CN108579667A - The preparation method of bentonite/flyash composite particles sorbing material - Google Patents
The preparation method of bentonite/flyash composite particles sorbing material Download PDFInfo
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- CN108579667A CN108579667A CN201810164799.6A CN201810164799A CN108579667A CN 108579667 A CN108579667 A CN 108579667A CN 201810164799 A CN201810164799 A CN 201810164799A CN 108579667 A CN108579667 A CN 108579667A
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- bentonite
- composite particles
- sorbing material
- flyash
- flyash composite
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J20/00—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof
- B01J20/02—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof comprising inorganic material
- B01J20/10—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof comprising inorganic material comprising silica or silicate
- B01J20/12—Naturally occurring clays or bleaching earth
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J20/00—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof
- B01J20/02—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof comprising inorganic material
- B01J20/10—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof comprising inorganic material comprising silica or silicate
- B01J20/103—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof comprising inorganic material comprising silica or silicate comprising silica
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J20/00—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof
- B01J20/28—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof characterised by their form or physical properties
- B01J20/28014—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof characterised by their form or physical properties characterised by their form
- B01J20/28016—Particle form
- B01J20/28019—Spherical, ellipsoidal or cylindrical
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- Organic Chemistry (AREA)
- Chemical Kinetics & Catalysis (AREA)
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- Life Sciences & Earth Sciences (AREA)
- Dispersion Chemistry (AREA)
- Geochemistry & Mineralogy (AREA)
- Solid-Sorbent Or Filter-Aiding Compositions (AREA)
Abstract
The invention discloses a kind of preparation methods of bentonite/flyash composite particles sorbing material, flyash is added in bentonite and the sodium bicarbonate as pore-foaming agent is sufficiently mixed, obtain mixed slurry, mixed slurry prepares bentonite/flyash composite particles of certain grain size by extruder and spheronizator, then in Muffle kiln roasting granulation formation.The technological process of the present invention is simple, easy to operate, and bentonite obtained/flyash composite particles sorbing material has the advantages that size tunable, high mechanical strength and with a high adsorption activity.
Description
Technical field
The invention belongs to waste water, exhaust-gas treatment and its resource technology fields, and extrusion spheronization is used more particularly to a kind of
Method prepares the preparation method of bentonite/flyash composite particles sorbing material
Background technology
Currently, with the fast development of industrial or agricultural, blowdown flow rate is also growing day by day, most unprocessed and in line rivers.Contain
Heavy metal wastewater thereby is discharged into, and makes water pollution, seriously damages health, and generate serious danger to fishery and agricultural production
Evil.Water resource environment problem oneself have become puzzlement China's economic development an important factor for.Based on this, various wastewater treatment absorption
The research of agent is come into being, and is continued to develop.Common adsorbent is activated carbon in industry at present, but it is expensive and regenerates
It is difficult, it is therefore desirable to develop cheap, dependable performance, be easy to regenerated water treatment absorbent to adapt to environmental protection industry development
It needs.
Now oneself develops the treatment technology of various heavy waste water both at home and abroad, wherein what is be concerned is with cheap swelling
The clay minerals such as soil and flyash equal industrial residue remove the treatment technology of the heavy metal ion in waste water as sorbing material.
Clay mineral and flyash modified all have high-adsorption-capacity and stronger adsorption bleaching ability, have in the treatment of waste water
There is prodigious application potential.Currently, the sorbing materials such as bentonite, flyash exist as follows in heavy metal containing wastewater treatment application
Main problem:
(1) the clay minerals fine size such as bentonite easily disperses dusting after meeting water, causes subsequent handling to be separated by solid-liquid separation difficult,
A large amount of sludge is generated simultaneously, generates secondary pollution.
(2) there is the research report that bentonite is granulated by hand in the country at present, but generally existing granular size is uneven, mechanical strength
The problems such as low and adsorption effect is unstable, result of study also rests on laboratory simulation, without practical application.
(3) adsorption-desorption of clay mineral is studied more, it is desorbed, research is less in terms of regeneration, cause to inhale
Attached dose cannot reuse so that processing cost increases.
(4) although flyash has certain absorption property, but also needs to further increase.How fly ash base absorption is improved
The absorption property of material is the hot subject of current domestic and foreign scholars' research.
So far there is not yet the research for being prepared bentonite/flyash composite particles sorbing material using extrusion spheronization method is reported.
Invention content
In view of this, using extrusion spheronization method, to prepare bentonite/flyash compound the purpose of the present invention is to provide a kind of
The preparation method of particulate adsorbent material is lived with the mechanical strength and absorption that improve bentonite/flyash composite particles sorbing material
Property.
In order to achieve the above objectives, the technical scheme is that:
A kind of preparation method of bentonite/flyash composite particles sorbing material, by 70 parts by weight of bentonite, 30 parts by weight
Flyash and 10 parts by weight sodium bicarbonates are sufficiently mixed uniformly, and 30 parts by weight distilled water are added and are uniformly mixing to obtain mixed slurry,
Mixed slurry is aged at room temperature 24 hours, the mixed slurry after ageing is placed in extruder, is squeezed into cylindrical squeeze
Obtained extrusion item is put into spheronizator and is granulated by shaping, when waiting for that each spherolite in spheronizator is uniform in size, closes
Switch takes out the bentonite/flyash composite particles sorbing material for being rolled into spherical shape,
Bentonite/flyash composite particles sorbing material is air-dried into 40min at room temperature, by bentonite/fine coal after air-drying
Grey composite particles sorbing material is put into Muffle furnace, and 80min is roasted at a temperature of 600 DEG C, then stops heating, waits for Muffle furnace certainly
It is taken out after being so cooled to room temperature, bentonite/flyash composite particles sorbing material after being roasted.
A diameter of 3-5mm of bentonite made from the spheronizator/flyash composite particles sorbing material.
Spheronizator will squeeze out a heap and be discharged on the rotation friction plate of spheronizator, squeeze out item and be then dispersed into length when being granulated
Degree is equivalent to the cylinder material of its diameter, and due to the effect of frictional force, these cylinder materials do not stop on rotation friction plate
Ground rolls, and is gradually rolled into spheroidal, forms the spherolite of a plurality of rollings.
Bentonite uses sodium bentonite.
After adopting the above technical scheme, a kind of preparation method of bentonite/flyash composite particles sorbing material of the present invention,
Bentonite/flyash composite particles sorbing material is prepared using extrusion spheronization method, technological process is simple, easy to operate, improves swollen
Moisten the mechanical strength and adsorption activity of soil/flyash composite particles sorbing material.
Specific implementation mode
In order to further explain the technical solution of the present invention, being explained in detail the present invention below by specific embodiment
It states.In the present embodiment, bentonite uses sodium bentonite.
One, preparation method
By the carbon of 300 mesh of the sodium bentonite of 70 parts by weight, 200 mesh, the flyash of 30 parts by weight, 200 mesh and 10 parts by weight
Sour hydrogen sodium point is uniformly mixed, and 30 parts by weight distilled water are added and are uniformly mixing to obtain mixed slurry, and mixed slurry is old at room temperature
Change 24 hours.Mixed slurry after ageing is placed in extruder, which buys from the special limited public affairs of science and technology in Shenzhen Xinyi
Mixed slurry after ageing is passed through the sieve in extruder by department, model E25 low temperature extruders through the fashion of extrusion of screw propulsion
Hole is squeezed into the cylindrical extrusion item of 0.9mm diameters, obtained extrusion item is put into spheronizator and is granulated, this is round as a ball
Machine purchase is from Shenzhen Xinyi spy Science and Technology Ltd., model Mini S spheronizators, specifically, will squeeze out a heap be discharged at it is round as a ball
On the rotation friction plate of machine, squeezes out item and be then dispersed into the cylinder material that length is equivalent to its diameter, due to the work of frictional force
With these cylinder materials ceaselessly roll on rotation friction plate, are gradually rolled into spheroidal, form the ball of a plurality of rollings
Grain turns off the switch when waiting for that each spherolite size in spheronizator is almost the same (i.e. uniform in size), and taking-up is rolled into spherical shape
Bentonite/flyash composite particles sorbing material, a diameter of 3-5mm of bentonite/flyash composite particles sorbing material.
Bentonite/flyash composite particles sorbing material is air-dried into 40min at room temperature, by bentonite/fine coal after air-drying
Grey composite particles sorbing material is put into Muffle furnace, and 80min is roasted at a temperature of 600 DEG C, then stops heating, waits for Muffle furnace certainly
It is taken out after being so cooled to room temperature, bentonite/flyash composite particles sorbing material, i.e. absorbent particles after being roasted, to useless
Water has suction-operated.
Two, performance test
1, mechanical strength test
At room temperature by the bentonite after roasting/flyash composite particles sorbing material, in thermostatic control oscillator vibration with
After the frequency of oscillation concussion 1h of 150r/min, measures particle rate of scattering and disappearing and be less than 1%, by above-mentioned test result it is found that system of the present invention
The high mechanical strength of standby bentonite/flyash composite particles sorbing material, is not easy to disperse, easy to be recycled.
It should be noted that adsorbed the heavy metals such as copper bentonite/flyash composite particles sorbing material can after
It is continuous to be desorbed, and then bentonite/flyash composite particles sorbing material may be reused, the heavy metals such as copper can also be again
It utilizes.Desorption method is the known technology in industry, is not described in detail herein.
The calculating of rate of scattering and disappearing:It weighs a certain amount of absorbent particles and (is denoted as P1), it moves into the conical flask of 50mL, takes in
After 20ml distilled water, with the oscillation frequency 1h of 150r/min in thermostatic control oscillator vibration, then go wash with distilled water
Except powder.Finally wet absorbent particles are put into baking oven, are dried within the scope of 103~105 DEG C, until absorbent particles
Weight no longer changes, and weighs after being cooled to room temperature and (is denoted as P2), the calculation formula of rate of scattering and disappearing P is as follows:
P=(P1-P2)/P1× 100%
Contrast test 1
With cupric (Cu in waste water2+) for 57mg/L, the bentonite clay particle sorbing material prepared using the method for the present invention is (no
Add flyash) adsorption treatment is carried out, adsorption time 360min, copper removal rate is up to 96% or more.But particulate adsorbent material
Rate of scattering and disappearing is up to 48% or more, i.e. mechanical strength is low.
Contrast test 2
With cupric (Cu in waste water2+) for 57mg/L, adsorbed using traditional bentonite powder (non-granulating and forming)
Processing, adsorption time 360min, copper removal rate is up to 97% or more.But treated, and powder largely suspends, it is difficult to it filters, it is long
Sludge is obtained after temporal filtering, that is, is not easily recycled utilization.
2, wastewater treatment is tested
Test 1
With cupric (Cu in waste water2+) for 57mg/L, the bentonite/flyash composite particles prepared using the present invention are adsorbed
Material carries out adsorption treatment, and adsorption time 360min, copper removal rate is up to 96% or more.
Test 2
With leaded (Pb in waste water2+) for 100mg/L, compound of bentonite/flyash being prepared using the method for the present invention
Grain sorbing material carries out adsorption treatment, and adsorption time 120min, lead removal rate is up to 97% or more.
Test 3
With (the Zn containing zinc in waste water2+) for 100mg/L, the bentonite/flyash composite particles prepared using the present invention are inhaled
Enclosure material carries out adsorption treatment, and adsorption time 100min, zinc removal rate is up to 96% or more.
In summary test result illustrates, compared with traditional sorbing material, using the bentonite/fine coal of the invention prepared
Grey composite adsorbing material has both the good and easy to be recycled feature of high mechanical strength, adsorption activity.
A kind of preparation method of bentonite/flyash composite particles sorbing material of the present invention, it is compound to bentonite/flyash
The preparation of particulate adsorbent material done following four in terms of design and arrangement:
(1) adsorbent of the flyash as wastewater treatment is used, it is excellent that existing raw material is cheap and easy to get, industrial operation is simple etc.
Point, achievees the purpose that the treatment of wastes with processes of wastes against one another at the problem of also solving the problem that the environmental pollution and recycling of waste water and dregs, has apparent
Economic benefit and social effect;
(2) addition sodium bicarbonate is as pore-foaming agent, and in roasting process, sodium bicarbonate decomposes the CO generated2Suction can be increased
The porosity and specific surface area of enclosure material, improve the absorption property of material;
(3) granulation or non-granulating and forming by hand, the technique that the present invention uses extrusion spheronization so that bentonite/powder are compared
Coal ash material uniformly mixes, and grain diameter size is controllable, and production efficiency increases substantially;
(4) calcination temperature control both can guarantee that material was well sintered at 600 DEG C, improve mechanical strength, and do not destroy swelling
The hydroxyl structure of soil, does not influence bentonitic absorption property.
In this way, a kind of preparation method of bentonite/flyash composite particles sorbing material, is prepared swollen using extrusion spheronization method
Moisten soil/flyash composite particles sorbing material, technological process is simple, easy to operate, improves bentonite/flyash composite particles and inhales
The mechanical strength and adsorption activity of enclosure material.
The product form and style of above-described embodiment and the non-limiting present invention, the ordinary skill people of any technical field
The appropriate changes or modifications that member does it all should be regarded as the patent category for not departing from the present invention.
Claims (5)
1. a kind of preparation method of bentonite/flyash composite particles sorbing material, it is characterised in that:By 70 parts by weight swellings
Soil, 30 weight parts of fine coal ash and 10 parts by weight sodium bicarbonates are sufficiently mixed uniformly, and 30 parts by weight distilled water are added and stir evenly
To mixed slurry, mixed slurry is aged at room temperature 24 hours, the mixed slurry after ageing is placed in extruder, is squeezed into
Cylindrical extrusion item, obtained extrusion item is put into spheronizator and is granulated, waits for that each spherolite in spheronizator is uniform in size
When, it turns off the switch, takes out the bentonite/flyash composite particles sorbing material for being rolled into spherical shape,
Bentonite/flyash composite particles sorbing material is air-dried into 40min at room temperature, it is after air-drying that bentonite/flyash is multiple
It closes particulate adsorbent material and is put into Muffle furnace, 80min is roasted at a temperature of 600 DEG C, then stop heating, wait for that Muffle furnace is naturally cold
But to taking out after room temperature, bentonite/flyash composite particles sorbing material after being roasted.
2. the preparation method of bentonite as described in claim 1/flyash composite particles sorbing material, it is characterised in that:Institute
State a diameter of 3-5mm of bentonite made from spheronizator/flyash composite particles sorbing material.
3. the preparation method of bentonite as described in claim 1/flyash composite particles sorbing material, it is characterised in that:Rolling
Circular knitting machine will squeeze out a heap and be discharged on the rotation friction plate of spheronizator, extrusion item is then dispersed into length and is equivalent to it when being granulated
The cylinder material of diameter, due to the effect of frictional force, these cylinder materials ceaselessly roll on rotation friction plate, gradually
It is rolled into spheroidal, forms the spherolite of a plurality of rollings.
4. the preparation method of bentonite as described in claim 1/flyash composite particles sorbing material, it is characterised in that:It is swollen
Profit soil uses sodium bentonite.
5. the preparation method of bentonite as described in claim 1/flyash composite particles sorbing material, it is characterised in that:Institute
Extruder is bought from Shenzhen Xinyi spy Science and Technology Ltd., model E25 low temperature extruders;Spheronizator purchase used
From Shenzhen Xinyi spy Science and Technology Ltd., model Mini S spheronizators.
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Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN112387247A (en) * | 2019-08-19 | 2021-02-23 | 万华化学集团股份有限公司 | Modified fly ash adsorbent and preparation method thereof, and trimethylamine adsorption method |
CN114618423A (en) * | 2022-03-01 | 2022-06-14 | 湖北富邦科技股份有限公司 | Preparation method of porous structure composite adsorption material |
CN114682209A (en) * | 2020-12-25 | 2022-07-01 | 柳州柳晶环保科技有限公司 | Method for preparing adsorbing material by using coal dust-containing casting dust and adsorbing material |
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CN101678314A (en) * | 2007-03-08 | 2010-03-24 | 普莱克斯技术有限公司 | High rate and high crush-strength adsorbents |
CN102114401A (en) * | 2009-12-31 | 2011-07-06 | 中国科学院生态环境研究中心 | Arsenic removal adsorbent and preparation method thereof |
CN101829608A (en) * | 2010-06-11 | 2010-09-15 | 天津大学 | Preparation method and application of ammonium ion exchange material |
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Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN112387247A (en) * | 2019-08-19 | 2021-02-23 | 万华化学集团股份有限公司 | Modified fly ash adsorbent and preparation method thereof, and trimethylamine adsorption method |
CN112387247B (en) * | 2019-08-19 | 2022-08-02 | 万华化学集团股份有限公司 | Modified fly ash adsorbent and preparation method thereof, and trimethylamine adsorption method |
CN114682209A (en) * | 2020-12-25 | 2022-07-01 | 柳州柳晶环保科技有限公司 | Method for preparing adsorbing material by using coal dust-containing casting dust and adsorbing material |
CN114618423A (en) * | 2022-03-01 | 2022-06-14 | 湖北富邦科技股份有限公司 | Preparation method of porous structure composite adsorption material |
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Application publication date: 20180928 |