NL2030955B1 - Method for extracting fulvic acid from diatomite - Google Patents
Method for extracting fulvic acid from diatomite Download PDFInfo
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- NL2030955B1 NL2030955B1 NL2030955A NL2030955A NL2030955B1 NL 2030955 B1 NL2030955 B1 NL 2030955B1 NL 2030955 A NL2030955 A NL 2030955A NL 2030955 A NL2030955 A NL 2030955A NL 2030955 B1 NL2030955 B1 NL 2030955B1
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- Prior art keywords
- diatomite
- extraction
- fulvic acid
- acid
- filtrate
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- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 title claims abstract description 63
- FCYKAQOGGFGCMD-UHFFFAOYSA-N Fulvic acid Natural products O1C2=CC(O)=C(O)C(C(O)=O)=C2C(=O)C2=C1CC(C)(O)OC2 FCYKAQOGGFGCMD-UHFFFAOYSA-N 0.000 title claims abstract description 47
- 239000002509 fulvic acid Substances 0.000 title claims abstract description 47
- 229940095100 fulvic acid Drugs 0.000 title claims abstract description 46
- PUKLDDOGISCFCP-JSQCKWNTSA-N 21-Deoxycortisone Chemical compound C1CC2=CC(=O)CC[C@]2(C)[C@@H]2[C@@H]1[C@@H]1CC[C@@](C(=O)C)(O)[C@@]1(C)CC2=O PUKLDDOGISCFCP-JSQCKWNTSA-N 0.000 title claims abstract description 45
- 238000000034 method Methods 0.000 title claims abstract description 22
- 238000000605 extraction Methods 0.000 claims abstract description 56
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 claims abstract description 9
- 238000004380 ashing Methods 0.000 claims abstract description 4
- 239000000706 filtrate Substances 0.000 claims description 13
- 239000000843 powder Substances 0.000 claims description 8
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Chemical compound O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 6
- 239000012153 distilled water Substances 0.000 claims description 5
- 238000001914 filtration Methods 0.000 claims description 5
- 239000007787 solid Substances 0.000 claims description 5
- 238000001035 drying Methods 0.000 claims description 2
- 238000001704 evaporation Methods 0.000 claims description 2
- 230000008020 evaporation Effects 0.000 claims description 2
- 238000005469 granulation Methods 0.000 claims description 2
- 230000003179 granulation Effects 0.000 claims description 2
- 238000002156 mixing Methods 0.000 claims description 2
- 238000003756 stirring Methods 0.000 claims description 2
- 238000007873 sieving Methods 0.000 claims 1
- 239000002904 solvent Substances 0.000 abstract description 9
- 230000000694 effects Effects 0.000 abstract description 4
- 229910052500 inorganic mineral Inorganic materials 0.000 abstract description 4
- 239000011707 mineral Substances 0.000 abstract description 4
- 230000007613 environmental effect Effects 0.000 abstract description 3
- 239000000047 product Substances 0.000 abstract description 3
- 238000000926 separation method Methods 0.000 abstract description 2
- 239000006227 byproduct Substances 0.000 abstract 1
- 239000004021 humic acid Substances 0.000 description 8
- 239000000463 material Substances 0.000 description 8
- 239000002253 acid Substances 0.000 description 6
- 239000002994 raw material Substances 0.000 description 5
- 238000011161 development Methods 0.000 description 4
- 239000000126 substance Substances 0.000 description 4
- 238000004448 titration Methods 0.000 description 4
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 3
- 241000196324 Embryophyta Species 0.000 description 3
- 229910052799 carbon Inorganic materials 0.000 description 3
- 239000012141 concentrate Substances 0.000 description 3
- 230000005684 electric field Effects 0.000 description 3
- 238000000874 microwave-assisted extraction Methods 0.000 description 3
- 235000010755 mineral Nutrition 0.000 description 3
- QJZYHAIUNVAGQP-UHFFFAOYSA-N 3-nitrobicyclo[2.2.1]hept-5-ene-2,3-dicarboxylic acid Chemical compound C1C2C=CC1C(C(=O)O)C2(C(O)=O)[N+]([O-])=O QJZYHAIUNVAGQP-UHFFFAOYSA-N 0.000 description 2
- CSCPPACGZOOCGX-UHFFFAOYSA-N Acetone Chemical compound CC(C)=O CSCPPACGZOOCGX-UHFFFAOYSA-N 0.000 description 2
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 2
- 150000007513 acids Chemical class 0.000 description 2
- 239000002585 base Substances 0.000 description 2
- 239000000306 component Substances 0.000 description 2
- 238000010438 heat treatment Methods 0.000 description 2
- 150000002500 ions Chemical class 0.000 description 2
- 239000003960 organic solvent Substances 0.000 description 2
- KMUONIBRACKNSN-UHFFFAOYSA-N potassium dichromate Chemical compound [K+].[K+].[O-][Cr](=O)(=O)O[Cr]([O-])(=O)=O KMUONIBRACKNSN-UHFFFAOYSA-N 0.000 description 2
- 238000007670 refining Methods 0.000 description 2
- 238000012216 screening Methods 0.000 description 2
- 238000011282 treatment Methods 0.000 description 2
- 208000035240 Disease Resistance Diseases 0.000 description 1
- 238000009825 accumulation Methods 0.000 description 1
- 238000012271 agricultural production Methods 0.000 description 1
- 239000003513 alkali Substances 0.000 description 1
- 238000003556 assay Methods 0.000 description 1
- 239000012752 auxiliary agent Substances 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000004071 biological effect Effects 0.000 description 1
- 238000009835 boiling Methods 0.000 description 1
- 150000001720 carbohydrates Chemical class 0.000 description 1
- 235000014633 carbohydrates Nutrition 0.000 description 1
- 239000003054 catalyst Substances 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 238000003776 cleavage reaction Methods 0.000 description 1
- 239000003086 colorant Substances 0.000 description 1
- 230000003750 conditioning effect Effects 0.000 description 1
- 239000003814 drug Substances 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 239000011790 ferrous sulphate Substances 0.000 description 1
- 235000003891 ferrous sulphate Nutrition 0.000 description 1
- 235000013305 food Nutrition 0.000 description 1
- 238000007710 freezing Methods 0.000 description 1
- 230000008014 freezing Effects 0.000 description 1
- 239000012767 functional filler Substances 0.000 description 1
- 239000005556 hormone Substances 0.000 description 1
- 229940088597 hormone Drugs 0.000 description 1
- 239000003906 humectant Substances 0.000 description 1
- 229910052739 hydrogen Inorganic materials 0.000 description 1
- 239000001257 hydrogen Substances 0.000 description 1
- 230000003301 hydrolyzing effect Effects 0.000 description 1
- 238000009776 industrial production Methods 0.000 description 1
- 239000002917 insecticide Substances 0.000 description 1
- 239000012774 insulation material Substances 0.000 description 1
- 230000009878 intermolecular interaction Effects 0.000 description 1
- BAUYGSIQEAFULO-UHFFFAOYSA-L iron(2+) sulfate (anhydrous) Chemical compound [Fe+2].[O-]S([O-])(=O)=O BAUYGSIQEAFULO-UHFFFAOYSA-L 0.000 description 1
- 229910000359 iron(II) sulfate Inorganic materials 0.000 description 1
- 230000001678 irradiating effect Effects 0.000 description 1
- 238000013332 literature search Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 239000011159 matrix material Substances 0.000 description 1
- 239000012229 microporous material Substances 0.000 description 1
- 150000007522 mineralic acids Chemical class 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 239000005416 organic matter Substances 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 230000035515 penetration Effects 0.000 description 1
- 230000029553 photosynthesis Effects 0.000 description 1
- 238000010672 photosynthesis Methods 0.000 description 1
- 239000011148 porous material Substances 0.000 description 1
- 238000000746 purification Methods 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 230000007017 scission Effects 0.000 description 1
- 239000002689 soil Substances 0.000 description 1
- 238000001179 sorption measurement Methods 0.000 description 1
- 230000005068 transpiration Effects 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07G—COMPOUNDS OF UNKNOWN CONSTITUTION
- C07G99/00—Subject matter not provided for in other groups of this subclass
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Extraction Or Liquid Replacement (AREA)
Abstract
The present disclosure relates to a method for extracting fulvic acid from diatomite and belongs to the technical field of comprehensive utilization of mineral resources. The method is directed to extract fulvic acid from crushed diatomite with uses sulfuric acid as a solvent under microwave irradiation and then obtain main product active diatomite and by—product fulvic acid by separation. The method, is simple and feasible and can greatly lessen the environmental problems caused by burning and ashing of refined diatomite. Moreover, the method effectively increases the extraction rate of fulvic acid without affecting the activity and structure of diatomite.
Description
P1109/NLpd
METHOD FOR EXTRACTING FULVIC ACID FROM DIATOMITE
The present disclosure relates to a method for extracting fulvic acid from diatomite, in particular to a microwave-assisted method for extracting fulvic acid from diatomite to refine diato- mite, and belongs to the technical field of comprehensive utiliza- tion of mineral resources.
Diatomite mineral resources are rich and widely distributed around the world. Diatomite is characterized by fine texture, light weight, porousness, acid and alkali resistance, etc. Diato- mite has been widely used as a filter aid, a thermal insulation material, a catalyst carrier and the like. With the development of modern technology and the deepening of study on the properties of diatomite, diatomite is further used as a high-quality filter aid, a microporous material, a functional filler, an insecticide, a soil conditioning humectant, etc.
The Xianfeng diatomite deposit in Yunnan has huge geological reserves and is the second largest deposit in China, and its diat- omite contains about 17% to 32% of humic acids. Humic acids are highly complex in composition and mainly composed of fulvic acid, ulmic acid, and black humic acid. The three types of substances have increasing molecular weights, and their colors deepen one by one, but there is no clear-cut distinction among them. Among such substances, one with the smaller molecular weight is called fulvic acid (FA), with a molecular weight ranging from 300 to 600. Fulvic acid is soluble in water, acids, bases, and organic solvents such as acetone and ethanol, and has high application value. Fulvic ac- id exhibits some higher biological activities than other compo- nents of humic acids and has a similar structure to six major bio- logical hormones currently found in the world. These properties make fulvic acid widely used in modern agriculture. Production practice and scientific research have shown that fulvic acid is able to promote the development of plant roots, improve the vital- ity of plant roots, and reduce the opening of plant leaf stomas to lower transpiration, and can improve the drought resistance of crops and thus has been widely used in agricultural production as a drought resistant agent. In addition, fulvic acid can also im- prove the disease resistance and freezing resistance of crops, promote photosynthesis, increase the activity of a variety of en- zymes, and promote the accumulation of sugar and dry matter. The agricultural use of fulvic acid can effectively improve the yield and quality of crops. Furthermore, fulvic acid has broad applica- tion prospects in industrial production such as medicine and food safety. For a long time, the development and utilization of diato- mite are limited to the purification and refining of active Si02.
Humic acids are usually ashed, and the utilization of the valuable resources such as fulvic acid is neglected. Theoretically, any minerals that are rich in organic matter such as humic acids can be used as raw materials for extraction of fulvic acid. Xianfeng diatomite is a typical diatomite with high burning loss and has a relatively high content of organic components. The carbon ratio of fulvic acid in this diatomite is measured to be about 0.41, indi- cating that extraction of fulvic acid from this diatomite has practical development and utilization value.
Studies have shown that under a pH of 1 to 1.5, fulvic acid can be dissolved in an acid solvent, while ulmic acid and black humic acid cannot be dissolved. Therefore, acids are preferred to be used in the extraction and separation of fulvic acid. However, due to the good adsorption activity of diatomite, experiments have proved that the extraction rate of fulvic acid from the diatomite with an inorganic acid as a solvent is low. The use of an inorgan- ic solvent as an auxiliary agent will not only pollute the diato- mite to a certain extent, but also cause environmental problems.
Besides, the treatment of diatomite with a base will destroy the structure of the diatomite and affect the structure and perfor- mance of the diatomite product.
When microwaves are used as a heat source, the heating effect of the microwaves is manifested in the conversion of electromag- netic energy into heat energy by irradiating electromagnetic waves onto a polar dielectric. This process is largely related to the polarity of a material. A polar material is composed of polar mol- ecules, and the positive and negative charge centers of such polar molecules do not overlap. It can be regarded as particles with different charges being gathered at both ends, and this polar ma- terial may be called a dipole. In the natural environment, the ar- rangement of the molecules of a material is disordered, and in the microwave environment, this arrangement is changed to a regular arrangement, for example, the regular arrangement of a dipole ori- ented in an electric field direction. Under the action of the al- ternating current, the electric field direction changes at a high frequency, causing a dipole located therein to rotate at a high speed. The interference and hindrance of the intermolecular inter- action force during the motion may be similar to internal fric- tion. Through this process, the electric field energy absorbed by the dielectric can be converted into heat energy, causing the tem- perature of the dielectric to increase accordingly.
After literature search, it is found that there is no report about a microwave-assisted extraction method for extracting fulvic acid from diatomite and refining diatomite.
An objective of the present disclosure is to provide a method for extracting fulvic acid from diatomite, specifically including the following steps: (1) crushing and screening diatomite ore to obtain a diato- mite ore powder with less than 5% of residue on an 80-mesh sieve; (2) adding the diatomite ore powder to distilled water, stir- ring and mixing fully, and then adding concentrated sulfuric acid to adjust a pH to a range of 1 to 1.5, with a liquid-to-solid ra- tio of 15-20 ml/g; and (3) after extraction for 1-3 times under microwave irradia- tion, filtering to obtain a filtrate and filter residue, subject- ing the filtrate to evaporation and granulation to obtain fulvic acid, drying and ashing the filter residue to obtain refined diat- omite.
The extraction is carried out under the following conditions:
an extraction pressure of 0.5-0.7 MPa, an extraction temperature of 110-140°C, each duration of extraction of 6-8 minutes, and a pH of 1-2 maintained during the extraction.
Since the internal pressure of a microwave airtight container used in this method can be 1 MPa or above, the boiling point of a solvent is much higher than that of the solvent under normal pres- sure. The microwave-assisted extraction method can provide a high extraction temperature. Microwave is a high-frequency wave which has high heating efficiency. Under the action of microwave irradi- ation, positive and negative poles formed by polar molecules in diatomite and the solvent change at a rate of billions of times per second, which induces dipole vortex, ion conduction and high- frequency friction and thus generates great heat in a very short time. In addition, the accelerated rotation and thermodynamic ef- fects of dipole molecules may cause hydrolytic cleavage of weak chemical bonds (such as -0-) or hydrogen bonds in humic acids and carbohydrates in the pores of diatomite, and intensified ion mi- gration, thereby accelerating the penetration of solvent molecules into a sample matrix and making the substance to be extracted en- ter into the solvent more easily.
The present disclosure has the following beneficial effects. (1) By the method of the present disclosure, the extraction rate of fulvic acid is 30-35%, and no damage is caused to the ac- tivity and structure of diatomite. Besides, no organic solvent is used, thereby avoiding pollution to the environment and the diato- mite. (2) First, using microwaves as a heat source, the utilization rate of energy can be effectively increased. Second, after one or more microwave-assisted extraction treatments, the valuable re- source fulvic acid can be well separated and recovered. This meth- od shows an extraction rate 2-3 times higher than that in extrac- tion with only sulfuric acid. The raw material pretreatment is simplified, and the operation time is effectively shortened. (3) The treated diatomite is not polluted with maintained ac- tivity and structure and thus can be refined into a diatomite product having excellent properties. Thus, rational utilization of diatomite resources is effectively realized. In addition, micro-
wave-assisted extraction can also greatly lessen a series of envi- ronmental problems caused by exhaust emission in a process for re- fining diatomite by burning and ashing. 5 BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a flowchart of a method for extracting fulvic acid from diatomite according to the present disclosure.
The present disclosure will be further described below in de- tail in conjunction with the accompanying drawings and specific examples. However, the protection scope of the present disclosure is not limited to the following description.
The raw material used in Examples 1 to 3 was pretreated as follows: (1) The raw material diatomite was crushed and passed through a coarse sieve. The oversize material was crushed again, while the undersize material was pulverized in a pulverizer and then screened through an 80-mesh fine sieve. The oversize material, namely diatomite of more than 80 meshes, was pulverized again, while the undersize material was subjected to the next process. (2) Using potassium dichromate and ferrous sulfate, titration assay was conducted on the undersize material obtained by screen- ing through the 80-mesh fine sieve in step (1), namely diatomite powder of less than 80 meshes, and a carbon ratio of fulvic acid in the raw material diatomite was measured by using a gravimetric method. The measured carbon ratio of fulvic acids in this batch of diatomite was 0.41.
Example 1 (1) 50g of diatomite ore powder was added to distilled water, fully stirred and mixed, and then concentrated sulfuric acid was added to adjust the pH to 1, with a liquid-to-solid ratio of 20 ml/g. (2) Extraction was carried out once under microwave irradia- tion (the conditions during the extraction were as follows: an ex- traction pressure of 0.5 MPa, an extraction temperature of 110°C, each duration of extraction of 6 minutes, and the pH of 1-2 main-
tained during the extraction), followed by filtering to obtain a filtrate and filter residue. The filtrate was evaporated and gran- ulated to obtain fulvic acid, and the filter residue was dried and ashed to obtain refined diatomite.
The extraction rate of fulvic acid was measured by the fol- lowing steps: after the completion of extraction in an extraction pot, allow the extraction pot to stand, pour upper cerise red so- lution into a centrifuge tube, centrifuge at 2000 r/min for 10 minutes, concentrate the filtrate by using a rotary evaporator to 100 ml, measure the extraction amount of fulvic acid by titration, and calculate the extraction rate of fulvic acid, which was 30.89%.
Example 2 (1) 50g of diatomite ore powder was added to distilled water, fully stirred and mixed, and then concentrated sulfuric acid was added to adjust the pH to 1.2, with a liquid-to-solid ratio of 17 ml/g. (2) Extraction was carried out twice under microwave irradia- tion (the conditions during the extraction were as follows: an ex- traction pressure of 0.6 MPa, an extraction temperature of 130°C, each duration of extraction of 7 minutes, and the pH of 1-2 main- tained during the extraction), followed by filtering to obtain a filtrate and filter residue. The filtrate was evaporated and gran- ulated to obtain fulvic acid, and the filter residue was dried and ashed to obtain refined diatomite.
The extraction rate of fulvic acid was measured by the fol- lowing steps: after the completion of extraction in an extraction pot, allow the extraction pot to stand, pour upper cerise red so- lution into a centrifuge tube, centrifuge at 2000 r/min for 10 minutes, concentrate the filtrate by using a rotary evaporator to 100 ml, measure the extraction amount of fulvic acid by titration, and calculate the extraction rate of fulvic acid, which was 31.15%.
Example 3 (1) 50g of diatomite ore powder was added to distilled water, fully stirred and mixed, and then concentrated sulfuric acid was added to adjust the pH to 1.5, with a liquid-to-solid ratio of 15 ml/g. (2) Extraction was carried out for 3 times under microwave irradiation (the conditions during the extraction were as follows: an extraction pressure of 0.7 MPa, an extraction temperature of 140°C, each duration of extraction of 8 minutes, and the pH of 1-2 maintained during the extraction), followed by filtering to obtain a filtrate and filter residue. The filtrate was evaporated and granulated to obtain fulvic acid, and the filter residue was dried and ashed to obtain refined diatomite.
The extraction rate of fulvic acid was measured by the fol- lowing steps: after the completion of extraction in an extraction pot, allow the extraction pot to stand, pour upper cerise red so- lution into a centrifuge tube, centrifuge at 2000 r/min for 10 minutes, concentrate the filtrate by using a rotary evaporator to 100 ml, measure the extraction amount of fulvic acid by titration, and calculate the extraction rate of fulvic acid, which was 50%.
Claims (2)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| NL2030955A NL2030955B1 (en) | 2022-02-15 | 2022-02-15 | Method for extracting fulvic acid from diatomite |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| NL2030955A NL2030955B1 (en) | 2022-02-15 | 2022-02-15 | Method for extracting fulvic acid from diatomite |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| NL2030955B1 true NL2030955B1 (en) | 2023-08-21 |
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| NL2030955A NL2030955B1 (en) | 2022-02-15 | 2022-02-15 | Method for extracting fulvic acid from diatomite |
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| Country | Link |
|---|---|
| NL (1) | NL2030955B1 (en) |
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2022
- 2022-02-15 NL NL2030955A patent/NL2030955B1/en active
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