CN101564684A - Method for preparing transitional metal ion Co modified adsorbent for purifying low-concentration phosphine - Google Patents

Method for preparing transitional metal ion Co modified adsorbent for purifying low-concentration phosphine Download PDF

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Publication number
CN101564684A
CN101564684A CNA2009100945024A CN200910094502A CN101564684A CN 101564684 A CN101564684 A CN 101564684A CN A2009100945024 A CNA2009100945024 A CN A2009100945024A CN 200910094502 A CN200910094502 A CN 200910094502A CN 101564684 A CN101564684 A CN 101564684A
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carrier
adsorbent
adsorption
phosphine
under
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唐晓龙
余琼粉
易红宏
宁平
杨丽萍
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Kunming University of Science and Technology
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Kunming University of Science and Technology
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Abstract

The invention relates to a method for preparing transitional metal ion Co modified adsorbent which is used for purifying low-concentration phosphine and mainly used for removing low-concentration phosphine in industrial production tail gas, belonging to the technical field of application of adsorption separation technique in atmospheric pollution purification. The method comprises the following steps of: (1) carrying out ultrasonic washing and drying treatment to an adsorbing material carrier until a constant-weight carrier is formed; (2) selecting a soluble cobalt salt to carry out ultrasonic immersing modification to the pretreated adsorbent carrier; (3) washing and drying the immersed adsorbent carrier; and (4) roasting the dried adsorbent carrier, and reducing the temperature to room temperature. The adsorbent prepared in the invention is unnecessary to add accelerating agents, such as noble metals or high-contamination heavy metals and the like; when the adsorbent is used for adsorbing waste gas containing phosphine, the adsorption is conducted by the surface of the modified adsorbent; waste gas dephophorization can be realized after the adsorption is saturated; and the adsorption activity is higher within in a certain temperature range.

Description

The transitional metal ion Co modified adsorbent preparation method who is used for purifying low-concentration phosphine
One, technical field
The present invention relates to a kind of transitional metal ion Co modified adsorbent preparation method who is used for purifying low-concentration phosphine, be mainly used in the low-concentration hydrogen phosphide that removes in the industrial production tail gas, belong to adsorption separation technology and be applied to atmosphere pollution purification techniques field.
Two, technical background
All contain certain density phosphine gas in the gas that is produced in the processes such as yellow phosphorus preparation, the preparation of magnesium powder, sodium hypophosphite production, acetylene production, feed fermentation, grain are fumigated, semi-conductor industry production.Phosphine gas in the tail gas directly is discharged in the atmosphere can cause environmental pollution, is detrimental to health.Be used if tail gas containing phosphine especially is rich in the yellow phosphoric tail gas of CO, then can make catalyst poisoning, seriously restricted the recycling of refuse because of the existence of phosphine gas.Phosphine gas is included in the U.S. EPA emphasis control air in 190 kinds of noxious pollutant lists, and the purifying problem of hydrogen phosphide becomes increasingly conspicuous in the visible industrial waste gas.
At present, the method for handling phosphine waste gas both at home and abroad is divided into dry method and wet method two big classes.Dry method is to utilize the reproducibility and the combustibility of hydrogen phosphide, removes hydrogen phosphide with solid oxidizer or adsorbent, or directly burning.Wet method then is the difference of the Dephosphorising agent that acts on by it, is divided into redox absorption process and liquid phase catalytic oxidation again.
Firing method belongs to traditional processing method, and present domestic most sodium hypophosphite manufacturer all adopts this process to handle hydrogen phosphide in tail gas.This method technological process is simple, realize easily, but this method is only applicable to the processing of high concentration phosphatization hydrogen, and still has part hydrogen phosphide and phosphoric acid acid mist enter and cause secondary pollution in the atmosphere in processing procedure.In the yellow phosphoric tail gas traditional treatment method, also be to utilize this method at high temperature with hydrogen phosphide and other pollutant oxidation, purification, but this method can not reclaim the Co in the yellow phosphoric tail gas, energy waste is huge, and in " Yunnan Province's phosphorous chemical industry structural adjustment in 2008~2012 years job guide suggestion ", propose, make that comprehensive utilization of resources obtains remarkable effect in the phosphorus production, the phosphorus furnace exhaust gas utilization rate of 10,000 tons and above device will surpass 90%, and extinguishes " torch ".Therefore it is very urgent to seek a kind of suitable method purifying hydrogen phosphide waste gas.
The redox absorption process is to utilize the reproducibility and the solution reaction that contains oxidant (as clorox, potassium permanganate, sulfuric acid, hydrogen peroxide, phosphoric acid etc.) of hydrogen phosphide, realize the purification of hydrogen phosphide, need to consume oxidant in this method, dephosphorization efficient and oxidant concentration are closely related, and oxidant concentration descends very fast in the absorption reaction process, thereby existing operating cost higher, dephosphorization efficient easily fluctuates, shortcomings such as device poor operability.Chinese patent CN 85105317 (publication number) has reported the method for eccysis hydrogen phosphide from acetylene gas, this method is used 70% phosphoric acid solution, but this method flow process complexity, gas need pass through the preliminary treatment of milk of lime scrubbing tower, also need consume pure oxygen washing acid is regenerated, and the residual concentration of not mentioned washing back hydrogen phosphide.
Chinese patent CN 1398658A (publication number) discloses a kind of method that adopts fixed bed catalytic oxidation to purify yellow phosphoric tail gas, has developed catalyst series and has been used for catalysis absorption PH 3Impurity, its principle is to utilize PH 3Strong reducing property and the active component on active carbon reaction generate P 2O 3And P 2O 5, and utilize P 2O 3And P 2O 5Adsorbance much larger than PH 3These characteristics realize the deep purifying of yellow phosphoric tail gas, and shortcoming is to need strict oxygen or the air that quantitatively adds in yellow phosphoric tail gas, has strengthened operation, control difficulty, and because P 2O 3And P 2O 5Active carbon make absorption saturated at the high adsorption capacity on the active carbon after is difficult for regeneration, promptly exists phosphorous active carbon to need problems such as subsequent treatment.
It is active component that United States Patent (USP) numbering US 5182088 discloses with copper commonly used, zinc oxide, add promoter such as AgO, HgO again, chemosorbent with the coprecipitation preparation, chemosorbent has the adsorption capacity of remarkable lifting, but, certainly will increase cost of manufacture and the disposal cost of fertilizer in the future owing to need to add noble metal (AgO) or high pollution heavy metal promoter such as (HgO, CdO).Chinese patent CN1565706A (publication number) disclose in the oxide with copper, zinc, magnesium and manganese at least a as active constituent loading to the carrier components that is selected from the group that aluminium, silicon and titanyl compound formed, a kind of cleaning agent that is used for the chemisorbed phosphine gas is provided.Chemisorbed is removed the hydrogen phosphide in semiconductor factory and the photoelectricity factory processing procedure waste gas under this method realization normal temperature, but regeneration or other processing modes after not mentioned cleaning agent lost efficacy are transferred to not realization purification completely the solid phase but just will pollute in essence from gas phase.Chinese patent CN 1345619A (publication number) has announced a kind of method of pressure and temperature varying adsorption cleaning yellow phosphoric tail gas, and this method is to utilize under different pressures and temperature adsorbent that the difference of hydrogen phosphide adsorption capacity is realized isolation of purified.In the pressure and temperature varying adsorption process, the regeneration of dephosphorization effect and adsorbent is studied, experiment effect is better, but regenerative process is to make the hydrogen phosphide component oxidized with the nitrogen or a part of purified gas that contain oxygen 0.01%~5% simultaneously as regeneration gas, can not realize the phosphine gas own resourcesization.
Therefore, along with the appearance and the generation of phosphine containing waste gas of national energy-saving and emission-reduction policy are increasing, research and development simple and high-efficient low concentration phosphine waste gas purification method is taken into account the recovery of phosphine gas resource simultaneously, has important practical significance.
Three, summary of the invention
The object of the present invention is to provide a kind of transitional metal ion Co modified adsorbent preparation method and application that is used for purifying low-concentration phosphine, and need not add noble metal (AgO) or high pollution heavy metal promoter such as (HgO, CdO).
Another object of the present invention is to provide the adsorbent that is applicable to purifying low-concentration phosphine gas that has than high-adsorption-capacity, and use the active component of low concentration.
In order to realize the invention described above purpose, this case takes the lead in using transition metal Co ion as active component, is carrier with active carbon, molecular sieve, NACF etc., adopts immersion process for preparing gained adsorbent.
Modified adsorbent preparation method of the present invention comprises the steps:
(1) the sorbing material carrier is carried out supersound washing and dry the processing, up to being processed into the constant weight carrier;
(2) select a kind of solubility cobalt salt that above-mentioned pretreated adsorbing agent carrier is carried out the ultrasonic immersing modification;
(3) to impregnated adsorbing agent carrier flushing, the dry processing;
(4) dried adsorbing agent carrier is carried out roasting, reduce to room temperature again.
The concrete preparation method of modified adsorbent of the present invention is as follows:
(1) the sorbing material carrier is carried out supersound washing after, freeze-day with constant temperature 12~30h under 85~150 ℃ of temperature conditions is cooled to room temperature naturally under 0.1MPa vacuum;
(2) with the solubility cobalt salt to the modification of sorbing material carrier impregnation in, ultrasonic immersing 0.5~2h, the molar concentration that contains cobalt ions in the active component aqueous solution is 0.01~1mol/L;
(3) impregnated adsorbing agent carrier is adopted deionized water rinsing, then dry 12~30h under 85~150 ℃ of temperature;
(4) dried adsorbing agent carrier is at 200~600 ℃ of roasting temperature 2~8h, is cooled to room temperature then under 0.1MPa vacuum naturally.
The above-mentioned sorbing material carrier of the present invention adopts any in active carbon, molecular sieve and the NACF; Described solubility cobalt salt can the selective chlorination cobalt, in cobalt nitrate, cobaltous sulfate and the cobalt acetate any.
The present invention has following advantage and effect: transition metal Co ion modification adsorbent provided by the invention, owing to be that load has the active component cobalt salt on conventional adsorbent, so when the Co ion modification adsorbents adsorb with invention contains the waste gas of hydrogen phosphide, adsorb by the modified adsorbent surface, after treating that absorption reaches capacity, can realize the waste gas dephosphorization, and in 20 ℃~90 ℃ temperature range, all have higher adsorption activity, thereby the invention of this adsorbent provides a kind of simple and easy to do approach for the purification of phosphine waste gas undoubtedly.
Four, the specific embodiment
Embodiment 1:
(1) a certain amount of absorbent charcoal carrier is placed on after with the deionized water supersound washing in the thermostatic drying chamber dry, at 110 ℃ of following freeze-day with constant temperature 24h, take out then and be positioned in the vacuum desiccator, under 0.1MPa vacuum, be cooled to room temperature naturally, taking-up is weighed and record data, repeats above step until the absorbent charcoal carrier constant weight;
(2) (1) step gained absorbent charcoal carrier being immersed molar concentration is the cobalt chloride (CoCl of 0.2mol/L 2) in the aqueous solution, 20 ℃ of following ultrasonic immersing 0.5h;
(3) will rinse well with deionized water through the absorbent charcoal carrier of (2) step dipping, put into thermostatic drying chamber dry 24h under 110 ℃ afterwards;
(4) will put into the Muffle furnace roasting through the dry good absorbent charcoal carrier of (3) step, at 400 ℃ of following roasting 6h, take out then and be positioned in the vacuum desiccator, under 0.1MPa vacuum, be cooled to room temperature naturally, get final product low-concentration hydrogen phosphide purification of the present invention with transition metal Co ion modification acticarbon.
When the Co ion modification acticarbon absorption with invention contained the waste gas of hydrogen phosphide, the adsorption process condition was: adsorbent 11.50g; Absorber inlet gas composition (volume ratio) PH 30.999%, nitrogen is carrier gas; The adsorption isotherm data utilize volumetric method to obtain, and test result is as shown in table 1.
Embodiment 2:
(1) a certain amount of molecular sieve carrier is placed on after with the deionized water supersound washing in the thermostatic drying chamber dry, freeze-day with constant temperature 24h under 110 ℃ of temperature, take out then and be positioned in the vacuum desiccator, under 0.1MPa vacuum, be cooled to room temperature naturally, taking-up is weighed and record data, repeats above step until the molecular sieve carrier constant weight;
(2) (1) step gained molecular sieve carrier being immersed molar concentration is the cobalt chloride (CoCl of 0.2mol/L 2) in the aqueous solution, 20 ℃ of following ultrasonic immersing 0.5h;
(3) will rinse well with deionized water through the molecular sieve carrier of (2) step dipping, put into thermostatic drying chamber dry 24h under 110 ℃ afterwards;
(4) will put into the Muffle furnace roasting through the dry good molecular sieve carrier of (3) step, at 400 ℃ of following roasting 6h, take out then and be positioned in the vacuum desiccator, under 0.1MPa vacuum, be cooled to room temperature naturally, get final product low-concentration hydrogen phosphide purification of the present invention with transition metal Co ion modification adsorbent of molecular sieve.
When the Co ion modification adsorbent of molecular sieve absorption with invention contained the waste gas of hydrogen phosphide, the adsorption process condition was: adsorbent 11.50g; Absorber inlet gas composition (volume ratio) PH 30.999%, nitrogen is carrier gas; The adsorption isotherm data utilize volumetric method to obtain, and test result is as shown in table 1.
Embodiment 3:
(1) a certain amount of NACF carrier is placed on after with the deionized water supersound washing in the thermostatic drying chamber dry, freeze-day with constant temperature 24h under 110 ℃ of temperature, take out then and be positioned in the vacuum desiccator, under 0.1MPa vacuum, be cooled to room temperature naturally, taking-up is weighed and record data, repeats above step until the absorbent charcoal carrier constant weight;
(2) (1) step gained NACF carrier being immersed molar concentration is the cobalt chloride (CoCl of 0.2mol/L 2) in the aqueous solution, 20 ℃ of following ultrasonic immersing 0.5h;
(3) will rinse well with deionized water through the NACF carrier of (2) step dipping, put into thermostatic drying chamber dry 24h under 110 ℃ afterwards;
(4) will put into the Muffle furnace roasting through the dry good NACF carrier of (3) step, at 400 ℃ of following roasting 6h, take out then and be positioned in the vacuum desiccator, under 0.1MPa vacuum, be cooled to room temperature naturally, get final product low-concentration hydrogen phosphide purification of the present invention with transition metal Co ion modification activated carbon fiber adsorbing substance.
When the Co ion modification activated carbon fiber adsorbing substance absorption with invention contained the waste gas of hydrogen phosphide, the adsorption process condition was: adsorbent 1.5g; Absorber inlet gas composition (volume ratio) PH 30.999%, nitrogen is carrier gas; The adsorption isotherm data utilize volumetric method to obtain, and test result is as shown in table 1.
Embodiment 4:
(1) a certain amount of NACF carrier is placed on after with the deionized water supersound washing in the thermostatic drying chamber dry, freeze-day with constant temperature 24h under 110 ℃ of temperature, take out then and be positioned in the vacuum desiccator, under 0.1MPa vacuum, be cooled to room temperature naturally, taking-up is weighed and record data, repeats above step until NACF carrier constant weight;
(2) (1) step gained NACF carrier being immersed molar concentration is the cobalt chloride (CoCl of 0.5mol/L 2) in the aqueous solution, 20 ℃ of following ultrasonic immersing 0.5h;
(3) will rinse well with deionized water through the NACF carrier of (2) step dipping, put into thermostatic drying chamber dry 24h under 110 ℃ afterwards;
(4) will put into the Muffle furnace roasting through the dry good NACF carrier of (3) step, at 400 ℃ of following roasting 6h, take out then and be positioned in the vacuum desiccator, under 0.1MPa vacuum, be cooled to room temperature naturally, get final product low-concentration hydrogen phosphide purification of the present invention with transition metal Co ion modification activated carbon fiber adsorbing substance.
When the Co ion modification activated carbon fiber adsorbing substance absorption with invention contained the waste gas of hydrogen phosphide, the adsorption process condition was: adsorbent 1.5g; Absorber inlet gas composition (volume ratio) PH 30.999%, nitrogen is carrier gas; The adsorption isotherm data utilize volumetric method to obtain, and test result is as shown in table 1.
Table 1
Adsorbing agent carrier The maceration extract kind Impregnation concentration/(mol/L) Adsorption capacity/(mg/g adsorbent)
Embodiment 1 Active carbon CoCl 2 0.2 4.856
Embodiment 2 Molecular sieve CoCl 2 0.2 4.868
Embodiment 3 NACF CoCl 2 0.2 19.674
Embodiment 4 NACF CoCl 2 0.1 16.470
Table 1 result shows, under the same concentration of same maceration extract, the adsorbent of the embodiment of the invention 3 has adsorption capacity more than 3 times than the known adsorbent that contains identical active component.The adsorbent that the influence of impregnation concentration makes the embodiment of the invention 3 has higher adsorption capacity than the adsorbent of the usefulness same vehicle of the embodiment of the invention 4 usefulness.

Claims (3)

1, a kind of transitional metal ion Co modified adsorbent preparation method who is used for purifying low-concentration phosphine is characterized in that step is as follows:
(1) the sorbing material carrier is carried out supersound washing and dry the processing, up to being processed into the constant weight carrier;
(2) select a kind of solubility cobalt salt that above-mentioned pretreated adsorbing agent carrier is carried out the ultrasonic immersing modification;
(3) to impregnated adsorbing agent carrier flushing, the dry processing;
(4) dried adsorbing agent carrier is carried out roasting, reduce to room temperature again.
2, modified adsorbent according to claim 1 is characterized in that:
(1) the sorbing material carrier is carried out supersound washing after, freeze-day with constant temperature 12~30h under 85~150 ℃ of temperature conditions is cooled to room temperature naturally under 0.1MPa vacuum;
(2) with the solubility cobalt salt to the modification of sorbing material carrier impregnation in, ultrasonic immersing 0.5~2h, the molar concentration that contains cobalt ions in the active component aqueous solution is 0.01~1mol/L;
(3) impregnated adsorbing agent carrier is adopted deionized water rinsing, then dry 12~30h under 85~150 ℃ of temperature;
(4) dried adsorbing agent carrier is at 200~600 ℃ of roasting temperature 2~8h, is cooled to room temperature then under 0.1MPa vacuum naturally.
3, modified adsorbent according to claim 2 is characterized in that: the sorbing material carrier adopts any in active carbon, molecular sieve and the NACF; Described solubility cobalt salt can the selective chlorination cobalt, in cobalt nitrate, cobaltous sulfate and the cobalt acetate any.
CNA2009100945024A 2009-05-22 2009-05-22 Method for preparing transitional metal ion Co modified adsorbent for purifying low-concentration phosphine Pending CN101564684A (en)

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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102806066A (en) * 2011-06-03 2012-12-05 中国石油化工股份有限公司 Purificant for adsorbing arsine and phosphorane in olefin tail gas and preparation method for purificant
CN102806065A (en) * 2011-06-03 2012-12-05 中国石油化工股份有限公司 Purifier for adsorbing arsenic hydride and hydrogen phosphide in olefin tail gas and preparation method thereof
CN104801272A (en) * 2015-04-15 2015-07-29 南通职业大学 Preparation method of cobalt-supported activated carbon as well as condition and device for adsorbing methylbenzene with cobalt-supported activated carbon

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102806066A (en) * 2011-06-03 2012-12-05 中国石油化工股份有限公司 Purificant for adsorbing arsine and phosphorane in olefin tail gas and preparation method for purificant
CN102806065A (en) * 2011-06-03 2012-12-05 中国石油化工股份有限公司 Purifier for adsorbing arsenic hydride and hydrogen phosphide in olefin tail gas and preparation method thereof
CN102806066B (en) * 2011-06-03 2014-08-06 中国石油化工股份有限公司 Purificant for adsorbing arsine and phosphorane in olefin tail gas and preparation method for purificant
CN102806065B (en) * 2011-06-03 2014-08-06 中国石油化工股份有限公司 Purifier for adsorbing arsenic hydride and hydrogen phosphide in olefin tail gas and preparation method thereof
CN104801272A (en) * 2015-04-15 2015-07-29 南通职业大学 Preparation method of cobalt-supported activated carbon as well as condition and device for adsorbing methylbenzene with cobalt-supported activated carbon

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Open date: 20091028