CN105195084A - Preparation method for modified activated aluminum oxide for removing fluorine ions in coal bed gas produced water - Google Patents

Preparation method for modified activated aluminum oxide for removing fluorine ions in coal bed gas produced water Download PDF

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Publication number
CN105195084A
CN105195084A CN201410286967.0A CN201410286967A CN105195084A CN 105195084 A CN105195084 A CN 105195084A CN 201410286967 A CN201410286967 A CN 201410286967A CN 105195084 A CN105195084 A CN 105195084A
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China
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factor
aluminum oxide
activated aluminum
concentration
activated alumina
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Inventor
胡正义
朱晓琦
黄丽娟
琚宜文
吴建光
熊德华
李忠城
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University of Chinese Academy of Sciences
China United Coalbed Methane Corp Ltd
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University of Chinese Academy of Sciences
China United Coalbed Methane Corp Ltd
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Abstract

The invention relates to a preparation method for a modified activated aluminum oxide for removing fluorine ions in coal bed gas produced water. The orthogonal method is utilized for determining a preferred scheme. The preferred modification method comprises the following steps that 1, 50g of activated aluminum oxide particles are placed into 100 mL of a NaOH solution with the concentration being 0.05 mol/L for oscillation at 150 rpm for 1 h at the room temperature of 25 DEG C; the activated aluminum oxide particles are taken out and then washed with purified water 8-10 times till washing water is limpid and colorless, so that the pH shows that the activated aluminum oxide particles are neutral, and then the activated aluminum oxide particles are dried at the temperature of 105 DEG C for 20 h; 2, dried activated aluminum oxide particles are placed into 100 mL of a KAl(SO4)2 solution with the concentration being 5% for oscillation at 150 rpm for 4 h at the room temperature of 25 DEG C; the activated aluminum oxide particles are taken out and washed with purified water 8-10 times till the washing water is limpid and colorless and has no suspended matter, and then the activated aluminum oxide particles are dried at the temperature of 105 DEG C for 20 h; 3, the dried activated aluminum oxide particles are placed into a microwave oven for high-fired heating for 15 min. The modification method is fast and convenient to operate and good in effect and has the certain reference for industrial production.

Description

A kind of preparation method of the modified activated aluminum oxide for removing fluorine ion in coal bed gas product water
Technical field
The invention belongs to the optimisation technique field of de-fluoridation adsorbent in coal bed gas product water treatment procedure.This preparation method is convenient, and defluorination effect is good, with low cost, and exploitativeness is strong, is applicable to laboratory research, possesses certain referentiability to exploring commercial production conditions further.
Background technology
Coal seam gas field produced water is except having the feature such as high salinity, high salinity, sometimes the fluorine ion also containing high concentration, the Fluorine of Drinking Water ion critical value (1.5mgL that limit value and WHO beyond defined in China " agricultural irrigation water quality standard GB5084-2005 " specify -1).Therefore, the direct discharge of high fluorine coal bed gas product water or use can have an impact to the agricultural production of locality, even can polluted drinking water source and underground water.Activated alumina is the sewage de-fluoridation adsorbent of extensive use.Common industrial activated alumina is except fluorine finite capacity.But, can greatly improve its Fluoride-Absorption Capacity through modification someway, for removing the fluorine ion in waste water.
Microwave modification activated alumina is utilized to be proved to be a kind of feasible method.Also adopt microwave method to be immersed in by activated alumina in sodium chloride solution before this seminar and carry out modification (number of patent application 201110370230.3), the adsorption effect of activated alumina to fluorine ion can be improved.On this basis, the present invention, in conjunction with two kinds of method of modifying, adopts Orthogonal Design Method Design experiment to investigate the impact of various factor pair modified activated aluminum oxide, explores optimum modified condition, to obtain the good activated alumina of absorption property, thus improve the adsorption capacity to coal bed gas product fluorine in wastewater.
Summary of the invention
The object of the invention is on the impact of activated alumina modification, to provide the method for modifying of a kind of simple operation, excellent effect, to improve the ability of fluorine ion in its adsorbed water by investigating four factors in modifying process.
The modification procedure of activated alumina is as follows:
50g activated alumina particle is placed in the certain density NaOH solution of 100mL (factor A) by 1.Under room temperature 25 DEG C of conditions, with 150rpm vibration 1h.After taking-up, with purified rinse water 8-10 time, until flushing water is limpid colourless, makes pH be neutral, then at 105 DEG C, dry 20h;
The activated alumina particle of oven dry is placed in the certain density KAl (SO of 100mL by 2 4) 2in solution (factor B), room temperature 25 DEG C, 150rpm vibrates a period of time (factor C).After taking-up, with purified rinse water 8-10 time, until the limpid colourless no suspended substance of flushing water, then at 105 DEG C, dry 20h;
The activated alumina particle of oven dry is placed in high fire heating a period of time (factor D) of micro-wave oven by 3.
Obtaining best modified condition is by experiment: factor A and NaOH solution concentration are 0.05mol/L; Factor B and KAl (SO 4) 2solution concentration is 5%; Namely factor C uses KAl (SO 4) 2the time of solution vibration is 4h; Factor D and heating using microwave are 15min.
Accompanying drawing illustrates:
Fig. 1 is first experimental result;
Fig. 2 is second batch experimental result;
Fig. 3 is the preparation method of modified activated aluminum oxide.
Specific embodiments:
Select L 9(3 4) orthogonal arrage (four factors, three levels, 9 times experiment) carry out experiment.
Modified activated aluminum oxide experiment is carried out in two batches.First experiment determines that factor on a large scale, and second batch experiment locking factor among a small circle.
Embodiment 1
First experiment 1) number A 1b 1c 1d 2: 50g activated alumina particle is placed in the NaOH solution (factor A) that 100mL concentration is 0.1mol/L.Under room temperature 25 DEG C of conditions, with 150rpm vibration 1h.After taking-up, with purified rinse water 8-10 time, until flushing water is limpid colourless, makes pH be neutral, then at 105 DEG C, dry 20h; The activated alumina particle of oven dry is placed in the KAl (SO that 100mL concentration is 1% 4) 2in solution (factor B), under room temperature 25 DEG C of conditions, with 150rpm vibration 1h (factor C).After taking-up, with purified rinse water 8-10 time, until the limpid colourless no suspended substance of flushing water, then at 105 DEG C, dry 20h.Finally, the activated alumina particle of oven dry is placed in high fire heating 15min (factor D) of micro-wave oven.
Embodiment 2
First experiment 2) number A 1b 2c 3d 1: step is with embodiment 1, and wherein NaOH solution (factor A) concentration is 0.1mol/L; KAl (SO 4) 2solution (factor B) concentration is 3%; Duration of oscillation is 7h (factor C); In micro-wave oven, the high fire heat time is 5min (factor D).
Embodiment 3
First experiment 3) number A 1b 3c 2d 3: step is with embodiment 1, and wherein NaOH solution (factor A) concentration is 0.1mol/L; KAl (SO 4) 2solution (factor B) concentration is 5%; Duration of oscillation is 4h (factor C); In micro-wave oven, the high fire heat time is 20min (factor D).
Embodiment 4
First experiment 4) number A 2b 1c 3d 3: step is with embodiment 1, and wherein NaOH solution (factor A) concentration is 0.5mol/L; KAl (SO 4) 2solution (factor B) concentration is 1%; Duration of oscillation is 7h (factor C); In micro-wave oven, the high fire heat time is 20min (factor D).
Embodiment 5
First experiment 5) number A 2b 2c 2d 2: step is with embodiment 1, and wherein NaOH solution (factor A) concentration is 0.5mol/L; KAl (SO 4) 2solution (factor B) concentration is 3%; Duration of oscillation is 4h (factor C); In micro-wave oven, the high fire heat time is 15min (factor D).
Embodiment 6
First experiment 6) number A 2b 3c 1d 1: step is with embodiment 1, and wherein NaOH solution (factor A) concentration is 0.5mol/L; KAl (SO 4) 2solution (factor B) concentration is 5%; Duration of oscillation is 1h (factor C); In micro-wave oven, the high fire heat time is 5min (factor D).
Embodiment 7
First experiment 7) number A 3b 1c 2d 1: step is with embodiment 1, and wherein NaOH solution (factor A) concentration is 1mol/L; KAl (SO 4) 2solution (factor B) concentration is 1%; Duration of oscillation is 4h (factor C); In micro-wave oven, the high fire heat time is 5min (factor D).
Embodiment 8
First experiment 8) number A 3b 2c 1d 3: step is with embodiment 1, and wherein NaOH solution (factor A) concentration is 1mol/L; KAl (SO 4) 2solution (factor B) concentration is 3%; Duration of oscillation is 1h (factor C); In micro-wave oven, the high fire heat time is 20min (factor D).
Embodiment 9
First experiment 9) number A 3b 3c 3d 2: step is with embodiment 1, and wherein NaOH solution (factor A) concentration is 1mol/L; KAl (SO 4) 2solution (factor B) concentration is 5%; Duration of oscillation is 7h (factor C); In micro-wave oven, the high fire heat time is 15min (factor D).
Embodiment 10
Second batch experiment 1) number A 1b 1c 1: 50g activated alumina particle is placed in the NaOH solution (factor A) that 100mL concentration is 0.01mol/L.Under room temperature 25 DEG C of conditions, with 150rpm vibration 1h.After taking-up, with purified rinse water 8-10 time, until flushing water is limpid colourless, pH, in neutral, then dries 20h at 105 DEG C; The activated alumina particle of oven dry is placed in the KAl (SO that 100mL concentration is 4.5% 4) 2in solution (factor B), under room temperature 25 DEG C of conditions, with 150rpm vibration 3h (factor C).After taking-up, with purified rinse water 8-10 time, until the limpid colourless no suspended substance of flushing water, then at 105 DEG C, dry 20h.Finally, the activated alumina particle of oven dry is placed in micro-wave oven high fire heating 15min.
Embodiment 11
Second batch experiment 2) number A 1b 2c 3: step is with embodiment 10, and wherein NaOH solution (factor A) concentration is 0.01mol/L; KAl (SO 4) 2solution (factor B) concentration is 5%; Duration of oscillation is 5h (factor C).
Embodiment 12
Second batch experiment 3) number A 1b 3c 2: step is with embodiment 10, and wherein NaOH solution (factor A) concentration is 0.01mol/L; KAl (SO 4) 2solution (factor B) concentration is 5.5%; Duration of oscillation is 4h (factor C).
Embodiment 13
Second batch experiment 4) number A 2b 1c 3: step is with embodiment 10, and wherein NaOH solution (factor A) concentration is 0.05mol/L; KAl (SO 4) 2solution (factor B) concentration is 4.5%; Duration of oscillation is 5h (factor C).
Embodiment 14
Second batch experiment 5) number A 2b 2c 2: step is with embodiment 10, and wherein NaOH solution (factor A) concentration is 0.05mol/L; KAl (SO 4) 2solution (factor B) concentration is 5%; Duration of oscillation is 4h (factor C).
Embodiment 15
Second batch experiment 6) number A 2b 3c 1: step is with embodiment 10, and wherein NaOH solution (factor A) concentration is 0.05mol/L; KAl (SO 4) 2solution (factor B) concentration is 5.5%; Duration of oscillation is 5h (factor C).
Embodiment 16
Second batch experiment 7) number A 3b 1c 2: step is with embodiment 10, and wherein NaOH solution (factor A) concentration is 0.1mol/L; KAl (SO 4) 2solution (factor B) concentration is 4.5%; Duration of oscillation is 4h (factor C).
Embodiment 17
Second batch experiment 8) number A 3b 2c 1: step is with embodiment 10, and wherein NaOH solution (factor A) concentration is 0.1mol/L; KAl (SO 4) 2solution (factor B) concentration is 5%; Duration of oscillation is 3h (factor C).
Embodiment 18
Second batch experiment 9) number A 3b 3c 3: step is with embodiment 10, and wherein NaOH solution (factor A) concentration is 0.1mol/L; KAl (SO 4) 2solution (factor B) concentration is 5.5%; Duration of oscillation is 5h (factor C).
The static experiment of fluorine ion in activated alumina adsorbed water: with embodiment 1-9 (first experiment), the modified activated aluminum oxide that embodiment 10-18 (second batch experiment) prepares carries out adsorption experiment.
Specific embodiments is described below:
1 experiment material: the fluorinated water of modified activated aluminum oxide, 10mg/L is (with F -meter, by the KF standard reserving solution of 1000ppm, dilution obtain), TISABI (230mL acetic acid, 232gNaCl, 16gCDTA and 150gNaOH are settled to 4L, and with 5mol/LNaOH regulate pH be 5.25)
2 experimental procedures: take 2g activated alumina, are placed in the plastic bottle of 200mL, and add the fluorinated water (in F) that 100mL concentration is 10mg/L, after being placed in shaking table 25 DEG C of constant temperature oscillation 3h, sampling and measuring is F concentration wherein.Calculated activity aluminium oxide is to the adsorbance q of fluorine according to the following formula t(mg/kg):
q t＝(C 0-C t)×V/m
Wherein, C 0---F concentration in solution before reaction is 10mg/L
C t---F in t solution -concentration, unit is mg/L
V---liquor capacity is 0.1L
M---adsorbent mass is 0.001kg
Three kinds of position levels of factor A, B, C, D are listed by table 1 respectively.According to L 9(3 4) orthogonal arrage, altogether needs nine experiments, modified effect of first experiment is as shown in table 2, and accompanying drawing 1 is shown in interpretation of result.
Carry out analysis to the result of first experiment to find, the 2nd) number test A 1b 2c 3d 1result is best, and the 3rd) number test A 1b 3c 2d 3result is taken second place.
Find that this test " NaOH concentration " is that consumption selects inclined factor from accompanying drawing 1, can courageously reduce NaOH concentration, to obtain better activated alumina modification result.
KAl (SO 4) 2concentration is higher, and the adsorbance of activated alumina to F is larger.But, 20 DEG C time, in 100g water, 5.9gKAl (SO can only be dissolved 4) 2.Consider in practical application, use heater means possibility little, think that 5% for KAl (SO 4) 2optium concentration.
Adsorption effect increases along with the prolongation of concussion time, but time expand affects speed of production.The adsorbance of 4h of vibrating in this experiment is maximum can reach 645mg/kg, and shaking 7h is then 667mg/kg, is not significantly improved.Therefore, best duration of oscillation is 4h.
The microwave time is the minimum factor of extreme difference R, and its scope is not estimated partially.So good position level is D 2=15min, namely the microwave time is 15min.
By first experiment, determine that the optimum condition of factor D is 15min.Therefore, in second batch experiment, no longer consider the change of microwave heating time, unification is fixed as 15min, and by the range shorter of factor A, B, C.
Three kinds of position levels of factor A, B, C are listed by table 3 respectively.According to L 9(3 4) orthogonal arrage, altogether needs nine experiments, the modified effect of second batch experiment is as shown in table 4, and accompanying drawing 2 is shown in interpretation of result.
By table 4 and accompanying drawing 2, think that second batch experiment can determine embodiment 14 (i.e. second batch experiment 5) number) be optimal selection, the design parameter of factor is as shown in table 5.
Modified activated aluminum oxide is preparation method be specially:
1) 50g activated alumina particle is placed in the NaOH solution that 100mL concentration is 0.05mol/L.Under room temperature 25 DEG C of conditions, with 150rpm vibration 1h.After taking-up, with purified rinse water 8-10 time, until flushing water is limpid colourless, makes pH be neutral, then at 105 DEG C, dry 20h;
2) activated alumina particle of oven dry is placed in the KAl (SO that 100mL concentration is 5% 4) 2in solution, under room temperature 25 DEG C of conditions, with 150rpm vibration 4h.After taking-up, with purified rinse water 8-10 time, until the limpid colourless no suspended substance of flushing water, then at 105 DEG C, dry 20h;
3) activated alumina particle of oven dry is placed in micro-wave oven high fire heating 15min.
The optimum seeking table of first experiment of table 1
Table 2 first orthogonal experiment scheme and interpretation of result
The optimum seeking table of table 3 second batch experiment
Table 4 second batch orthogonal experiment scheme and interpretation of result
Table 5 each factor optimal selection parameter
In conjunction with further description of test effect of the present invention:
By the activated alumina through above-mentioned optimum factor modification for the treatment of the F in the coal bed gas product waste water of Yang Jia valley, Liulin County, Lvliang City, Shanxi Province.F content in output waste water is 7.65mg/L.100mL coal bed gas product waste water is added in 200mL plastic bottle.The activated alumina taking 2g modified is placed in plastic bottle, then is put in shaking table by plastic bottle, after 25 DEG C of constant temperature oscillation 3h, and its F concentration of sampling and measuring.Residual F concentration in analysis result display waste water is 0.45mg/L, reaches " agricultural irrigation water quality standard (GB5084-2005) " and " livestock and poultry water quality standard for drinking water (NY5027-2008) ".Modified activated alumina is 94.1%, F adsorbance to the clearance of F is 360mg/kg, is significantly higher than the 145mg/L of former activated alumina.

Claims (4)

1. modified activated aluminum oxide is for improving an ability for its Adsorption of fluoride ion in coal bed gas product waste water, it is characterized in that its modification procedure is: 1. 50g activated alumina particle is placed in the certain density NaOH solution of 100mL (factor A).Under room temperature 25 DEG C of conditions, with 150rpm vibration 1h.After taking-up, with purified rinse water 8-10 time, until flushing water is limpid colourless, makes pH be neutral, then under 105 DEG C of conditions, dry 20h; 2. the activated alumina particle after baking is placed in the certain density KAl (SO of 100mL 4) 2in solution (factor B).Under room temperature 25 DEG C of conditions, vibrate a period of time (factor C) with 150rpm.After taking-up, with purified rinse water 8-10 time, until the limpid colourless no suspended substance of flushing water, then at 105 DEG C, dry 20h; 3. the activated alumina particle after baking is placed in high fire heating a period of time (factor D) of micro-wave oven.
2. the method for modified activated aluminum oxide according to claim 1, is characterized in that the optimal parameter for determining factor A, B, C, D, utilizing L 9(3 4) orthogonal arrage, design two batches of experiments.
3. the method for modified activated aluminum oxide according to claim 1, is characterized in that the KJ23C-AN2 that the micro-wave oven model that heating using microwave step uses is U.S..Instrument design parameter is: input rated power 1300W, microwave output power 800W, microwave operational frequencies 2450MHz, roasting power is 1000W.Microwave height fire screen is adopted in the present invention.
4. the method for modifying according to right 1,2,3, is characterized in that method for optimizing is: 1. 50g activated alumina particle is placed in the NaOH solution that 100mL concentration is 0.05mol/L.Under room temperature 25 DEG C of conditions, with 150rpm vibration 1h.After taking-up, with purified rinse water 8-10 time, until flushing water is limpid colourless, makes pH be neutral, then at 105 DEG C, dry 20h; 2. the activated alumina particle of oven dry is placed in the KAl (SO that 100mL concentration is 5% 4) 2in solution.Under room temperature 25 DEG C of conditions, with 150rpm vibration 4h.After taking-up, with purified rinse water 8-10 time, until the limpid colourless no suspended substance of flushing water, then at 105 DEG C, dry 20h; 3. the activated alumina particle after baking is placed in micro-wave oven high fire heating 15min.
CN201410286967.0A 2014-06-25 2014-06-25 Preparation method for modified activated aluminum oxide for removing fluorine ions in coal bed gas produced water Pending CN105195084A (en)

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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105858783A (en) * 2016-04-18 2016-08-17 北京化工大学 Application of nanometer flaky aluminum oxide to removal of fluorine ions from water
CN106587246A (en) * 2016-11-29 2017-04-26 洛阳建龙微纳新材料股份有限公司 Application of modified activated alumina in wastewater defluorination
CN108341440A (en) * 2018-03-02 2018-07-31 北京利华消防工程有限公司 The method of water treatment agent, preparation method and water treatment agent processing fire demand water

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105858783A (en) * 2016-04-18 2016-08-17 北京化工大学 Application of nanometer flaky aluminum oxide to removal of fluorine ions from water
CN106587246A (en) * 2016-11-29 2017-04-26 洛阳建龙微纳新材料股份有限公司 Application of modified activated alumina in wastewater defluorination
CN108341440A (en) * 2018-03-02 2018-07-31 北京利华消防工程有限公司 The method of water treatment agent, preparation method and water treatment agent processing fire demand water
CN108341440B (en) * 2018-03-02 2021-02-23 北京利华消防工程有限公司 Water treatment agent, preparation method and method for treating fire-fighting water by using water treatment agent

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Application publication date: 20151230