CN1247838A - Cationic high-molecular flocculant and its preparation - Google Patents
Cationic high-molecular flocculant and its preparation Download PDFInfo
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- CN1247838A CN1247838A CN 98114326 CN98114326A CN1247838A CN 1247838 A CN1247838 A CN 1247838A CN 98114326 CN98114326 CN 98114326 CN 98114326 A CN98114326 A CN 98114326A CN 1247838 A CN1247838 A CN 1247838A
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Abstract
The flocculant is color-less transparent colloid with amino methyl polyacrylamide as main component. It is prepared by using polyacrylamide, formaldehyde, dimethylamine and deionized water as raw material and persulfate as catalyst and through the processes of dissolving polyacrylamide in water, regulating pH value to 8-9 with caustic alkali, adding catalyst and formaldehyde to react at 48-52 deg.c for one hr and adding dimethylamine to react at 68-72 deg.c for one other hr. The product of the present invention, when being coagulated with particles in liquid, has short coagulation time, large coagulated bulk, and fast sedimentation velocity and the settled sludge can be dewatered completely and produces no secondary pollution.
Description
The present invention relates to a kind of water conditioner, particularly sewage-treating agent.
Investigate the effect of municipal sewage treatment, topmost index is to see the subsequent disposal of mud.It is the key issue of city domestic sewage and Industrial Wastewater Treatment that this mud is dewatered smoothly.The polymeric flocculant major part that use at current domestic sewage work and Industrial Wastewater Treatment station is polyacrylamide (PAM), its dehydration throwing out principle is to be adsorbed as power with bridge formation, thereby making mud form the wadding piece settles down, but the wadding block of Xing Chenging is long-pending little like this, settling velocity is slow, the flocculation dewatering effect is undesirable, causes water, electricity, artificial waste.
The object of the present invention is to provide a kind of existing bridge formation adsorption, cationic high-molecular flocculant of charge neutralization and preparation method thereof is arranged again.
Purpose of the present invention can realize by following measure: a kind of cationic high-molecular flocculant is characterized in that: it is to be the water white transparency colloid of major ingredient with amine methyl polyacrylamide.
The preparation method of above-mentioned cationic high-molecular flocculant is characterized in that:
Following part by weight relation is arranged: polyacrylamide (content is in 100%): formaldehyde (content is in 38%): dimethylamine (content is in 40%): water: persulphate=0.58～1.17: 0.80～0.9: 1: 46～50: 0.0021～0.003 between A, reaction raw materials and catalyzer
B, operation steps are as follows:
A, polyacrylamide be added to deionized water for stirring make it to dissolve fully,
B, adding caustic-alkali aqueous solution are adjusted the pH value of solution, make it between 8～9,
C, adding persulphate catalyzer,
D, adding formaldehyde, control reaction temperature are at 48～52 ℃, and formaldehyde added the back insulation reaction 1 hour,
E, adding dimethylamine, control reaction temperature are at 68～72 ℃, and dimethylamine added the back insulation reaction 1 hour.Above-mentioned polyacrylamide is to adopt following method preparation, is to add deionized water in 30% acrylamide monomer to content promptly, and the content that makes acrylamide is 8～10%, adds 2.1 * 10 of acrylamide weight again
-4～3 * 10
-4Persulphate catalyzer doubly, under 60 ℃ of temperature, stirring reaction 10～60 minutes.Air in the most handy nitrogen replacement reaction vessel, and nitrogen gas pressure is 2～3kg/cm
2Used water is deionized water.
Polymeric flocculant of the present invention is a water white transparency shape colloid, soluble in water, molecular weight 1000～1,200 ten thousand, and density is 5.4 (25 ℃), proportion 0.93 (25 ℃), pH value 8.0 ± 0.1 (1% aqueous solution).The major ingredient of this flocculation agent is an amine methyl polyacrylamide, and its structural formula is as follows:
It is to be raw material, to be prepared from having under the condition of catalyzer that with polyacrylamide, dimethylamine and formaldehyde its chemical equation is as follows:
Main raw material of the present invention is a polyacrylamide, and its molecular weight is more than 5,000,000.Raw material of the present invention also has formaldehyde, dimethylamine, water (preferably deionized water) and catalyzer.The catalyzer that the present invention adopts is a persulphate, as Potassium Persulphate, Sodium Persulfate and ammonium persulphate etc.Following part by weight relation is arranged, that is: polyacrylamide (content is in 100%) between the above-mentioned raw materials: formaldehyde (content is in 38%): dimethylamine (content is in 40%): water: persulphate=0.58～1.17: 0.80～0.9: 1: 46～50: 0.0021～0.003.
The preparation technology of flocculation agent of the present invention is as follows:
1, polyacrylamide is joined in water or the deionized water, stirring makes it to dissolve fully.
2, add caustic alkali,, adjust the pH value of solution, make them between 8～9 as caustic soda, Ke Xingjia.
3, add the catalyzer persulphate, and stir.
4, add formaldehyde in above-mentioned solution, control reaction temperature treats that at 48～52 ℃ formaldehyde added the back insulation reaction 1 hour.
5, be warmed up to 68～72 ℃ then, adding dimethylamine and control are reflected under the said temperature to be carried out, and treats that dimethylamine added the back insulation reaction 1 hour, and the water white transparency colloidal solution that obtains is cationic high-molecular flocculant.
Nitrogen gas pressure is 2～3kg/cm in the air in the most handy nitrogen replacement reaction vessel of above-mentioned reaction, reaction vessel
2
Preferably above-mentioned polyacrylamide adopts following method preparation: add deionized water in content is 30% acrylamide monomer, the content that makes acrylamide is 8～10%, adds acrylamide weight 2.1 * 10 again
-4～3 * 10
-4Persulphate catalyzer doubly, stirring reaction is 10～60 minutes under 60 ℃ of temperature, can obtain molecular weight and be the polyacrylamide more than 1,000 ten thousand.
The present invention compared with prior art has following advantage:
1, flocculation agent of the present invention has molecular weight height, positively charged characteristics, and therefore the existing bridge formation adsorption of action principle aspect feedwater and sewage disposal has charge neutralization again.Short with the suspended particle coagulation time in the liquid, the wadding piece of formation is big, and settling velocity is fast, and the wadding piece is more closely knit.Settled sludge dewatering is more thorough, non-secondary pollution.
2, the mud of handling with the polymeric flocculant of the present invention's production can be worked as compound farm manure use, can not cause hardening of soil.
3, flocculation agent preparation technology of the present invention is simple, facility investment is little.Time with short production cycle, polyreaction only is original half, and raw material is easy to get, production cost is low.
4, the correlation data of flocculation agent of the present invention and existing some technical indicator of flocculation agent:
| Molecular weight | Quality viscosity | Flocculation time | Production cycle (8 hours) | |
| Existing flocculation agent flocculation agent of the present invention | Below 1,000 ten thousand 1000～1,200 ten thousand | ?3 ?5～7 | 45 seconds 15 seconds | One class two classes |
Example 1
Get 80 kilograms of acrylamide crystals, be dissolved in the 1000 liter reactors that fill 920 kilograms of deionized waters.Slowly be warmed up to 50 ℃, add 40 gram Potassium Persulphate catalyzer, stir under 60 ℃ of temperature and make it abundant reaction, being incubated and obtaining molecular weight after 1 hour is 1000～1,200 ten thousand polyacrylamide.
Get 850 kilograms of above-mentioned polyacrylamides, contain in being dissolved in the reactor of 4000 kilograms of deionized waters, stirring makes it to dissolve fully.Treat that fully the dissolving back adds the pH value that 5 kilograms of (in 99%) sodium hydroxide are transferred solution, the pH value that makes solution is 8～9.Add 240 gram Potassium Persulphates again, use the air in the nitrogen replacement reaction vessel then, nitrogen gas pressure is 2～3kg/cm in the reaction vessel
2In above-mentioned solution, add 74.4 kilograms of formaldehyde, control reaction temperature at 48～52 ℃, treat that formaldehyde adds after, insulation reaction 1 hour.Continuing then to heat up 68～72 ℃ adds 85 kilograms of dimethylamine, and controls to be reflected under this temperature and carry out, and treats that dimethylamine added the back insulation reaction 1 hour, and the water white transparency colloid that obtains is cationic high-molecular flocculant.
Example 2
Get 250kg content and be 30% acrylamide solution, contain in the 1000 liter reactors of 650kg deionized water in being added to, when slowly being warmed up to 50 ℃, add 32.5 gram ammonium persulphate catalyzer, under 60 ℃ of temperature, stir, make it fully to react blowing after 10 minutes, in the plastic tank of inner lining plastic bag, seal and make it static polymerization, both can obtain polyacrylamide colloid.
Get 124 kilograms of above-mentioned polyacrylamides, contain in being dissolved in the reactor of 727.8 kilograms of deionized waters, stirring makes it to dissolve fully.Treat that fully the dissolving back adds the pH value that 0.8 kilogram of (in 99.8%) sodium hydroxide is transferred solution, the pH value that makes solution is 8～9.Add 100 gram ammonium persulphates again, add 13.6 kilograms of formaldehyde in above-mentioned solution, control reaction temperature is at 48～52 ℃, treat formaldehyde add after insulation reaction one hour.Continue then to heat up 68～72 ℃, add 17.2 kilograms of dimethylamine, and control to be reflected under this temperature and carry out, treat that dimethylamine added the back insulation reaction one hour, obtained water white transparency cationic high-molecular flocculant colloid.
Example 3
Repeat the operation of example 2, wherein polyacrylamide is 238 kilograms, 730 kilograms in tap water, 1 kilogram in potassium hydroxide, Potassium Persulphate 100 grams, 16.6 kilograms in formaldehyde, 19.2 kilograms of dimethylamine.
Example 4
Take by weighing 36 kilograms of non-ionic polyacrylamide dry powder, contain in the 5000 liter reactors of 3000 kilograms of deionized waters in slowly being added to cast feeder, make it abundant dissolving.Treat that fully the dissolving back adds 2.7 kilograms of potassium hydroxide (in content 99.8%) in order to regulate the pH value of above-mentioned solution, the pH value of solution is remained in 8～9 the scope.Add 300 gram Sodium Persulfates again, when making reaction soln be warmed up to 48～50 ℃ then, drip 42 kilograms formaldehyde solution, continue to be warmed up to 68～72 ℃ then, the dimethylamine that adds 50 kilograms again added the back insulation reaction 1 hour, obtained the water white transparency cationic high-molecular flocculant.
Example 5
Repeat the operation of example 4, wherein 8% non-ionic polyacrylamide is 750 kilograms, 2237 kilograms of deionized waters, 2.5 kilograms in sodium hydroxide, Sodium Persulfate 180 grams, 50.8 kilograms in formaldehyde, 60 kilograms of dimethylamine.
Example 6
With content is that 8% the acrylamide monomer aqueous solution directly is drawn in the reactor with impeller pump for 1000 kilograms, temperature of reaction is when 60 ℃ of left and right sides, the Sodium Persulfate that adds 32 grams, stirring makes it abundant reaction, blowing is in the interior plastic tank that is lined with plastics bag after 10 minutes, seal and make it static autohemagglutination, promptly obtain polyacrylamide colloid.
Take by weighing 1230 kilograms of above-mentioned polyacrylamide colloids and be added in the 5000 liter reactors of 3776.4 kilograms of deionized waters of interior Sheng, stir and make it abundant dissolving.Wait to dissolve abundant back and add 4.8 kilograms of (in 100%) aqueous sodium hydroxide solutions, the pH value of adjusting reaction solution is between 8～9.Add 240 gram Sodium Persulfates again.Charge into the air in the nitrogen replacement reactor then, the pressure that keeps reactor is at 2.3kg/cm
2Reaction solution is warmed up to 48～52 ℃, adds after 74.4 kilograms formaldehyde fully reacts 1 hour, when continuing to be warmed up to 68～72 ℃, add 85 kilograms of dimethylamine, isothermal reaction is blowing after 60 minutes, can obtain cationic high-molecular flocculant.
Annotate: the used per-cent of present specification all is weight percentage.Cationic polyacrylamide cationic degree testing method annex 1
One, instrument and reagent:
1, spectrophotometer, band 3cm cuvette;
2, electronics agitator;
3,50ml colorimetric cylinder, 20.
4,1000ml volumetric flask.
5, hydrochloric acid soln: 0.1mol/L.Measure 0.9ml hydrochloric acid, be dissolved in 100ml water, shake all;
6, polyvinylsulfonic acid potassium anion standardized solution: about 0.0025mol/L.
7, add aniline blue: 1% aqueous solution.Take by weighing 1 gram potassium aniline blue, water-soluble, dilution 100ml.
Two, operation steps:
1, accurately takes by weighing 1 gram (being accurate to 0.0002 gram) positively charged ion polyacrylamide powder, under magnetic stirrer stirs, be dissolved in 100ml distilled water, and be transferred in the 1000ml volumetric flask, be diluted to scale, shake up.
2, get 10 50ml colorimetric cylinders, add 2ml solution 1 respectively, hydrochloric acid soln 0.5ml, 1% toluidine blue solution 0.5ml with transfer pipet.Add 0.5,1.0,1.5,2.0,2.5,3.0,3.5,4.0,4.5 then respectively, 5.0ml polyvinylsulfonic acid potassium anion standardized solution, and with distilled water diluting to scale, shake up, leave standstill 5min.Under the 630nm wavelength, make reference with distilled water, measure its absorbancy respectively with the 3cm cuvette.Adding volume with the polyvinyl potassium iodate solution is X-coordinate, marks and draws system absorbancy curve with absorbancy for vertical the biography.
3, replace cationic polyacrylamide solution with distilled water, make blank assay by 2 steps.Being X-coordinate with adding volume with the polyvinylsulfonic acid potassium solution under the system of coordinates, is that ordinate zou is drawn the absorbancy curve with the absorbancy.
Three, calculate
2 the difference of getting on any 2 the corresponding X-coordinates between two absorbancy curve parallel portion is Δ V, is the volume of the negatively charged ion standardized solution that copolymerization cationic polyacrylamide sample consumed.
The cationic degree A that represents with mass percent calculates by formula:
In the formula: the concentration of C polyvinylsulfonic acid potassium solution, mol/L;
▲ V: the volume that the polyvinylsulfonic acid potassium solution consumes, ml;
207.5: the relative molecular mass of DMC chain link in the cationic polyacrylamide;
M: the quality of sample, g;
X: the solid content of sample.
Claims (5)
1, a kind of cationic high-molecular flocculant is characterized in that: it is to be the water white transparency colloid of major ingredient with amine methyl polyacrylamide.
2, the preparation method of above-mentioned cationic high-molecular flocculant is characterized in that:
Following part by weight relation is arranged: polyacrylamide (content is in 100%): formaldehyde (content is in 38%): dimethylamine (content is in 40%): water: persulphate=0.58～1.17: 0.80～0.9: 1: 46～50: 0.0021～0.003 between A, reaction raw materials and catalyzer
B, operation steps are as follows:
A, polyacrylamide be added to deionized water for stirring make it to dissolve fully,
B, adding caustic-alkali aqueous solution are adjusted the pH value of solution, make it between 8～9,
C, adding persulphate catalyzer,
D, adding formaldehyde, control reaction temperature are at 48～52 ℃, and formaldehyde added the back insulation reaction 1 hour,
E, adding dimethylamine, control reaction temperature are at 68～72 ℃, and dimethylamine added the back insulation reaction 1 hour.
3, the preparation method of cationic high-molecular flocculant according to claim 2, it is characterized in that: above-mentioned polyacrylamide is to adopt following method preparation, be to add deionized water in 30% acrylamide monomer promptly to content, the content that makes acrylamide is 8～10%, adds 2.1 * 10 of acrylamide weight again
-4～3 * 10
-4Persulphate catalyzer doubly, under 60 ℃ of temperature, stirring reaction 10～60 minutes.
4, the preparation method of cationic high-molecular flocculant according to claim 2 is characterized in that: with the air in the nitrogen replacement reaction vessel, and nitrogen gas pressure is 2～3kg/cm
2
5, the preparation method of cationic high-molecular flocculant according to claim 2 is characterized in that: used water is deionized water.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 98114326 CN1086181C (en) | 1998-09-17 | 1998-09-17 | Cationic high-molecular flocculant and its preparation |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 98114326 CN1086181C (en) | 1998-09-17 | 1998-09-17 | Cationic high-molecular flocculant and its preparation |
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|---|---|
| CN1247838A true CN1247838A (en) | 2000-03-22 |
| CN1086181C CN1086181C (en) | 2002-06-12 |
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Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100340506C (en) * | 2004-10-29 | 2007-10-03 | 中国石油化工股份有限公司 | Sludge dewatering agent and its preparation method |
| CN102139947A (en) * | 2011-04-15 | 2011-08-03 | 陕西科技大学 | Cationic flocculant |
| CN102557215A (en) * | 2010-12-23 | 2012-07-11 | 陕西蓝清环境科技有限公司 | Compound organic water purifying agent and preparation method thereof |
| CN103102459A (en) * | 2013-01-17 | 2013-05-15 | 杭州电子科技大学 | Preparation method of gelatin grafted acrylamide cation polymeric flocculant |
| CN105198063A (en) * | 2014-06-08 | 2015-12-30 | 蒋寿悟 | Flocculating agent for waste water treatment |
| CN105524196A (en) * | 2014-09-28 | 2016-04-27 | 上海东升新材料有限公司 | Preparation method of high-performance cationic polyacrylamide flocculating agent |
| CN106008822A (en) * | 2016-06-21 | 2016-10-12 | 上海东升新材料有限公司 | Polyacrylamide flocculant modified by chitosan and preparing method thereof |
| CN110499268A (en) * | 2019-08-19 | 2019-11-26 | 仁和堂药业有限公司 | White staphylococcus powder and its application |
| CN112300023A (en) * | 2019-07-31 | 2021-02-02 | 中国石油化工股份有限公司 | Acrylamide monomer and preparation method and application thereof |
| CN114409860A (en) * | 2022-02-28 | 2022-04-29 | 南京瑞迪高新技术有限公司 | Preparation method of organic flocculant for efficiently treating sand washing wastewater |
-
1998
- 1998-09-17 CN CN 98114326 patent/CN1086181C/en not_active Expired - Fee Related
Cited By (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100340506C (en) * | 2004-10-29 | 2007-10-03 | 中国石油化工股份有限公司 | Sludge dewatering agent and its preparation method |
| CN102557215A (en) * | 2010-12-23 | 2012-07-11 | 陕西蓝清环境科技有限公司 | Compound organic water purifying agent and preparation method thereof |
| CN102139947A (en) * | 2011-04-15 | 2011-08-03 | 陕西科技大学 | Cationic flocculant |
| CN103102459A (en) * | 2013-01-17 | 2013-05-15 | 杭州电子科技大学 | Preparation method of gelatin grafted acrylamide cation polymeric flocculant |
| CN103102459B (en) * | 2013-01-17 | 2015-04-15 | 杭州电子科技大学 | Preparation method of gelatin grafted acrylamide cation polymeric flocculant |
| CN105198063A (en) * | 2014-06-08 | 2015-12-30 | 蒋寿悟 | Flocculating agent for waste water treatment |
| CN105524196A (en) * | 2014-09-28 | 2016-04-27 | 上海东升新材料有限公司 | Preparation method of high-performance cationic polyacrylamide flocculating agent |
| CN105524196B (en) * | 2014-09-28 | 2018-03-27 | 上海东升新材料有限公司 | A kind of preparation method of high-performance cationic polyacrylamide flocculant agent |
| CN106008822A (en) * | 2016-06-21 | 2016-10-12 | 上海东升新材料有限公司 | Polyacrylamide flocculant modified by chitosan and preparing method thereof |
| CN112300023A (en) * | 2019-07-31 | 2021-02-02 | 中国石油化工股份有限公司 | Acrylamide monomer and preparation method and application thereof |
| CN112300023B (en) * | 2019-07-31 | 2023-06-16 | 中国石油化工股份有限公司 | Acrylamide monomer, and preparation method and application thereof |
| CN110499268A (en) * | 2019-08-19 | 2019-11-26 | 仁和堂药业有限公司 | White staphylococcus powder and its application |
| CN114409860A (en) * | 2022-02-28 | 2022-04-29 | 南京瑞迪高新技术有限公司 | Preparation method of organic flocculant for efficiently treating sand washing wastewater |
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| CN1086181C (en) | 2002-06-12 |
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