LU102511B1 - Grafting Type Starch Water Treatment Agent with Flocculation and Sterilization Functions As Well As Preparation Method Thereof - Google Patents
Grafting Type Starch Water Treatment Agent with Flocculation and Sterilization Functions As Well As Preparation Method Thereof Download PDFInfo
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- LU102511B1 LU102511B1 LU102511A LU102511A LU102511B1 LU 102511 B1 LU102511 B1 LU 102511B1 LU 102511 A LU102511 A LU 102511A LU 102511 A LU102511 A LU 102511A LU 102511 B1 LU102511 B1 LU 102511B1
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- starch
- water treatment
- treatment agent
- grafting
- flocculation
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- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 title claims abstract description 148
- 229920002472 Starch Polymers 0.000 title claims abstract description 126
- 239000008107 starch Substances 0.000 title claims abstract description 126
- 235000019698 starch Nutrition 0.000 title claims abstract description 126
- 239000003795 chemical substances by application Substances 0.000 title claims abstract description 97
- 238000004659 sterilization and disinfection Methods 0.000 title claims abstract description 56
- 230000001954 sterilising effect Effects 0.000 title claims abstract description 55
- 238000005189 flocculation Methods 0.000 title claims abstract description 54
- 230000016615 flocculation Effects 0.000 title claims abstract description 54
- 238000002360 preparation method Methods 0.000 title claims abstract description 19
- 229920006320 anionic starch Polymers 0.000 claims abstract description 55
- 229920002401 polyacrylamide Polymers 0.000 claims abstract description 38
- HRPVXLWXLXDGHG-UHFFFAOYSA-N Acrylamide Chemical compound NC(=O)C=C HRPVXLWXLXDGHG-UHFFFAOYSA-N 0.000 claims abstract description 16
- 238000006467 substitution reaction Methods 0.000 claims abstract description 14
- 125000000129 anionic group Chemical class 0.000 claims abstract description 12
- -1 cationic tertiary amine salt Chemical class 0.000 claims abstract description 12
- 238000006683 Mannich reaction Methods 0.000 claims abstract description 7
- 238000007334 copolymerization reaction Methods 0.000 claims abstract description 7
- WSFSSNUMVMOOMR-UHFFFAOYSA-N Formaldehyde Chemical compound O=C WSFSSNUMVMOOMR-UHFFFAOYSA-N 0.000 claims description 36
- CSCPPACGZOOCGX-UHFFFAOYSA-N Acetone Chemical compound CC(C)=O CSCPPACGZOOCGX-UHFFFAOYSA-N 0.000 claims description 24
- ROSDSFDQCJNGOL-UHFFFAOYSA-N Dimethylamine Chemical compound CNC ROSDSFDQCJNGOL-UHFFFAOYSA-N 0.000 claims description 22
- FOCAUTSVDIKZOP-UHFFFAOYSA-N chloroacetic acid Chemical compound OC(=O)CCl FOCAUTSVDIKZOP-UHFFFAOYSA-N 0.000 claims description 17
- 229940106681 chloroacetic acid Drugs 0.000 claims description 17
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 claims description 15
- 238000006243 chemical reaction Methods 0.000 claims description 14
- KWYUFKZDYYNOTN-UHFFFAOYSA-M Potassium hydroxide Chemical compound [OH-].[K+] KWYUFKZDYYNOTN-UHFFFAOYSA-M 0.000 claims description 12
- 239000003999 initiator Substances 0.000 claims description 12
- 239000012716 precipitator Substances 0.000 claims description 12
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 claims description 10
- ROOXNKNUYICQNP-UHFFFAOYSA-N ammonium persulfate Chemical compound [NH4+].[NH4+].[O-]S(=O)(=O)OOS([O-])(=O)=O ROOXNKNUYICQNP-UHFFFAOYSA-N 0.000 claims description 10
- 239000003513 alkali Substances 0.000 claims description 9
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 claims description 8
- 239000007789 gas Substances 0.000 claims description 8
- USHAGKDGDHPEEY-UHFFFAOYSA-L potassium persulfate Chemical compound [K+].[K+].[O-]S(=O)(=O)OOS([O-])(=O)=O USHAGKDGDHPEEY-UHFFFAOYSA-L 0.000 claims description 7
- XMPZTFVPEKAKFH-UHFFFAOYSA-P ceric ammonium nitrate Chemical group [NH4+].[NH4+].[Ce+4].[O-][N+]([O-])=O.[O-][N+]([O-])=O.[O-][N+]([O-])=O.[O-][N+]([O-])=O.[O-][N+]([O-])=O.[O-][N+]([O-])=O XMPZTFVPEKAKFH-UHFFFAOYSA-P 0.000 claims description 6
- 238000006266 etherification reaction Methods 0.000 claims description 6
- 238000001914 filtration Methods 0.000 claims description 6
- 239000011261 inert gas Substances 0.000 claims description 6
- 239000000203 mixture Substances 0.000 claims description 6
- 229910001870 ammonium persulfate Inorganic materials 0.000 claims description 5
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 claims description 4
- 229910052786 argon Inorganic materials 0.000 claims description 4
- 229910001873 dinitrogen Inorganic materials 0.000 claims description 4
- 229910052754 neon Inorganic materials 0.000 claims description 4
- GKAOGPIIYCISHV-UHFFFAOYSA-N neon atom Chemical compound [Ne] GKAOGPIIYCISHV-UHFFFAOYSA-N 0.000 claims description 4
- 244000046052 Phaseolus vulgaris Species 0.000 claims description 3
- 235000010627 Phaseolus vulgaris Nutrition 0.000 claims description 3
- 235000013339 cereals Nutrition 0.000 claims description 3
- 229920001592 potato starch Polymers 0.000 claims description 3
- 230000035484 reaction time Effects 0.000 claims description 3
- 239000000243 solution Substances 0.000 description 22
- 239000000047 product Substances 0.000 description 17
- 230000000694 effects Effects 0.000 description 14
- 239000000463 material Substances 0.000 description 14
- 239000000725 suspension Substances 0.000 description 14
- 229920005615 natural polymer Polymers 0.000 description 12
- 125000002091 cationic group Chemical group 0.000 description 10
- 238000000034 method Methods 0.000 description 9
- 239000005995 Aluminium silicate Substances 0.000 description 8
- 241000588724 Escherichia coli Species 0.000 description 8
- 235000012211 aluminium silicate Nutrition 0.000 description 8
- NLYAJNPCOHFWQQ-UHFFFAOYSA-N kaolin Chemical compound O.O.O=[Al]O[Si](=O)O[Si](=O)O[Al]=O NLYAJNPCOHFWQQ-UHFFFAOYSA-N 0.000 description 8
- 150000001768 cations Chemical class 0.000 description 6
- 239000003651 drinking water Substances 0.000 description 6
- 235000020188 drinking water Nutrition 0.000 description 6
- 239000008394 flocculating agent Substances 0.000 description 6
- 239000002861 polymer material Substances 0.000 description 6
- 239000000126 substance Substances 0.000 description 6
- 241000894006 Bacteria Species 0.000 description 5
- 231100000252 nontoxic Toxicity 0.000 description 5
- 230000003000 nontoxic effect Effects 0.000 description 5
- 229920000642 polymer Polymers 0.000 description 5
- 238000011161 development Methods 0.000 description 4
- 238000010586 diagram Methods 0.000 description 4
- 230000002378 acidificating effect Effects 0.000 description 3
- 229910052782 aluminium Inorganic materials 0.000 description 3
- 230000007547 defect Effects 0.000 description 3
- 230000003311 flocculating effect Effects 0.000 description 3
- 230000005764 inhibitory process Effects 0.000 description 3
- 150000003839 salts Chemical class 0.000 description 3
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 description 2
- ZAMOUSCENKQFHK-UHFFFAOYSA-N Chlorine atom Chemical compound [Cl] ZAMOUSCENKQFHK-UHFFFAOYSA-N 0.000 description 2
- 241000196324 Embryophyta Species 0.000 description 2
- 238000010521 absorption reaction Methods 0.000 description 2
- AZDRQVAHHNSJOQ-UHFFFAOYSA-N alumane Chemical class [AlH3] AZDRQVAHHNSJOQ-UHFFFAOYSA-N 0.000 description 2
- 239000006227 byproduct Substances 0.000 description 2
- 230000006378 damage Effects 0.000 description 2
- 230000000855 fungicidal effect Effects 0.000 description 2
- 239000000417 fungicide Substances 0.000 description 2
- 229910052736 halogen Inorganic materials 0.000 description 2
- 150000002367 halogens Chemical class 0.000 description 2
- 238000009776 industrial production Methods 0.000 description 2
- 238000002329 infrared spectrum Methods 0.000 description 2
- XEEYBQQBJWHFJM-UHFFFAOYSA-N iron Substances [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 2
- 229910052742 iron Inorganic materials 0.000 description 2
- 150000003242 quaternary ammonium salts Chemical group 0.000 description 2
- 238000011160 research Methods 0.000 description 2
- 208000024827 Alzheimer disease Diseases 0.000 description 1
- 229920002101 Chitin Polymers 0.000 description 1
- 229920002261 Corn starch Polymers 0.000 description 1
- 241001465754 Metazoa Species 0.000 description 1
- 229920000881 Modified starch Polymers 0.000 description 1
- 239000004368 Modified starch Substances 0.000 description 1
- 229920000615 alginic acid Polymers 0.000 description 1
- 239000000783 alginic acid Substances 0.000 description 1
- 235000010443 alginic acid Nutrition 0.000 description 1
- 229960001126 alginic acid Drugs 0.000 description 1
- 150000004781 alginic acids Chemical class 0.000 description 1
- 150000001408 amides Chemical class 0.000 description 1
- 230000000844 anti-bacterial effect Effects 0.000 description 1
- 239000007864 aqueous solution Substances 0.000 description 1
- 239000003899 bactericide agent Substances 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 239000001569 carbon dioxide Substances 0.000 description 1
- 229910002092 carbon dioxide Inorganic materials 0.000 description 1
- 229920002678 cellulose Polymers 0.000 description 1
- 239000001913 cellulose Substances 0.000 description 1
- 239000000701 coagulant Substances 0.000 description 1
- 239000008120 corn starch Substances 0.000 description 1
- 230000007797 corrosion Effects 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
- 230000001877 deodorizing effect Effects 0.000 description 1
- 230000008021 deposition Effects 0.000 description 1
- 239000010840 domestic wastewater Substances 0.000 description 1
- 239000003814 drug Substances 0.000 description 1
- 230000009977 dual effect Effects 0.000 description 1
- 238000009713 electroplating Methods 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 238000003912 environmental pollution Methods 0.000 description 1
- 239000003337 fertilizer Substances 0.000 description 1
- 239000012847 fine chemical Substances 0.000 description 1
- 235000013305 food Nutrition 0.000 description 1
- 239000003112 inhibitor Substances 0.000 description 1
- 230000002401 inhibitory effect Effects 0.000 description 1
- 150000002505 iron Chemical class 0.000 description 1
- 229920002521 macromolecule Polymers 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 229910021645 metal ion Inorganic materials 0.000 description 1
- 230000002906 microbiologic effect Effects 0.000 description 1
- 235000019426 modified starch Nutrition 0.000 description 1
- 239000000178 monomer Substances 0.000 description 1
- 229920000620 organic polymer Polymers 0.000 description 1
- 239000000575 pesticide Substances 0.000 description 1
- 239000003208 petroleum Substances 0.000 description 1
- 238000004537 pulping Methods 0.000 description 1
- 239000002994 raw material Substances 0.000 description 1
- 238000012827 research and development Methods 0.000 description 1
- 239000002455 scale inhibitor Substances 0.000 description 1
- 239000010865 sewage Substances 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 238000005728 strengthening Methods 0.000 description 1
- 229920005613 synthetic organic polymer Polymers 0.000 description 1
- 229920001059 synthetic polymer Polymers 0.000 description 1
- 125000001302 tertiary amino group Chemical group 0.000 description 1
- 231100000331 toxic Toxicity 0.000 description 1
- 230000002588 toxic effect Effects 0.000 description 1
- 238000004065 wastewater treatment Methods 0.000 description 1
- 229920003169 water-soluble polymer Polymers 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
- C08F251/00—Macromolecular compounds obtained by polymerising monomers on to polysaccharides or derivatives thereof
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/52—Treatment of water, waste water, or sewage by flocculation or precipitation of suspended impurities
- C02F1/54—Treatment of water, waste water, or sewage by flocculation or precipitation of suspended impurities using organic material
- C02F1/56—Macromolecular compounds
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/52—Treatment of water, waste water, or sewage by flocculation or precipitation of suspended impurities
- C02F1/5263—Treatment of water, waste water, or sewage by flocculation or precipitation of suspended impurities using natural chemical compounds
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F2303/00—Specific treatment goals
- C02F2303/04—Disinfection
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Health & Medical Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Medicinal Chemistry (AREA)
- Polymers & Plastics (AREA)
- Life Sciences & Earth Sciences (AREA)
- Hydrology & Water Resources (AREA)
- Engineering & Computer Science (AREA)
- Environmental & Geological Engineering (AREA)
- Water Supply & Treatment (AREA)
- Separation Of Suspended Particles By Flocculating Agents (AREA)
Abstract
The invention discloses a grafting type starch water treatment agent with flocculation and sterilization functions which is a grafting type amphoteric starch water treatment agent which is obtained by virtue of grafting copolymerization of anionic starch and acrylamide followed by Mannich reaction, a molecular formula of the grafting type starch water treatment agent with flocculation and sterilization functions is expressed as follows: R1: H $t CH2COO R2: NH2 $ NHCH2N(CH3)2 wherein in the grafting type amphoteric starch water treatment agent, a degree of substitution of anionic groups is 1-50%, a degree of substitution of cationic tertiary amine salt is 5-70%, and the polyacrylamide accounts for 5-80% of the grafting type amphoteric starch water treatment agent. The preparation method of the grafting type starch water treatment agent comprises the following steps: (1) preparing anionic starch; (2) preparing polyacrylamide grafting anionic starch; and (3) preparing grafting type amphoteric starch water treatment agent with flocculation and sterilization functions.
Description
DESCRIPTION Grafting Type Starch Water Treatment Agent with Flocculation and Sterilization Functions As Well As Preparation Method Thereof
TECHNICAL FIELD The invention relates to the field of organic polymers, in particular to a grafting type amphoteric starch water treatment agent with flocculation and sterilization functions as well as a preparation method thereof.
BACKGROUND In recent years, water, which is a basic need for people's life, has been polluted more and more seriously with rapid development of economy and industry. Having highly-valued safety guarantee of drinking water, China officially implements the newly revised “Sanitary Standard for Drinking Water” (GB 5749-2006) on July 1, 2007, ending the old standard (GB 5749-1985) that lasted for 21 years. Indexes stipulated in the new standard are significantly increased from the original 35 to 106, and limits of some indexes are also more stringent. In addition, China has successively released 18 new and more stringent industrial emission standards including pulping and papermaking, electroplating, chemical fertilizers and pesticides from 2008 to 2011, which have important practical significance for guaranteeing people's drinking water safety and improving people's life quality The water treatment agent, essential in conventional water treatment, is an important fine chemical product, which mainly can be used for removing suspended solids in water, deodorizing and discoloring, inhibiting bacteria,
sterilizing, softening water, reducing water scales, reducing damages, on equipment, of raw water, and the like. In accordance with its functional characteristics, the water treatment agent can be divided into coagulants/flocculants, bactericides, scale inhibitors, corrosion inhibitors, and the like for large-scale use, thereby providing a great deal of clean drinking water as well as industrial and agricultural water for people, greatly alleviating harm, on environment, of polluted water, and effectively maintaining balance of an ecologica! system. The water treatment agent plays an important role in purifying current industrial sewage and domestic wastewater. Various water treatment agents need to add for purifying water of complex conditions through multi-gear research practice, thus increasing operation difficulty, increasing production cost and easily causing mutual interference to affect treatment effect. Undoubtedly, it is one of the important directions that an efficient multifunctional water treatment agent is developed as a future novel water treatment agent material.
The multifunctional water treatment agent has two or more functions of fundamental flocculation, sterilization, scale inhibition and the like. An inorganic flocculant material, which is mainly an aluminum salt and an iron salt, is the most common flocculant for current water treatment because of its good flocculation effect and relatively low price. In use, this flocculant inevitably leads to residues, in water, of a trace amount of aluminum ions or iron ions due to its single function, thus increasing content of metal ions in water and harming people's health if people drink this water for a long time, for example Alzheimer's disease caused by deposition, in a human body, of aluminum ions. Residues of the aluminum ions and the iron ions have been clearly stipulated in the new standard.
In addition, synthetic organic polymer flocculants, such as polyacrylamide, are superior to inorganic flocculants in effect, are small in usage amount and are higher in price. It is generally accepted that aluminum salt and polyacrylamide should be used with caution in a water treatment process to purify water as monomers such as polyacrylamide that do not participate in reaction in the high polymer are highly toxic. This risk is reduced by greatly reducing a mass proportion, in the flocculant, of the added polyacrylamide even through the flocculant has a polyacrylamide chain section.
Natural polymers are macromolecules in animals, plants and microbiological resources in nature, such as starch, chitin, cellulose, and alginic acid, are easily decomposed into water, carbon dioxide, and the like after being discarded, are widely sourced, nontoxic and environment-friendly. In addition, it is worth mentioning that natural polymer materials are renewable resources that are completely separated from petroleum resources, which can be inexhaustible. With the above-mentioned excellent properties, the natural polymer materials have been widely used in many fields such as biology, medicine and food processing. In addition, natural polymers have good flocculation due to a large amount of free reactive groups distributed on the molecular chain, and have been used as water purifiers in ancient times. However, research on the natural polymers enters a stagnation period in recent years due to the rapid development of inorganic flocculants and synthetic polymer flocculants. In recent years, with the increasing environmental pollution, natural polymer materials have become one of the hotspots in the development of water treatment agents due to their environmental characteristics, and have been regarded as the best alternative materials for the current use of inorganic flocculants. Since the 1970s, countries such as Japan, the United States, the United Kingdom, and France have begun to use natural polymer water treatment agents in wastewater treatment. China, with extremely rich natural polymer resources, carry out few studies in this area, most of which are still in the laboratory and are scarcely applied in use, and carry out fewer research and development on multifunctional natural high polymer water treatment agents. Nowadays, the Chinese government attaches great importance to the quality of drinking water, and has announced and implemented new sanitary standards of drinking water and industrial emission standards, which undoubtedly provide a good opportunity for the further development of the natural polymer water treatment agents.
Where, starch is one of the natural polymer materials with superior performance, which widely exists in the seeds and tubers of various plants, with a structure as shown in Fig. 1.
OH OH H a
H H Formula 1 The starch molecular chain contains a large number of reactive groups -OH, showing good flocculation performance. In practical use, starch also has many defects such as no charge on starch molecules, inactive chemical properties, poor solubility, relatively low molecular weight and a narrow applicable PH range.
People use a chemical modifying method to improve the defects. Compared with other modified starch materials (such as non-grafted materials, anionic materials, cationic materials and the like), amphoteric starch is greatly improved in water solubility, is suitable for processing water with different charges because of having dual characteristics, has good salt resistance, is wide in range of application, and can be used in both an acidic medium and an alkali medium. Besides, other polymer chains, especially a water-soluble polymer chain, are grafted and introduced onto a starch molecule main chain from the bonding bridging principle in flocculation of the polymer flocculant, thereby improving molecular weight of the polymer,
. a . , | LU102511 strengthening bonding, bridging and flocculating effect, and further improving water solubility of starch.
At present, there are no grafting type starch water treatment agent with flocculation and sterilization functions that can both sterilize and flocculate as well as a preparation method thereof.
SUMMARY To overcome the defects in the prior art, an objective of the invention is to provide a grafting type amphoteric starch water treatment agent with flocculation and sterilization functions as well as a preparation method thereof.
To achieve the objective, the invention provides the following technical scheme: a grafting type amphoteric starch water treatment agent with flocculation and sterilization functions is provided, a grafting type amphoteric starch water treatment agent is obtained by virtue of grafting copolymerization of anionic starch and acrylamide followed by Mannich reaction, a molecular formula of the grafting type starch water treatment agent with flocculation and sterilization functions is expressed as follows: CH-OR;
H H Ho /—O
H CH CH OH ¢=0 Ra R:: H 3k CH:COO Ra: NH» 8% NHCHIN(CH;)2
; LU102511 Where, in the grafting type amphoteric starch water treatment agent, a degree of substitution of anionic groups is 1-50%, a degree of substitution of cationic tertiary amine salt is 5-70%, and the polyacrylamide accounts for 5-80% of the grafting type amphoteric starch water treatment agent.
Further, the anionic starch is separated after etherification reaction of starch and chloroacetic acid.
Further, the starch can be cereal starch, bean starch or potato starch products on the market.
Further, weight average molecular weight of the starch is greater than 50,000.
A preparation method of the grafting type amphoteric starch water treatment agent with flocculation and sterilization functions includes the following steps: (1) preparing anionic starch: dispersing starch into an ethanol solution with a mass percentage of 1-30% of strong alkali, basifying for 0.5-2 hours at a temperature of 20-50 °C; adding chloroacetic acid, where a mass ratio of chloroacetic acid to starch is (0.1:1) to (3:1), a reaction temperature is 30-80 °C and reaction time lasts for 0.5-4 hours in etherification reaction of starch and chloroacetic acid; and filtering after reaction is accomplished and separating to obtain anionic starch; (2) preparing polyacrylamide grafting anionic starch: dissolving the anionic starch obtained in step (1) into water to prepare a solution with a mass percentage of 1-3% of the anionic starch in grafting copolymerization reaction; adding an initiator, a mole number of which is 1%-3% of that of a starch unit under inert gas atmosphere after the solution is uniform; adding acrylamide to react for 1-6 hours at a temperature of 45-65 °C, and taking acetone as a precipitator to precipitate and separate a product after reaction is accomplished, thereby obtaining polyacrylamide grafting anionic starch, where a mass ratio of acrylamide to anionic starch is (0.5:1) to (10:1), (3) preparing the grafting type amphoteric starch water treatment agent with flocculation and sterilization functions: dissolving the polyacrylamide grafting anionic starch obtained in the step (2) into water to prepare a solution with a mass percentage of 1-3% in Mannich reaction; adding a formaldehyde and dimethylamine mixture, reacting for 1-5 hours at a temperature of 20-50 °C, and taking acetone as a precipitator to precipitate and separate a product, thereby obtaining the grafting type amphoteric starch water treatment agent with flocculation and sterilization functions, where a mass ratio of the formaldehyde to the dimethylamine to the polyacrylamide grafting anionic starch is (0.1:0.2:1) to (4:8:1).
Further, in the step (1), the strong alkali is sodium hydroxide or potassium hydroxide.
Further, in the step (2), the initiator is ceric ammonium nitrate or ammonium persulfate or potassium persulfate, where a mole number of the initiator is 2% of that of the starch unit.
Further, in the step (2), the inert gas is nitrogen gas or neon gas or argon gas.
The grafting type amphoteric starch water treatment agent with flocculation and sterilization functions has the beneficial effects that: the water treatment agent is a natural biodegradable material, and has the advantages of being nontoxic and free of secondary pollution, excellent in flocculation effect and good in sterilization function. The method is simple in operation, can prepare the water treatment agent once through a continuous charging method, adopts natural polymer products rich in source, is suitable for large-scale industrial production, and is an economical preparation method for obtaining a high-quality water treatment agent.
Compared with the prior art, the invention has the following advantages that: (1) The grafting type amphoteric starch water treatment agent prepared by the preparation method has triple characteristics of polyacrylamide and cationic and cationic groups; by bonding the three through chemical bonds, a grafting type amphoteric starch water treatment agent material is increased in molecular weight because of anionic and cationic groups rich on the molecular chain, has amphoteric characters, improves water solubility of starch, strengthens the bonding, bridging and flocculating effect, and is endowed with bacteria inhibition and sterilization functions.
(2) Besides, the grafting type amphoteric starch water treatment agent can be suitable for treating water with different charges because of positive charge on cationic groups and negative charge on anionic carboxylic groups,
has good salt resistance, is wider in range of application, is applicable to an acidic medium and an alkali medium, has à wider appliable pH value range of about 1-12.
(3) The high polymer material is wide in source and is low in price; the grating type amphoteric starch water treatment agent has a higher cost performance; the starch natural biodegradable material has the characteristics of being nontoxic, not generating secondary pollution on water and being free of secondary pollution. The product has high efficiency, and is low in dosage, generalty 0.1-10 mg/L.
(4) a quaternary ammonium salt group with sterilization performance is introduced onto a grafting chain to prepare a multifunctional water treatment agent with flocculation and sterilization functions to solve the problems that dosage of a fungicide is increased and content of halogen-containing disinfection byproducts in water is increased and the like as a result of standard-exceeding content of bacteria in water, and thus, the water treatment agent has a very good application prospect.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Further description is made below for the invention with reference to the embodiments. It will be understood that these embodiments are illustrative and that the scope of the invention is not limited to them.
The invention provides a grafting type amphoteric starch water treatment agent with flocculation and sterilization functions which is a grafting type amphoteric starch water treatment agent obtained by virtue of grafting copolymerization of anionic starch and acrylamide followed by Mannich reaction, where a molecular formula of the grafting type amphoteric starch water treatment agent with flocculation and sterilization functions is expressed as follows: CH-OR,
H H HO) —O~ H CH-CH3; OH ¢=0 R: Ry: H 54 CH-COO Rx: NH» 8% NHCH+N(CH;)- Where, in the grafting type amphoteric starch water treatment agent, a degree of substitution of anionic groups is 1-50%, a degree of substitution of cationic tertiary amine salt is 5-70%, and the polyacrylamide accounts for 5-80% of the grafting type amphoteric starch water treatment agent.
Further, the anionic starch is separated after etherification reaction of starch and chloroacetic acid.
Further, the starch can be cereal starch, bean starch or potato starch products on the market.
Further, weight average molecular weight of the starch is greater than 50,000.
The reaction principle of the invention is as shown in formula 2: CH,OH CHLOR | CHLOR; au CICH-COON a Cet or $047 au IL 110) 0m — H po Ome —— H Ho JO Il H CH= CLICONI, H . | CCl OH H OH OH OI (=0 Nil, CILOR | Rız H or CHCOO Op HCIO ! — > oq JO 1EN(C'H3)2 H Cli ON =u Ra: NH or NHCHN(CH 3) Ra Formula 2
A preparation method of the grafting type amphoteric starch water treatment agent with flocculation and sterilization functions includes the following steps:
(1) preparing anionic starch: dispersing starch into an ethanol solution with a mass percentage of 1-30% of strong alkali, basifying for 0.5-2 hours at a temperature of 20-50 °C; adding chloroacetic acid, where a mass ratio of chloroacetic acid to starch is (0.1:1) to (3:1), a reaction temperature is 30-80 °C and reaction time lasts for 0.5-4 hours in etherification reaction; and filtering after reaction is accomplished and separating to obtain anionic starch;
(2) preparing polyacrylamide grafting anionic starch: dissolving the anionic starch obtained in step (1) into water to prepare a solution with a mass percentage of 1-3% of the anionic starch in grafting copolymerization reaction;
adding an initiator, a mole number of which is 1%-3% of that of a starch unit na under inert gas atmosphere after the solution is uniform; adding acrylamide to react for 1-6 hours at a temperature of 45-65 °C, and taking acetone as a precipitator to precipitate and separate a product after reaction is accomplished, thereby obtaining polyacrylamide grafting anionic starch, where a mass ratio of acrylamide to anionic starch is (0.5:1) to (10:1); and (3) preparing the grafting type amphoteric starch water treatment agent with flocculation and sterilization functions: dissolving the polyacrylamide grafting anionic starch obtained in the step (2) into water to prepare a solution with a mass percentage of 1-3% in Mannich reaction; adding a formaldehyde and dimethylamine mixture, reacting for 1-5 hours at a temperature of 20-50 °C, and taking acetone as a precipitator to precipitate and separate a product, thereby obtaining the grafting type amphoteric starch water treatment agent with flocculation and sterilization functions, where a mass ratio of the formaldehyde to the dimethylamine to the polyacrylamide grafting anionic starch is (0.1:0.2:1) to (4:8:1).
In the step (1), the strong alkali is sodium hydroxide or potassium hydroxide.
in the step (2), the initiator is ceric ammonium nitrate or ammonium persulfate or potassium persulfate, where a mole number of the initiator is 2% of that of the starch unit.
In the step (2), the inert gas is nitrogen gas or neon gas or argon gas.
In the following embodiments, the raw material starch used is corn starch produced by Shandong Binzhou Jinhui Corn Development Co., Ltd., and the weight average molecular weight is 150,000.
Embodiment 1 A preparation method of the grafting type amphoteric starch water treatment agent with flocculation and sterilization functions included the following steps that: (1) Starch was dispersed into an ethanol solution with a mass percentage of 5% of sodium hydroxide, and basified for 1 hour at a temperature of 50 °C; then, chloroacetic acid was added and reacted for 4 hours at a temperature of 50 °C, where a mass ratio of chloroacetic acid to starch was 0.5 to 1; and filtering was performed after reaction was accomplished to obtain anionic starch.
(2) The anionic starch obtained in step (1) was dissolved into water to prepare a solution with a mass percentage of 1% of the anionic starch; ammonium persulfate was added as an initiator under atmosphere of neon gas after the solution was uniform, where dosage of the ammonium persulfate was 2% of a mole number of the starch unit; and acrylamide was added and reacted for 4 hours at a temperature of 45 °C, acetone was added as a precipitator to precipitate and separate a product, namely polyacrylamide grafting anionic starch, where a mass ratio of acrylamide to anionic starch is was 5 to 1.
(3) the polyacrylamide grafting anionic starch was dissolved into water to na prepare a solution with a mass percentage of 1%; a formaldehyde and dimethylamine mixture was added and reacted for 3 hours at a temperature of 50 °C after the solution was uniform, and acetone was taken as a precipitator to precipitate and separate a product, namely the grafting type amphoteric starch water treatment agent, where a mass ratio of the formaldehyde to the dimethyiamine to the polyacrylamide grafting anionic starch was 1 to 4 to 2.
The water treatment agent is a natural biodegradable material, and has the advantages of being nontoxic and free of secondary pollution, excellent in flocculation effect and good in sterilization function. The method is simple in operation, cam prepare the water treatment agent once through a continuous charging method, adopts natural polymer products rich in source, is suitable for large-scale industrial production, and is an economical preparation method for obtaining a high-quality water treatment agent.
Compared with the prior art, the invention has the following advantages that: (1) The grafting type amphoteric starch water treatment agent prepared by the preparation method has triple characteristics of polyacrylamide and cationic and cationic groups; by bonding the three through chemical bonds, a grafting type amphoteric starch water treatment agent material is increased in molecular weight because of anionic and cationic groups rich on the molecular chain, has amphoteric characters, improves water solubility of starch,
strengthens the bonding, bridging and flocculating effect, and is endowed with Hess bacteria inhibition and sterilization functions.
(2) Besides, the grafting type amphoteric starch water treatment agent can be suitable for treating water with different charges because of positive charge on cationic groups and negative charge on anionic carboxylic groups, has good salt resistance, is wider in range of application, is applicable to an acidic medium and an alkali medium, has a wider appliable pH value range of about 1-12.
(3) The high polymer material is wide in source and is low in price; the grating type amphoteric starch water treatment agent has a higher cost performance; the starch natural biodegradable material has the characteristics of being nontoxic, not generating secondary pollution on water and being free of secondary poliution. The product has high efficiency, and is low in adding amount, generally 0.1-10 mg/L.
(4) a quaternary ammonium salt group with sterilization performance is introduced onto a grafting chain to prepare a multifunctional water treatment agent with flocculation and sterilization functions to solve the problems that dosage of a fungicide is increased and content of halogen-containing disinfection byproducts in water is increased and the like as a result of standard-exceeding content of bacteria in water, and thus, the water treatment agent has a very good application prospect.
According to analysis adopting a nuclear magnetic method, a degree of substitution of anionic groups is 20%, a degree of substitution of cationic tertiary amine salt is 30%, and the polyacrylamide accounts for 62% of the grafting type amphoteric starch water treatment agent. Infrared spectrums of starch, anionic starch, polyacrylamide grafting anionic starch and the amphoteric grafting type starch water treatment agent material are seen in Fig. 1. From Fig. 1, see an O-H characteristic absorption peak with a wavenumber of 3300 cm‘, an amide extensional vibration peak with a wavenumber of about 1600 cm”, a cationic tertiary amine group characteristic absorption peak with a wavenumber of about 1555 cm, thus proving that the grafting type amphoteric starch water treatment agent with flocculation and sterilization functions is prepared successfully.
Fig. 2 is a schematic diagram showing a flocculation effect, on kaolin suspension, of the grafting type amphoteric starch water treatment agent with flocculation and sterilization functions in the invention. Fig. 3 is schematic diagram showing a sterilization removal effect, on Escherichia coli, of the grafting type amphoteric starch water treatment agent with flocculation and sterilization functions in the invention. The water treatment agent separately takes kaolin suspension (1.0 g/L) and Escherichia coli suspension (1.0x108 CFU/mL) as a simulated water sample; while the pH value is 4, practical flocculation and sterilization effect is observed through a spectrophotometer (wavelength being 630 nm). Seen from Fig. 2, the flocculation effect is the best and a water removal rate is 98% or higher while dosage of the water treatment agent is 1.2 mg/L for the kaolin suspension. Seen from Fig. 3, the sterilization effect is the best and a removal rate of a water sample is 95% or higher while dosage of the water treatment agent is 50 mg/L for the Escherichia coli suspension.
Embodiment 2 The difference between the Embodiment 2 and the Embodiment 1 is that: a preparation method of the grafting type amphoteric starch water treatment agent with flocculation and sterilization functions included the following steps that: (1) starch was dispersed into an ethanol solution with a mass percentage of 1% of potassium hydroxide, and basified for 20 hours at a temperature of °C: then, chloroacetic acid was added and reacted for 4 hours at a temperature of 30 °C, where a mass ratio of chloroacetic acid to starch was
0.1 to 1; and filtering was performed after reaction was accomplished to obtain anionic starch.
(2) The anionic starch was dissolved into water to prepare a solution with a mass percentage of 3% of the anionic starch; potassium persulfate was added as an initiator under atmosphere of argon gas after the solution was uniform, where dosage of the potassium persulfate was 1% of a mole number of the starch unit; and acrylamide was added and reacted for 1 hour at a temperature of 65 °C, acetone was added as a precipitator to precipitate and separate a product, namely polyacrylamide grafting cation starch, where a mass ratio of acrylamide to anionic starch is was 0.5 to 1; (3) the polyacrylamide grafting cation starch was dissolved into water to prepare a solution with a mass percentage of 3%; a formaldehyde and dimethylamine mixture was added and reacted for 5 hours at a temperature of
°C after the solution was uniform, and acetone was taken as a precipitator to precipitate and separate a product, namely the grafting type amphoteric starch water treatment agent, where a mass ratio of the formaldehyde to the dimethylamine to the polyacrylamide grafting cation starch was 0.1 to 0.2 to 1.
According to analysis adopting a nuclear magnetic method, where a degree of substitution of anionic groups is 1%, a degree of substitution of cationic tertiary amine salt is 5%, and the polyacrylamide accounts for 5% of the grafting type amphoteric starch water treatment agent. The water treatment agent separately takes kaolin suspension (1.0 g/L) and Escherichia coli suspension (1.02108 CFU/mL) as a simulated water sample; while the pH value is 4, practical flocculation and sterilization effect is observed through a spectrophotometer (wavelength being 630 nm). A water removal rate is 98% or higher while dosage of the water treatment agent is 2.4 mg/L for the kaolin suspension; and a removal rate of a water sample is 95% or higher while dosage of the water treatment agent is 80 mg/L for the Escherichia coli suspension.
Embodiment 3 The difference between the Embodiment 3 and the Embodiment 1 is that: a preparation method of the grafting type amphoteric starch water treatment agent with flocculation and sterilization functions included the following steps that: (1) starch was dispersed into an aqueous solution with a mass percentage of 15% of sodium hydroxide, and basified for 2 hours at a temperature of 40 °C; then, chloroacetic acid was added and reacted for 0.5 hour at a temperature of 80 °C, where a mass ratio of chloroacetic acid to starch was 3 to 1, and filtering was performed after reaction was accomplished to obtain anionic starch.
(2) The anionic starch was dissolved into water to prepare a solution with a mass percentage of 2% of the anionic starch; potassium persulfate was added as an initiator under atmosphere of nitrogen gas after the solution was uniform, where dosage of the potassium persulfate was 3% of a mole number of the starch unit; and acrylamide was added and reacted for 6 hours at a temperature of 55 °C, acetone was added as a precipitator to precipitate and separate a product, namely polyacrylamide grafting cation starch, where a mass ratio of acrylamide to anionic starch is was 10 to 1; (3) the polyacrylamide grafting cation starch was dissolved into water to prepare a solution with a mass percentage of 2%; a formaldehyde and dimethylamine mixture was added and reacted for 1 hour at a temperature of 50 °C after the solution was uniform, and acetone was taken as a precipitator to precipitate and separate a product, namely the grafting type amphoteric starch water treatment agent, where a mass ratio of the formaldehyde to the dimethylamine to the polyacrylamide grafting cation starch was 4 to 8 to 1.
According to analysis adopting a nuclear magnetic method, where a degree of substitution of anionic groups is 50%, a degree of substitution of cationic tertiary amine salt is 70%, and the polyacrylamide accounts for 80% of the grafting type amphoteric starch water treatment agent. The water treatment agent separately takes kaolin suspension (1.0 g/L) and Escherichia coli suspension (1.0<10$ CFU/mL) as a simulated water sample; while the pH value is 4, practical flocculation and sterilization effect is observed through a spectrophotometer (wavelength being 630 nm). A water removal rate is 98% or higher while dosage of the water treatment agent is 1.3 mg/L for the kaolin suspension; and a removal rate of a water sample is 95% or higher while dosage of the water treatment agent is 55 mg/L for the Escherichia coli suspension.
BRIEF DESCRIPTION OF THE FIGURES For ease of illustration, the invention will be further described in detail in combination with drawings and specific embodiments.
Fig. 1 is an infrared spectrum of each substance in the invention.
Fig. 2 is a schematic diagram showing a flocculation effect, on kaolin suspension, of the grafting type amphoteric starch water treatment agent with flocculation and sterilization functions in the invention.
Fig. 3 is schematic diagram showing a sterilization removal effect, on Escherichia coli, of the grafting type amphoteric starch water treatment agent with flocculation and sterilization functions in the invention.
Where: 1. starch; 2. anionic starch; 3. polyacrylamide grafting anionic starch; and 4. grafting type amphoteric starch water treatment agent with flocculation and sterilization functions.
Claims (8)
1. A grafting type amphoteric starch water treatment agent with flocculation and sterilization functions, characterized by being a grafting type amphoteric starch water treatment agent which is obtained by virtue of grafting copolymerization of anionic starch and acrylamide followed by Mannich reaction, wherein a molecular formuia of the grafting type amphoteric starch water treatment agent with flocculation and sterilization functions is expressed as follows: CH OR:
H
H H HO /— Om H CH-CH+, OH ¢=0 R; Ry: H 8% CH:COO Ra: NH» 5% NHCH,N(CH3)» wherein in the grafting type amphoteric starch water treatment agent, a degree of substitution of anionic groups is 1-50%, a degree of substitution of cationic tertiary amine salt is 5-70%, and the polyacrylamide accounts for 5-80% of the grafting type amphoteric starch water treatment agent.
2. The grafting type amphoteric starch water treatment agent with flocculation and sterilization functions according to claim 1, wherein the anionic starch is separated after etherification reaction of starch and chloroacetic acid.
3. The grafting type amphoteric starch water treatment agent with flocculation and sterilization functions according to claim 1, wherein the starch can be cereal starch, bean starch or potato starch products on the market.
4. The grafting type amphoteric starch water treatment agent with flocculation and sterilization functions according to claim 1, wherein weight average molecular weight of the starch is greater than 50,000.
5. A preparation method for the grafting type amphoteric starch water treatment agent with flocculation and sterilization functions, characterized by comprising the following steps: (1) preparing anionic starch: dispersing starch into an ethanol solution with a mass percentage of 1-30% of strong alkali, basifying for 0.5-2 hours at a temperature of 20-50 °C; adding chloroacetic acid, where a mass ratio of chloroacetic acid to starch is (0.1:1) to (3:1), a reaction temperature is 30-80 °C and reaction time lasts for 0.5-4 hours in etherification reaction of starch and chloroacetic acid; and filtering after reaction is accomplished and separating to obtain anionic starch; (2) preparing polyacrylamide grafting anionic starch: dissolving the anionic starch obtained in step (1) into water to prepare a solution with a mass percentage of 1-3% of the anionic starch in grafting copolymerization reaction; adding an initiator, a mole number of which is 1%-3% of that of a starch unit under inert gas atmosphere after the solution is uniform; adding acrylamide to react for 1-6 hours at a temperature of 45-65 °C, and taking acetone as a precipitator to precipitate and separate a product after reaction is accomplished, thereby obtaining polyacrylamide grafting anionic starch, where a mass ratio of acrylamide to anionic starch is (0.5:1) to (10:1); and (3) preparing the grafting type amphoteric starch water treatment agent with flocculation and sterilization functions: dissolving the polyacrylamide grafting anionic starch obtained in the step (2) into water to prepare a solution with a mass percentage of 1-3% in Mannich reaction; adding a formaldehyde and dimethylamine mixture, reacting for 1-5 hours at a temperature of 20-50 °C, and taking acetone as a precipitator to precipitate and separate a product, thereby obtaining the grafting type amphoteric starch water treatment agent with flocculation and sterilization functions, where a mass ratio of the formaldehyde to the dimethylamine to the polyacrylamide grafting anionic starch is (0.1:0.2:1) to (4:8:1).
6. The preparation method for the grafting type amphoteric starch water treatment agent with flocculation and sterilization functions according to claim 5, wherein in the step (1), the strong alkali is sodium hydroxide or potassium hydroxide.
7. The preparation method for the grafting type amphoteric starch water treatment agent with flocculation and sterilization functions according to claim 5, wherein in the step (2), the initiator is ceric ammonium nitrate or ammonium persulfate or potassium persulfate, and a mole number of the initiator is 2% of that of the starch unit.
8. The preparation method for the grafting type amphoteric starch water treatment agent with flocculation and sterilization functions according to claim 5, wherein in the step (2), the inert gas is nitrogen gas or neon gas or argon gas.
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