CN111289403B - Method for analyzing content of gelatinizing agent in colloid propellant - Google Patents
Method for analyzing content of gelatinizing agent in colloid propellant Download PDFInfo
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- CN111289403B CN111289403B CN201811501460.7A CN201811501460A CN111289403B CN 111289403 B CN111289403 B CN 111289403B CN 201811501460 A CN201811501460 A CN 201811501460A CN 111289403 B CN111289403 B CN 111289403B
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- G01N5/04—Analysing materials by weighing, e.g. weighing small particles separated from a gas or liquid by removing a component, e.g. by evaporation, and weighing the remainder
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- G—PHYSICS
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Abstract
The invention relates to a propellant component content analysis technology, in particular to an analysis method for the content of a gelatinizing agent in a colloid propellant. The method comprises the steps of adding a certain amount of organic solvent into a colloid propellant sample, wherein a gelling agent in the colloid propellant is separated out because the gelling agent is insoluble in the selected organic solvent. Meanwhile, the added organic solvent can also react with all or part of other components except the gelling agent in the colloid propellant, and the reaction product and other components in the sample which do not react with the added organic solvent except the gelling agent can be dissolved in the added organic solvent, so that the independent separation and determination of the gelling agent are realized. The method provided by the invention overcomes the defects of the prior art scheme in the content analysis of the gelling agent of the salt-containing colloid propellant, and can be suitable for the analysis of colloid propellants with more types and more complex compositions.
Description
Technical Field
The invention relates to a propellant component content analysis technology, in particular to an analysis method for the content of a gelatinizing agent in a colloid propellant.
Background
Colloidal propellants are a new class of propellants developed on the basis of liquid propellants, which can be prepared by adding small amounts of gelling agents to conventional liquid propellants to cause the liquid propellants to gel. The colloid propellant combines the advantages of liquid propellant and solid propellant to a certain extent, and has the advantages of high specific impulse, adjustable thrust, multiple starting and other use performances of the liquid propellant, and the advantages of the solid propellant in the aspects of convenient storage and transportation, difficult volatilization and leakage and the like.
In colloidal propellants, the gelling agent is a key component in achieving the gelling of the liquid propellant. In hydrazine/hydroxylamine colloid propellants, high molecular compounds such as cellulose derivatives, polyvinyl alcohol, polyacrylamide and the like having good solubility in the corresponding liquid propellants are often used as gelling agents. The content of the gelling agent in the colloidal propellant has important influence on the rheological, atomization, combustion and other properties of the colloidal propellant, so that it is necessary to establish a corresponding analysis method of the content of the gelling agent in the colloidal propellant so as to perfect the quality control of the colloidal propellant.
When the content of the gelatinizer in the colloidal propellant prepared by the traditional hydrazine liquid fuel such as anhydrous hydrazine, methyl hydrazine, and unsymmetrical dimethylhydrazine is analyzed, the volatilizable hydrazine substances in the colloidal propellant can be removed by using a reduced pressure distillation mode so as to separate the gelatinizer and weigh and calculate the content. However, with the development of liquid propellant fuels, the components contained therein are increasingly complex, and salts formed by hydrazine, hydrazine derivatives, hydroxylamine and the like and inorganic acids or small-molecule organic acids are beginning to be used in liquid propellant fuels to improve the energy density, specific impulse, low-temperature start-up and the like thereof. In the corresponding colloidal propellants, the salts mentioned above, because of their non-volatility, cannot be separated from the gelling agent by distillation under reduced pressure.
Disclosure of Invention
The invention aims at overcoming the defects of the prior art and providing an analysis method capable of measuring the content of a gelling agent in a colloid propellant, in particular a salt-containing colloid propellant.
In order to achieve the above purpose, the invention adopts the following technical scheme:
a method of analyzing the gellant content of a colloidal propellant, comprising:
the colloid propellant contains a liquid propellant and the gelling agent, wherein the liquid propellant contains one or more of hydrazine, hydrazine derivative with amino group and hydroxylamine, and/or one or more of nitrate, hydrochloride, sulfate, phosphate, acetate, formate and oxalate of the above substances;
adding an organic solvent into the colloid propellant, wherein the organic solvent contains aldehyde and/or ketone compounds;
the organic solvent may react with all or a portion of the other components of the colloidal propellant other than the gellant, the reaction product being soluble in the organic solvent, such as components of the colloidal propellant other than the gellant that are not reactive with the organic solvent, and the components may be soluble in the organic solvent;
the gelling agent in the colloid propellant is separated out by itself because it is insoluble in the organic solvent, and the content of the gelling agent in the colloid propellant is calculated by weighing after separating it.
The gelling agent is a high molecular gelling agent.
The high molecular gelatinizer is one or more selected from cellulose derivative, dextran, glucomannan, chitosan, starch, dextrin, guar gum, sesbania gum, carrageenan, xanthan gum, konjac gum, sodium alginate, gelatin, agar, acrylic polymer and polyvinyl alcohol.
The organic solvent of the present invention is preferably acetone.
The method of the invention comprises the following steps:
(1) Taking a certain amount of the colloid propellant, and weighing the mass of the colloid propellant;
(2) Adding the organic solvent to the colloid propellant to precipitate the gelling agent;
(3) Separating the separated gelling agent from the liquid component;
(4) Washing the separated gelling agent;
(5) Drying the washed gelling agent;
(6) And weighing the dried gelling agent, and calculating the content of the gelling agent in the colloid propellant.
The dosage of the organic solvent is 1-100 mL of the organic solvent added to each gram of the colloid propellant, preferably 2-10 mL of the organic solvent added to each gram of the colloid propellant.
When the organic solvent is added to the colloidal propellant, a certain amount of water may also be incorporated into the organic solvent, and the amount of incorporated water does not affect the complete precipitation of the gelling agent.
Before the organic solvent is added into the colloid propellant, the volatile components in the colloid propellant can be completely or partially removed, so that the colloid propellant is concentrated.
The method for analyzing the content of the gelatinizer in the colloid propellant provided by the invention utilizes the characteristic that the gelatinizer is insoluble in a specific organic solvent to separate out and separate the gelatinizer, and simultaneously utilizes the reaction between the organic solvent and other components in the colloid propellant to ensure that all other components except the gelatinizer in a sample are soluble in the added organic solvent, so that the influence of the separation of other components along with the gelatinizer on the measurement of the content of the gelatinizer is avoided. Compared with the prior art, the method provided by the invention can be suitable for the analysis of colloid propellants with more types and more complex compositions, and particularly overcomes the defects of the prior art in the analysis of the content of the gelling agent of the salt-containing colloid propellants.
Detailed Description
In order to make the purposes, technical solutions and advantages of the embodiments of the present invention more clear, the following description of the technical solutions of the embodiments of the present invention will be made clearly and completely. It will be apparent that the described embodiments are some, but not all, embodiments of the invention. All other embodiments, which can be made by a person skilled in the art without creative efforts, based on the described embodiments of the present invention fall within the protection scope of the present invention.
The embodiment of the invention provides a method for analyzing the content of a gelatinizing agent in a colloid propellant. The method is applicable to colloid propellant which contains liquid propellant and gelatinizer. Wherein the liquid propellant contains one or more of hydrazine, hydrazine derivative with amino group (such as methyl hydrazine, and metadimethylhydrazine), hydroxylamine, and/or one or more of nitrate, hydrochloride, sulfate, phosphate, acetate, formate, and oxalate of the above materials. For example, the liquid propellant is pure methyl hydrazine, hydrazine-ethanol mixture, aqueous hydroxylamine nitrate solution, hydroxylamine nitrate-hydrazine-water mixture, etc.
The organic solvent used in the embodiment of the invention contains aldehyde compounds, ketone compounds or both aldehyde compounds and ketone compounds. For example, the organic solvent is pure acetone, an acetone-methanol mixed solvent, an acetaldehyde-ethyl acetate solution, a cyclohexanone-butyraldehyde-isopropanol solution, or the like.
The organic solvent used in the embodiments of the present invention may react with all or a portion of the other components of the colloidal propellant except the gelling agent, and the reaction products may be soluble in the organic solvent used. In the analysis of colloidal propellants comprising hydrazine salts, hydrazine derivative salts with amino groups, hydroxylamine salts, these salts cannot be dissolved in organic solvents by physical dissolution, but can be converted into organic solvent-soluble substances by reaction between the selected organic solvents and these salts. For example, when pure acetone is used as the organic solvent, the acetone may react with hydrazine, hydrazine derivatives having an amino group, hydroxylamine and salts of the above materials in the colloidal propellant according to the following formula:
a in the formula - And HA is an acid radical ion salified with hydrazine, hydrazine derivatives, hydroxylamine, and the corresponding acids thereof, respectively. The hydrazone, oxime, water and acid (i.e., HA in the formula) produced by the reaction are all soluble in acetone.
In at least one embodiment of the present invention, the colloidal propellant has other components besides the gelling agent that are not reactive with the organic solvent used, and these components are also soluble in the organic solvent used. For example, acetone is added to a colloidal propellant consisting of hydroxylamine nitrate-isopropyl alcohol-water-gelling agent, in which isopropyl alcohol and water do not react with acetone, but are both soluble in acetone.
Thus, in embodiments of the present invention, the colloidal propellant is added with sufficient organic solvent to provide a mixed system in which the components other than the gellant are present in liquid/solution form.
The gelling agent contained in the colloidal propellant in the examples of the present invention is separated out by itself because it is insoluble in the organic solvent to be added. Since only the gelling agent is precipitated alone in the mixed system, the gelling agent can be separated from the liquid/solution components in the mixed system by means of solid-liquid separation. The content of the separated gelatinizer in the colloid propellant can be calculated by weighing after other components attached to the gelatinizer are removed by washing and drying. For example, if acetone is added into the gel propellant composed of hydrazine-water-konjak gum in a sufficient amount, only the gelatinizer konjak gum is precipitated in the form of flocculent precipitate, and the gel propellant can be obtained by filtering, washing, drying and weighing the gel propellant to calculate the content of the gel propellant.
The gelling agent in at least one embodiment of the present invention is a high molecular gelling agent, and the high molecular gelling agent is one or more selected from cellulose derivatives, dextran, glucomannan, chitosan, starch, dextrin, guar gum, sesbania gum, carrageenan, xanthan gum, konjac gum, sodium alginate, gelatin, agar, acrylic polymers, and polyvinyl alcohol, for example, the gelling agent is cellulose sulfate, polyacrylamide, konjac gum-carrageenan mixture, and the like.
The organic solvent used in at least one embodiment of the present invention is preferably acetone. Among all aldehydes and ketones, acetone has a relatively small molecular weight, and a unit mass of acetone can react with a relatively large number of colloidal propellant samples; on the other hand, the acetone has proper polarity, and can be used as a weak-polarity organic solvent, so that the acetone can be mutually dissolved with solvents with stronger polarity such as common alcohol, water and the like in the propellant, and can avoid the gelling agent dissolved in the strong-polarity solvent from being dissolved in the solvent, thereby promoting the complete precipitation of the gelling agent.
In at least one embodiment of the present invention, the volume of organic solvent added per gram of colloidal propellant sample is between 1mL and 100mL, preferably between 2mL and 10mL. When the amount of the organic solvent to be added is too small, the organic solvent cannot completely react the components of the colloidal propellant which can react with the organic solvent (for example, 0.9mL of acetone is added to 1g of anhydrous hydrazine colloidal propellant, the added acetone can only react less than 40% of hydrazine, more hydrazine remains in the reaction system, the gelling agent which is soluble in hydrazine cannot be completely precipitated), or the components of the colloidal propellant which do not react with the organic solvent except the gelling agent still occupy a high proportion in the mixed system (for example, 0.8mL of organic solvent is added to 1g of colloidal propellant containing 50% by mass of water, the mass fraction of water in the obtained mixed system is not less than 30%, and the gelling agent which is easily soluble in water cannot be completely precipitated), thereby affecting the complete precipitation of the gelling agent. When the organic solvent is excessively added, the mass of the sample which can be analyzed is small in a reaction vessel with a certain capacity, the accuracy of the analysis of the content of the gelatinizer is affected (for example, the density of the colloid propellant is 1g/mL, the mass of the sample which can be analyzed at most once is 5g if 5mL of the organic solvent is added to each gram of sample in a vessel with a capacity of 30mL, the mass of the sample which can be analyzed at most once is only 0.2g if 149mL of the organic solvent is added to each gram of sample, the accuracy of a balance for weighing the content of the gelatinizer is limited, and the accuracy of the measurement result of the latter is far worse than the former), and unnecessary waste of the organic solvent is caused.
In at least one embodiment of the present invention, when an organic solvent is added to the colloidal propellant, a certain amount of water may be further added to the organic solvent. The polarity of the organic solvent can be properly improved by adding a small amount of water into the organic solvent, so that the solubility of the organic solvent to the strong polar components in the reaction system is enhanced. However, the amount of incorporated water should not be excessive to avoid partial or complete dissolution of the gellant therein, resulting in a gellant content measurement below its true value. For example, when a colloidal propellant containing a small amount of ammonium nitrate together with polyacrylamide as a gelling agent is analyzed, it is possible to treat it with an acetone-water (volume ratio of 90:10) mixed solvent, thereby completely precipitating polyacrylamide while ensuring that ammonium nitrate is not precipitated.
In at least one embodiment of the present invention, the volatile components in the colloidal propellant are removed completely or partially before the organic solvent is added to the colloidal propellant, so as to achieve concentration of the colloidal propellant, thereby reducing the amount of the organic solvent used. For example, when the colloidal propellant composed of the unsymmetrical dimethylhydrazine-water-gelling agent is analyzed, dry nitrogen is used for blowing the surface of the colloidal propellant in advance, so that part of unsymmetrical dimethylhydrazine in the colloidal propellant is volatilized and removed, and the amount of organic solvent required in the reaction is reduced.
The technical scheme of the present invention is further illustrated by the following specific examples, but the scope of the present invention is not limited by the specific conditions of these specific examples.
Example 1:
the colloidal hydrazine-70 propellant (hydrazine-70 consists of hydrazine and water, the gelling agent used is konjac gum) was taken in a 50mL centrifuge tube and the sample was weighed to have a net mass of 3.0134g. 30mL of acetone is added into a centrifuge tube, the gel agent konjak gum in the colloidal hydrazine-70 propellant is separated out in the acetone, the hydrazine reacts with the acetone, and the acetone, the nitrogen and the water which are reaction products and the water contained in the colloidal hydrazine-70 are all soluble in the acetone. The supernatant was removed by centrifugation, after which 20mL of acetone was added to the centrifuge tube and the solids of the gelling agent in the centrifuge tube were washed by shaking. Repeating the steps twice to completely clean impurities adsorbed on the surface of the gelatinizer. After the washing solvent was removed by centrifugation, the centrifuge tube was dried in an oven at 60 ℃ to constant weight, and the mass of the gelling agent was 0.0314g, and the mass fraction of the gelling agent in the sample was 0.0314 ≡ 3.0134 ×100% =1.04%.
Example 2:
the colloidal hydroxylamine nitrate propellant (consisting of hydroxylamine nitrate, isopropanol and water, the gelling agent used being polyvinyl alcohol) was taken in a 50mL centrifuge tube and the net mass of the sample was 4.1621g. The centrifuge tube was placed in a 60 ℃ water bath and the sample surface was purged with dry nitrogen to volatilize the volatile components of the sample to concentrate the sample. After nitrogen blowing for about 4 hours, the mass of the sample left was about 1/3 of the mass of the original sample. After stopping the concentration and cooling the sample to room temperature by standing, 13.5mL of a mixed solvent of acetone and 1.5mL of water was added thereto. The polyvinyl alcohol in the concentrated sample is separated out in the mixed solvent, and hydroxylamine nitrate reacts with acetone, and the reaction products of acetoxime, nitric acid, water and isopropanol and water contained in the sample are all soluble in the added mixed solvent. The supernatant was removed by centrifugation, a mixed solvent of 13.5mL of acetone and 1.5mL of water was added to the centrifuge tube, and the gelatinizer solid in the centrifuge tube was washed by shaking. Repeating the steps twice to completely clean impurities adsorbed on the surface of the gelatinizer. After centrifugation to remove the washing solvent, the centrifuge tube was placed in an oven at 60 ℃ and dried to constant weight, the mass of the gelling agent was weighed as 0.0932g, the mass fraction of the gelling agent in the sample was calculated to be 0.0932 +. 4.1621 ×100% = 2.24%.
Claims (9)
1. A method of analyzing the gellant content of a colloidal propellant, comprising:
the colloid propellant contains a liquid propellant and the gelling agent, wherein the liquid propellant contains one or more of hydrazine, hydrazine derivative with amino group and hydroxylamine, and/or one or more of nitrate, hydrochloride, sulfate, phosphate, acetate, formate and oxalate of the above substances;
adding an organic solvent into the colloid propellant, wherein the organic solvent contains aldehyde and/or ketone compounds;
the organic solvent may react with all or a portion of the other components of the colloidal propellant other than the gellant, the reaction product being soluble in the organic solvent, such as components of the colloidal propellant other than the gellant that are not reactive with the organic solvent, and the components may be soluble in the organic solvent;
the gelling agent in the colloid propellant is separated out by itself because it is insoluble in the organic solvent, and the content of the gelling agent in the colloid propellant is calculated by weighing after separating it.
2. The method of claim 1, wherein the gelling agent is a polymeric gelling agent.
3. The method according to claim 2, wherein the high molecular gelling agent is one or more selected from cellulose derivatives, dextran, glucomannan, chitosan, starch, dextrin, guar gum, sesbania gum, carrageenan, xanthan gum, konjac gum, sodium alginate, gelatin, agar, acrylic polymers, and polyvinyl alcohol.
4. The method according to claim 1, characterized in that the organic solvent is preferably acetone.
5. The method according to claim 1, characterized in that the method comprises the steps of:
(1) Taking a certain amount of the colloid propellant, and weighing the mass of the colloid propellant;
(2) Adding the organic solvent to the colloid propellant to precipitate the gelling agent;
(3) Separating the separated gelling agent from the liquid component;
(4) Washing the separated gelling agent;
(5) Drying the washed gelling agent;
(6) And weighing the dried gelling agent, and calculating the content of the gelling agent in the colloid propellant.
6. The method according to claim 1 or 5, characterized in that the volume of the organic solvent added per gram of the colloidal propellant is 1mL-100mL.
7. The method according to claim 6, characterized in that the volume of the organic solvent added per gram of the colloidal propellant is preferably 2mL-10mL.
8. The method according to claim 1 or 5, characterized in that when adding the organic solvent to the colloidal propellant, a certain amount of water is also incorporated into the organic solvent, and the amount of incorporated water does not affect the complete precipitation of the gelling agent.
9. The method of claim 1 or 5, wherein the concentration of the colloidal propellant is achieved by completely or partially removing volatile components from the colloidal propellant prior to adding the organic solvent to the colloidal propellant.
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| JP2004035947A (en) * | 2002-07-03 | 2004-02-05 | Shikoku Res Inst Inc | Anticorrosive coating material for aerosol spray can and ordinary simple repair method using the same |
| CN102519826A (en) * | 2011-12-20 | 2012-06-27 | 中国兵器工业第五九研究所 | Method for testing and evaluating gel content in hydroxyl-terminated polybutadiene propellant |
| GB201305590D0 (en) * | 2013-03-27 | 2013-05-08 | Bae Systems Plc | Non-phthalate propellants |
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| US6896751B2 (en) * | 2003-05-16 | 2005-05-24 | Universal Propulsion Company, Inc. | Energetics binder of fluoroelastomer or other latex |
| CN107941655B (en) * | 2017-11-10 | 2020-02-21 | 西安航天动力试验技术研究所 | Formula and preparation method of gel simulation liquid of rocket engine hydrazine gel propellant |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| JP2004035947A (en) * | 2002-07-03 | 2004-02-05 | Shikoku Res Inst Inc | Anticorrosive coating material for aerosol spray can and ordinary simple repair method using the same |
| CN102519826A (en) * | 2011-12-20 | 2012-06-27 | 中国兵器工业第五九研究所 | Method for testing and evaluating gel content in hydroxyl-terminated polybutadiene propellant |
| GB201305590D0 (en) * | 2013-03-27 | 2013-05-08 | Bae Systems Plc | Non-phthalate propellants |
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