CN101264440A - Preparation of iron modified natural STI zeolite defluorination material and regeneration method - Google Patents
Preparation of iron modified natural STI zeolite defluorination material and regeneration method Download PDFInfo
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- CN101264440A CN101264440A CNA2008100347331A CN200810034733A CN101264440A CN 101264440 A CN101264440 A CN 101264440A CN A2008100347331 A CNA2008100347331 A CN A2008100347331A CN 200810034733 A CN200810034733 A CN 200810034733A CN 101264440 A CN101264440 A CN 101264440A
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Abstract
The invention relates to a preparation method and regeneration method for an iron modified natural STI zeolite fluoride removal material, which is characterized in that: a natural zeolite is adopted as raw material, and the natural zeolite Matrix fluoride removal material is obtained through ammonia exchanging, high temperature roasting under protection of nitrogen, and iron modification. The fluoride removal material has the advantages of ability to effectively reduce fluorine content in water to reach the drinking water national standard after the fluoride removal material is mixed with high fluorine water according to a solid-liquid ratio and is statically adsorbed for 2 hours. The fluoride removal material prepared by the method has the advantages of high mechanical strength, good fluoride removal effect, easy and timesaving operation, low energy consumption and disposal cost, and ability to renew the adsorption properties after pickling and iron modification again, repeated use and no secondary pollution for drinking water.
Description
Technical field
The present invention relates to a kind of preparation method and renovation process of iron modified natural STI zeolite defluorination material, belong to environmental protection technical field.
Background technology
Fluorine is one of trace element of needed by human, and an amount of fluorine can strengthen the robustness of bone, and certain carious tooth effect of preventing and treating is arranged.The fluorine of taking in too much can damage health again, causes fluorine dental plaque and fluorosis of bone; Serious caused human body pain in low back and legs, anchylosis, hunchback even paraplegia; Also can cause the thyroid function imbalance, renal dysfunction etc.Drinking-water is the main source that human body is taken in fluorine, and the drinking water fluorinated volume is higher to be the big problem that China exists, and also is a worldwide problem.According to statistics, China has 7,700 ten thousand populations to drink the underground water that fluorinated volume exceeds standard approximately, spreads all over 27 provinces, municipalities and autonomous regions.Drink the endemic fluorosis that high-fluorine water causes, its morbidity area is wide, and more than the patient, the state of an illness is serious, to the influence of people's health and economic development, has become very important social development problem of China.Although department of the Chinese government is making extensive work aspect control endemic fluorosis and the harm of elimination fluorine, thoroughly effecting a radical cure the fluorine disease also needs a lot of roads to walk.It is significant to study cost-effective defluorination method.
At present, still (China's drinking water standard regulation fluoride is no more than 1.0mg/L to fluorine content above required standard in the drinking water source in China high fluorine area, in the drinking water standard of The World Health Organization's suggestion, fluoride concentration is 1.5mg/L), generally reach 3mg/L, some area surpasses 10mg/L.Currently a large amount of research has been carried out in the processing of fluorinated water both at home and abroad, defluorinating process and relevant fundamental research have also been obtained some progress.The physico-chemical process that is usually used in removal of fluorine from water mainly contains coagulant sedimentation, adsorption filtration method, chemical precipitation method, hyperfiltration, electroosmose process, electrocoagulation etc.Wherein, study more with adsorption filtration method, hyperfiltration, electrocoagulation.
But hyperfiltration also is widely adopted in China at present, mainly is owing to lacking (having only 1-3 usually) in higher, the easy pollution of reverse osmosis membrane assembly price, service life.Be limited to factor in many ways such as economic technology, this method is generally used also unrealistic in the rural area.Electrocoagulation is used for removal of fluorine from water, and energy consumption is big, and operation is stable inadequately, also need solve and how further improve fluorine removing rate, problems such as the block film of how adopting an effective measure polarization fouling.
The adsorption filtration method mainly utilizes suction-operated, ion exchange or the complexing etc. of adsorbent and fluorine ion with fluoride ion removing.But the restriction of the main sorbent suspension kind of the height of defluorination effect.Adsorbent commonly used has activated alumina, bone black, activated magnesia, flyash, chelating resin etc., and its shortcoming amount of being to use is big, the defluorination finite capacity, and regeneration is frequent, causes secondary pollution problems easily.
Summary of the invention
The preparation method who the purpose of this invention is to provide a kind of iron modified natural STI zeolite defluorination material.
Another object of the present invention provides a kind of renovation process of iron modified natural STI zeolite defluorination material.
The objective of the invention is to be achieved through the following technical solutions.
A kind of preparation method of iron modified natural STI zeolite defluorination material is characterized in that this method has following processing step:
A.NH
4-STI prepare zeolite: natural STI zeolite 1mol/L NH
4Cl solution is at 95 ℃ of exchanges 3 times, each 2 hours, the quality of natural STI zeolite and 1mol/L NH
4The ratio of the volume of Cl solution is 1: 10～1: 15, and wherein the mass unit of STI zeolite is gram, NH
4The volume unit of Cl solution is a milliliter, and exchange is finished the back and washed and obtain NH 80 ℃ of oven dry
4-STI zeolite;
B.H-STII prepare zeolite: with NH
4-STI zeolite adopts temperature programming, and programming rate is 10 ℃/min, obtains the H-STI zeolite in 2～3 hours 500～550 ℃ of roastings under nitrogen protection;
C. iron MODIFIED Fe (III)-STI prepare zeolite: H-STI zeolite 1mol/L FeCl
3Solution is at 80～90 ℃ of exchanges 3 times, each 2 hours, the quality of H-STI zeolite and 1mol/LFeCl
3The ratio of the volume of solution is 1: 10～1: 15, and wherein the mass unit of STI zeolite is gram, FeCl
3The volume unit of solution is a milliliter, and exchange is finished the back and washed and 80 ℃ of oven dry, make Fe (III)-STI zeolite through high-temperature roasting under nitrogen protection.
A kind of renovation process of iron modified natural STI zeolite defluorination material is characterized in that this method has following technology:
To lose Fe (the III)-STI zeolite of adsorption capacity and 2mol/LHCl solution room temperature exchange 1 time, each 2 hours, exchange was finished the back and is washed and 80 ℃ of oven dry, use 1mol/LFeCl again
3Solution is at 80～90 ℃ of exchanges 3 times, each 2 hours, the quality of Fe (III)-STI zeolite and 1mol/L FeCl
3The ratio of the volume of solution is 1: 10～1: 15, and wherein the mass unit of Fe (III)-STI zeolite is gram, FeCl
3The volume unit of solution is a milliliter, and exchange is finished back washing and 80 ℃ of oven dry, made Fe (the III)-STI zeolite of regenerating through high-temperature roasting under nitrogen protection.
Raw material used in the present invention are the rich natural minerals CXN zeolites that produce of China, and of high grade, reserves are big, and cost of winning is low, and its matrix topology is STI (stilbite) type, belongs to rich ca-form zeolite, is a kind of new natural mineral resource that has wide application prospects.Structure cell consists of Na
0.2Mg
0.1Ca
8.4[Al
17.2Si
54.8O
144] 65H
2O, include in its skeleton structure the ten-ring duct (along [100] direction, 0.49nm * 0.62nm) and the octatomic ring duct that intersects (along [101] direction, 0.27nm * 0.56nm), zeolitic frameworks silica alumina ratio (Si/Al=3.2).When the STI zeolite by the iron modification contacts with fluorine-containing solution, F
-Ion is by diffusing into the duct of zeolite crystal, and and Fe
3+Complexing takes place, and generates FeFn
3-n(n=1～6), thus its chemical adsorption capacity strengthened greatly, while Fe
3+With F
-Complexing, other anion such as HCO in the drinking water
3 -, CO
3 2-, SO
4 2-, Cl
-Disturb lessly, illustrate that the iron modified zeolite is to F
-Very high selectivity is arranged.
The invention provides a kind of preparation method and the renovation process thereof that can effectively remove the defluorination material of excess fluoride in the drinking water.High-fluorine water can reach the drinking water standard (1mg/L) of national regulation after the static absorption of Fe (III)-STI zeolite (2h).This defluorination material energy consumption and processing cost are low, and mechanical strength height, defluorination effect are good, the water after the processing do not have smell, tasteless, nontoxic.This defluorination material non-metallic ion seepage can not cause secondary pollution to drinking water.Prepare Fe (III)-STI zeolite defluorination material among the present invention and be used for removing and contain fluorine drinking water, its static saturated adsorption capacity can reach 2.1mg (fluorine ion)/g (zeolite).Among the present invention, Fe (the III)-STI zeolite that loses adsorption capacity recovers absorption property after pickling, iron modification, can use repeatedly.
Description of drawings
Fig. 1 is the adsorption curve of static adsorption time to the defluorination effect influence.As can be seen behind 15min, F in the protofluorine water
-Concentration is dropped to below the national drinking water standard 1mg/L by 5mg/L, reaches adsorption equilibrium in 2h substantially, and the fluorine ion equilibrium concentration is 0.32mg/L.The result shows that this material defluorination effect is fast.
Fig. 2 is the adsorption isotherm of iron modification STI zeolite when different fluorinion concentration.The result shows that this material is 2.1mg/g to the saturated extent of adsorption of fluorine in the drinking water.
The specific embodiment
The invention will be further described below in conjunction with embodiment:
The modified zeolite of different anions iron salt solutions is to the influence of defluorination effect
Adopt the different anions iron salt solutions that natural minerals STI zeolite is carried out modification and make different Fe (III)-STI zeolite.With FeCl
3Concrete preparation method is as follows as Fe (the III)-STI zeolite of iron salt solutions for solution:
(1) NH
4-STI prepare zeolite: natural STI zeolite 1mol/L NH
43 times (each 2 hours) of 95 ℃ of exchanges of Cl solution, solid-to-liquid ratio 1: 10 (quality of natural STI zeolite and 1mol/LNH
4The ratio of the volume of Cl solution), wherein the mass unit of STI zeolite is gram, NH
4The volume unit of Cl solution is a milliliter, and exchange is finished the back and washed and make NH 80 ℃ of oven dry
4-STI zeolite.
(2) H-STI prepare zeolite: with NH
4-STI zeolite adopts (10 ℃/min) made the H-STI zeolite in the following 550 ℃ of roasting 2-3 of nitrogen protection hours of temperature programmings.
(3) iron MODIFIED Fe (III)-STI prepare zeolite: H-STI zeolite 1mol/L FeCl
33 times (each 2 hours) of 80～90 ℃ of exchanges of solution, solid-to-liquid ratio 1: 10 (quality of H-STI zeolite and 1mol/LFeCl
3The ratio of the volume of solution), wherein the mass unit of STI zeolite is gram, FeCl
3The volume unit of solution is a milliliter, and exchange is finished the back and washed and 80 ℃ of oven dry, make Fe (III)-STI zeolite through high-temperature roasting under the nitrogen protection.
With Fe (NO
3)
3Solution, Fe
2(SO
4)
3Solution as the method for Fe (the III)-STI zeolite of iron salt solutions preparation as mentioned above, only with the 1mol/LFeCl in the step (3)
3Solution is respectively with 1mol/L Fe (NO
3)
3Solution, Fe
2(SO
4)
3Solution replaces.
Accurately take by weighing Fe (the III)-STI zeolite 1g for preparing after the different iron salt solutions modifications, put that to add 100mL concentration behind the plastic beaker be the fluorine-containing water sample of 5.12mg/L, stir 2h after, suction filtration is got clear liquid, add TISAB cushioning liquid, adopt fluoride ion selective electrode to measure fluorinion concentration.The modified zeolite of different anions molysite is to the influence such as the following table of defluorination effect:
| Iron salt solutions | Protofluorine water concentration (mg/L) | Concentration behind the defluorination (mg/L) | Fluoride removing rate (%) |
| FeCl 3 | 5.12 | 0.32 | 93.8 |
| Fe(NO 3) 3 | 5.12 | 3.2 | 37.5 |
| Fe 2(SO 4) 3 | 5.12 | 3.4 | 33.6 |
Above-mentioned data show, use FeCl
3During solution modification STI zeolite, other cations of the easier replacement of ferric ion are loaded on the zeolite, have improved defluorination effect.
FeCl
3The defluorination effect of modification STI zeolite and the former powder of natural STI zeolite relatively
Fe (III)-STI prepare zeolite step is as embodiment 1.FeCl
3The defluorination effect of modification STI zeolite and the former powder of natural STI zeolite is compared as follows table:
| Adsorbent | Protofluorine water concentration (mg/L) | Concentration behind the defluorination (mg/L) | Fluoride removing rate (%) |
| Unmodified STI zeolite | 5.12 | 3.9 | 23.8 |
| FeCl 3Modification STI zeolite | 5.12 | 0.32 | 93.8 |
Above-mentioned data show, after ferric ion replaces other cations and is loaded on the zeolite, since iron ion and fluorine ion generation complexing, generation FeFn
3-n(n=1～6), thus its chemical adsorption capacity strengthened greatly, the adsorption capacity of adsorbent is greatly increased.
Embodiment 3
Different adsorbents compare the static adsorption capacity that contains fluorine drinking water
With iron modified natural HEU zeolite with commercially available activated alumina, amorphous alumina, activated carbon, calcite, clay, charcoal, bleaching earth, red mud adsorbent as a comparison.
Different adsorbents are to containing the adsorption capacity comparative result such as the following table of fluorine drinking water:
| Adsorbent | Adsorption capacity (mg/g) |
| Activated alumina | 2.4 |
| Amorphous alumina | 3.6 |
| Activated carbon | 1.1 |
| Calcite | 4.37×10 -5 |
| Clay | 7.09 |
| Charcoal | 7.88×10 -5 |
| Bleaching earth | 7.75 |
| Red mud | 6.2810 -3 |
| Iron modification HEU zeolite | ＜1.0 |
| Iron modification STI zeolite (the present invention) | 2.1 |
The computing formula of adsorption capacity is as follows:
Wherein: fluorinion concentration (mg/L) when initial in the Co-solution
Fluorinion concentration (mg/L) during balance in the Ce-solution
V-liquor capacity (L)
W-adsorbent mass (g)
The unit mass adsorbent is to the adsorbance (mg/g) of adsorbate during the qe-adsorption equilibrium
Take all factors into consideration the market price and the adsorption capacity of adsorbent, defluorination material energy consumption of the present invention and processing cost is low, defluorination effect is good, cost performance is outstanding in existing drinking water defluorination material.
Embodiment 4
1g iron modification STI zeolite dosage contains the defluorination effect of fluorine drinking water to 100mL (solid-to-liquid ratio 1: 100) variable concentrations
Fe (III)-STI prepare zeolite step is as embodiment 1.
| Protofluorine water concentration (mg/L) | Adsorption capacity (mg/g) | Fluoride removing rate (%) |
| 5 | 0.46 | 93.8 |
| 10 | 0.87 | 91.1 |
| 15 | 1.18 | 85.7 |
| 30 | 1.98 | 82.6 |
Above-mentioned data show, this material of 1 gram dosage to low fluorine drinking water (＜30mg/L) good defluorination effect arranged.Drinking water water after the processing do not have smell, tasteless, nontoxic.Detect basic non-metallic ion Fe in this adsorbent through ICP-AES
3+Seepage can not cause secondary pollution to drinking water.Improve iron modification STI zeolite using dosage and can remove high-fluorine drinking water.
Embodiment 5
The regeneration test of Fe (III)-STI zeolite adsorbents
After 2mol/LHCl solution room temperature exchange 1 time (2 hours), exchange is finished the back and is washed and 80 ℃ of oven dry, use 1mol/LFeCl again with Fe (III)-STI zeolite of losing adsorption capacity
33 times (each 2 hours) of 80～90 ℃ of exchanges of solution, the quality and the 1mol/LFeCl of Fe (III)-STI zeolite
3The ratio of the volume of solution is 1: 10, and wherein the mass unit of Fe (III)-STI zeolite is gram, FeCl
3The volume unit of solution is a milliliter, and exchange is finished back washing and 80 ℃ of oven dry, made Fe (the III)-STI zeolite of regenerating through high-temperature roasting under nitrogen protection.Repeat the defluorination test of above-mentioned technology and embodiment 1, the result shows that after twice regeneration this adsorbent still has good adsorption performance (fluoride removing rate is greater than 90%).
Claims (2)
1. the preparation method of an iron modified natural STI zeolite defluorination material is characterized in that this method has following processing step:
A.NH
4-STI prepare zeolite: natural STI zeolite 1mol/L NH
4Cl solution is at 95 ℃ of exchanges 3 times, each 2 hours, the quality of natural STI zeolite and 1mol/L NH
4The ratio of the volume of Cl solution is 1: 10～1: 15, and wherein the mass unit of STI zeolite is gram, NH
4The volume unit of Cl solution is a milliliter, and exchange is finished the back and washed and obtain NH 80 ℃ of oven dry
4-STI zeolite;
B.H-STII prepare zeolite: with NH
4-STI zeolite adopts temperature programming, and programming rate is 10 ℃/min, obtains the H-STI zeolite in 2～3 hours 500～550 ℃ of roastings under nitrogen protection;
C. iron MODIFIED Fe (III)-STI prepare zeolite: H-STI zeolite 1mol/LFeCl
3Solution is at 80～90 ℃ of exchanges 3 times, each 2 hours, the quality of H-STI zeolite and 1mol/LFeCl
3The ratio of the volume of solution is 1: 10～1: 15, and wherein the mass unit of STI zeolite is gram, FeCl
3The volume unit of solution is a milliliter, and exchange is finished the back and washed and 80 ℃ of oven dry, make Fe (III)-STI zeolite through high-temperature roasting under nitrogen protection.
2. the renovation process of an iron modified natural STI zeolite defluorination material is characterized in that this method has following technology:
To lose Fe (the III)-STI zeolite of adsorption capacity and 2mol/LHCl solution room temperature exchange 1 time, each 2 hours, exchange was finished the back and is washed and 80 ℃ of oven dry, use 1mol/LFeCl again
3Solution is at 80～90 ℃ of exchanges 3 times, each 2 hours, the quality and the 1mol/LFeCl of Fe (III)-STI zeolite
3The ratio of the volume of solution is 1: 10～1: 15, and wherein the mass unit of Fe (III)-STI zeolite is gram, FeCl
3The volume unit of solution is a milliliter, and exchange is finished back washing and 80 ℃ of oven dry, made Fe (the III)-STI zeolite of regenerating through high-temperature roasting under nitrogen protection.
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Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102285665A (en) * | 2011-06-07 | 2011-12-21 | 天津大学 | Liquid phase chemical deposition modified natural zeolite and method for removing fluorine from water |
| CN101759197B (en) * | 2008-12-26 | 2012-11-14 | 复旦大学 | Mesopore USSTI zeolite with high silicon content and high hydrothermal stability and preparation method thereof |
| CN108408914A (en) * | 2018-04-03 | 2018-08-17 | 温州大学 | Natural zeolite floating bed device is removed based on suspension type ferric ion modified particles activated carbon |
| CN109399663A (en) * | 2018-09-04 | 2019-03-01 | 复榆(张家港)新材料科技有限公司 | The production method of ultra-fine NH4-STI powder |
| CN113694879A (en) * | 2021-08-27 | 2021-11-26 | 国能神东煤炭集团有限责任公司 | Preparation and regeneration method of modified defluorination stone |
| CN113842871A (en) * | 2021-10-19 | 2021-12-28 | 山东建筑大学 | Anti-interference defluorination adsorbent and preparation method thereof |
-
2008
- 2008-03-18 CN CN2008100347331A patent/CN101264440B/en not_active Expired - Fee Related
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101759197B (en) * | 2008-12-26 | 2012-11-14 | 复旦大学 | Mesopore USSTI zeolite with high silicon content and high hydrothermal stability and preparation method thereof |
| CN102285665A (en) * | 2011-06-07 | 2011-12-21 | 天津大学 | Liquid phase chemical deposition modified natural zeolite and method for removing fluorine from water |
| CN102285665B (en) * | 2011-06-07 | 2013-01-16 | 天津大学 | Liquid phase chemical deposition modified natural zeolite and method for removing fluorine from water |
| CN108408914A (en) * | 2018-04-03 | 2018-08-17 | 温州大学 | Natural zeolite floating bed device is removed based on suspension type ferric ion modified particles activated carbon |
| CN109399663A (en) * | 2018-09-04 | 2019-03-01 | 复榆(张家港)新材料科技有限公司 | The production method of ultra-fine NH4-STI powder |
| CN113694879A (en) * | 2021-08-27 | 2021-11-26 | 国能神东煤炭集团有限责任公司 | Preparation and regeneration method of modified defluorination stone |
| CN113842871A (en) * | 2021-10-19 | 2021-12-28 | 山东建筑大学 | Anti-interference defluorination adsorbent and preparation method thereof |
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