and the temperature was increased from 40°C to 900°C at a rate of 10°C / min.

[0061] The mass of the solid components remaining after the heating operation in the air atmosphere (i.e., the mass of the metal components) was taken as the mass ratio of the metal components to the solid components of the deposit, which was 13.6% with respect to the sample (i.e., the mass ratio of the solid components of the deposit (80.9%)).

[0062] The inorganic carbon content was calculated by subtracting the mass percentage of the organic carbon content (45.3%) and the mass percentage of the metal content (13.6%) from the mass percentage of the solid content of the deposit (80.9%). The inorganic carbon content was 22.0%.

[0063] [Estimation of the amount of organic carbon components] A part of the solid component of the deposit obtained by separating the deposit into soluble and insoluble parts using the above hexane extraction method was used as a sample, and the ECA400 manufactured by JEOL Ltd. was used to measure the 13 C-NMR analysis was performed. 13 Only aromatic and aliphatic components in the organic carbon components were measured by C-NMR analysis.

[0064] The ratio of aromatic and aliphatic components in the organic carbon components was calculated by subtracting the blank area (for a single component such as quartz) from the area of ​​the sample analysis result, and then calculating the ratio of aromatic components from 200 to 75 ppm in the area after the blank was subtracted, and the ratio of aliphatic components from 75 to 0 ppm. The ratio of aromatic components to aliphatic components was 21.9:23.4.

[0065] [Estimation of the amount of metal components] A portion of the solid component of the deposit obtained by separating the deposit into soluble and insoluble fractions using the above-mentioned hexane extraction method was used as a sample and subjected to ICP-AES analysis using an SPS5100 manufactured by SII Technology and an ICPE-9820 manufactured by Shimadzu Corporation.

[0066] As a result, only elements present only in the raw engine oil were detected. Mo atoms, Ca atoms, P atoms, and Zn atoms (present only in the raw engine oil) accounted for 0.3%, 2.1%, 0.3%, and 0.3% of the metal oxide components of the sample, respectively. In other words, atoms present only in the raw engine oil accounted for 3.0% of the mass proportion of the metal components (13.6%).

[0067] Therefore, the proportion of components originating from the raw engine oil out of the total metal components (13.6%) was 3.0%.

[0068] [summary] The amount of components originating from the raw gasoline was 21.9%, present only in the organic carbon components (45.3%).

[0069] The amount of components originating from the raw engine oil was 23.4% of the organic carbon components (45.3%) and 3.0% of the metal components (13.6%). In other words, the total amount of components originating from the raw engine oil was 26.4%.

[0070] It was not possible to identify the origin of the inorganic carbon components.

[0071] The remainder (10.6%) of the metal components (13.6%) came from sources other than the raw gasoline and raw engine oil.

[0072] Regarding the above respective proportions, if the amount of solid components in the deposit, 80.9%, is converted to 100%, the amount of components originating from the raw engine oil was 32.6%, the amount of components originating from the raw gasoline was 27.0%, the amount of components whose origin could not be identified was 27.2%, and the amount of components originating from sources other than the raw gasoline and raw engine oil was 13.1% (see Figure 2(a)).

[0073] <Example 2> In Example 2, the same estimation method as in Example 1 was used, except that the deposits accumulated in the intake port were replaced by deposits accumulated on the piston crown surface.

[0074] Of the 100% solid components in the deposit, 45.0% were derived from the raw engine oil, 26.9% from the raw gasoline, 5.8% were derived from components whose origin could not be identified, and 22.3% were derived from sources other than the raw gasoline and raw engine oil (see Figure 2(b)).

[0075] As is clear from the results of Example 1, the solid components of the deposits accumulated in the intake port contained approximately the same amount of components originating from the raw engine oil (32.6%) and the raw gasoline (27.0%). Therefore, it was found that for deposits accumulated in the intake port, it is necessary to consider the raw engine oil and raw gasoline to the same extent.

[0076] On the other hand, in the case of deposits accumulated on the piston crown surface, as is clear from the results of Example 2, the solid components of the deposits contained a greater amount of components originating from the raw engine oil (45.0%) than from the raw gasoline (26.9%). In other words, it was found that in the case of deposits accumulated on the piston crown surface, it was necessary to give priority to the raw engine oil.

Claims

1. an organic solvent extraction step of extracting the deposit, which is the object to be measured, with an organic solvent to obtain an insoluble solid component and a soluble component; a classification step of classifying the solid component obtained in the organic solvent extraction step into an organic carbon component, an inorganic carbon component, and a metal component; a quantitative determination step of quantifying aromatic components and aliphatic components in the organic carbon component, the quantitative ratio of aromatic components to aliphatic components being calculated by subjecting the solid component to 13C-NMR analysis, subtracting a blank area from the area of ​​the 13C-NMR analysis result of the solid component, and determining the area from 200 to 75 ppm in the area from which the blank has been subtracted as the proportion of aromatic components and the area from 75 to 0 ppm as the proportion of aliphatic components; an estimation step of estimating the ratio value of aromatic components in the quantitatively determined ratio of aromatic components to aliphatic components as the amount of components originating from the raw material gasoline in the solid component of the deposit, and estimating the ratio value of aliphatic components as the amount of components originating from the raw material engine oil in the solid component of the deposit; A method for estimating the amount of origin components in a deposit, comprising:

2. 2. The method of claim 1, wherein the classification step is performed by thermogravimetry of the solid components.

3. The thermogravimetric measurement includes heating the solid component to at least 900° C. under an inert gas atmosphere; The estimation method according to claim 2, characterized in that the classification step obtains a mass ratio of the mass of the pyrolyzed solid components pyrolyzed by the heating operation under the inert gas atmosphere to the total mass of the solid components as the ratio of the classified organic carbon components.

4. The thermogravimetric measurement includes a heating operation in an air atmosphere in which the solid component is heated in an air atmosphere until the organic carbon component and the inorganic carbon component are completely vaporized; 4. The method according to claim 2, wherein the classification step obtains, as the proportion of the metal component, a mass ratio of the solid components remaining after the heating operation in an air atmosphere to a total mass of the solid components.

5. The quantitative determination step further includes a metal content determination operation of quantifying each metal content by performing elemental analysis on the solid component, The estimation method according to any one of claims 1 to 4, characterized in that the estimation step includes an operation of estimating the amount of each metal component, which estimates, for each of the quantified metal components, the amount of components originating from the raw gasoline and the amount of components originating from the raw engine oil in the solid components of the deposit.

6. The method according to any one of claims 1 to 5, characterized in that the organic solvent used in the organic solvent extraction is hexane.

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