CN104609452A - Method for preparing activated calcium carbonate whisker from calcium carbide slag - Google Patents
Method for preparing activated calcium carbonate whisker from calcium carbide slag Download PDFInfo
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- CN104609452A CN104609452A CN201310563657.4A CN201310563657A CN104609452A CN 104609452 A CN104609452 A CN 104609452A CN 201310563657 A CN201310563657 A CN 201310563657A CN 104609452 A CN104609452 A CN 104609452A
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- calcium
- carbide slag
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Abstract
Disclosed is a method for preparing activated calcium carbonate whisker from calcium carbide slag. The method comprises the following steps: taking calcium carbide slag, ammonium chloride and carbon dioxide as raw materials; preparing ammonium chloride and ammoniacal liquor with a concentration about 20% through a boiling reaction from the calcium carbide slag and the ammonium chloride with a mol ratio in a range of 1.6-1.9; preparing ammonium carbonate from the ammoniacal liquor and carbon dioxide at a pH value ranging from 9 to 9.5; adjusting a concentration of a calcium chloride solution and an ammonium carbonate solution in a range of 0.1-1.5 mol/L; adding the calcium chloride solution and the ammonium carbonate solution dropwise at the same speed into a polyacrylamide solution with a concentration in a range of 0-0.4% under ultrasonic agitation; carrying out a reaction while stirring at a temperature range of 20-70 DEG C for 20-60 min to obtain calcium carbonate whisker; filtering and modifying the calcium carbonate whisker with sodium stearate in a concentration range of 0.01-0.05mol/L at room temperature for 0.1-1.0 h; filtering the obtained solution; and drying the obtained product at 105 DEG C to obtain the activated calcium carbonate whisker. The resultant ammonium chloride solution can be concentrated to a solution in a concentration range of 20-32% through evaporation for recycling.
Description
Denomination of invention
A kind of carbide slag prepares the method for active carbonic acid calcium pyroborate
1 technical field
The invention belongs to inorganic functional material field, relate to a kind of preparation method of active carbonic acid calcium pyroborate, under ultrasonic wave added, adopt double decomposition, preparation has the active carbonic acid calcium pyroborate that particle diameter is little, length-to-diameter ratio large, dispersiveness is high.
2 background technologies
Carbide slag is that calcium carbide route produces C
2h
2time produce trade waste, its main component is Ca (OH)
2, in strong basicity, sulfur-bearing phosphorus impurities, frowziness, particle is trickle, the strong water-retentivity of tool, and long-term arbitrarily stacking can cause serious environmental pollution.From last century domestic start to utilize calcium carbide route to produce PVC since, the safe handling of carbide slag is insoluble problem always.In recent years, by research and development, large-scale carbide slag obtains effective utilization substantially.At present, carbide slag comprehensive utilization approach is a lot, as produced building materials, Chemicals, the aspects such as the environmental protection treatment of waste gas, waste water.
Recently utilizing carbide slag production calcium carbonate to receive to pay close attention to widely, is also one of effective way of resource circulation utilization.Calcium carbonate crystal whisker refers to that length-to-diameter ratio is the staple fibre of 20-30, minor axis 0.5-1.0um.Compared with other fiber products, have the advantages that cost is low, whiteness is high, loading level is large.In addition, also there is the advantages such as preparation technology is simple, of many uses, environmentally safe.Chang Zuowei filler is used for the products such as plastics, rubber, papermaking.Greatly can reduce costs, improve the many advantages such as the shock resistance of material, flexural strength and dimensional stability.But there are two obvious problems in calcium carbonate and organic polymer compound tense: one is that calcium carbonate self easily produces serious agglomeration; Two be and avidity between organic polymer poor, affect composite property and improve.Therefore, be necessary to carry out surface modification to calcium carbonate, reduce its agglomeration and the avidity between raising and macromolecular material, to give full play to its enhancing modified effect.
At present, the synthetic method of calcium carbonate crystal whisker mainly contains 4 kinds: carborization, double decomposition, ureal antigen, Ca (HCO
3)
2thermal degradation method.Double decomposition is the Ca with solubility
2+and CO
3 2-for raw material, control reaction conditions, generate the method for calcium carbonate crystal whisker.Compared with additive method, have that product purity is high, form is easy to control, reaction efficiency advantages of higher.
Certain density calcium chloride is slowly added drop-wise in sodium carbonate solution and carries out replacement(metathesis)reaction by nineteen fifty-seven John L.Wary etc., successfully prepares aragonite calcium carbonate whisker.Zhang Li etc., by changing thermodynamic condition, adopt CaCl
2and Na
2cO
3dilute solution co-precipitation legal system obtain Aragonite Style Calcium Carbonate Whiskers.Experiment shows, the output of whisker and pattern are subject to the impact of temperature comparatively large, also affect by the rate of addition, stirring velocity, dropper diameter, foreign ion etc. of reactant concn, reactant simultaneously, thus propose the optimum process condition preparing whisker.
Liu Fei etc. take carbide slag as raw material, utilize HCl to carry out pre-treatment to carbide slag, control its pH=8.0, rear employing Na
2cO
3double decomposition have studied the impact on calcium carbonate crystal whisker such as reactant concn, rate of addition, temperature of reaction, stirring velocity, and final obtained length-to-diameter ratio reaches 30-60, and whisker structure is complete, the calcium carbonate crystal whisker of smooth surface, size uniform.
Tang Qin etc. adopt CaCl
2and Na
2cO
3double decomposition, in alcohol-water mixing solutions, by controlling the reaction conditions such as temperature of reaction, material concentration, under the condition not adding any additive, prepares that length is 10-30 μm, length-to-diameter ratio is the calcium carbonate crystal whisker of 20-30.
Cao Youming, by controlling temperature of reaction, prepares that particle diameter is 1 μm, length-to-diameter ratio is the calcium carbonate crystal whisker of 15.Zhang Xiuying for organic substrate, according to biomineralization principle, adopts double decomposition to synthesize the calcium carbonate crystal whisker of special appearance with beta-cyclodextrin (β-CD).Tongji University adopts double decomposition, disclose a kind of method controlling shape and appearance of calcium carbonate, its way is preparation sodium carbonate solution and calcium chloride solution, be placed in a kind of both sides of surface treated porous-film respectively, aragonite crystal form control agent is added in sodium carbonate solution side, reaction certain hour, centrifugally can obtain preparation of aragonite whisker.
Apply for a patent CN200610031408.0 and announce a kind of method being prepared high purity light calcium carbonate fine powder by carbide slag, by industrial waste carbide slag directly and ammonium chloride solution react, be converted into the mixing solutions of calcium chloride and ammoniacal liquor, in calcium chloride solution, pass into carbon dioxide after filtration carry out carbonation reaction, filter, washing, dries to obtain calcite type spherical light calcium carbonate micro mist, and ammonium chloride filtrate cycle uses.
Apply for a patent the preparation method that CN02160099.6 announces a kind of nm-class active calcium carbonate.Take carbide slag as raw material, by the calcium oxide obtained through purifying, filtering, calcine, the digestion that adds water is made into finite concentration calcium hydroxide slurry, itself and carbonic acid gas is made to carry out carburizing reagent, a certain amount of additive can be added as dilute sulphuric acid in carbonation reaction, sodium polyphosphate or zinc sulfate, finally obtain nano-calcium carbonate powder; Meanwhile, Al is added in the slurries be mixed with at aforementioned nano-calcium carbonate powder
2(SO
4)
3solution, rises to 70 DEG C and drips NaAc solution, is incubated to be warming up to 90 DEG C after 1 hour and to be incubated 1.5 hours again, and alumina-coated amount is 3 ~ 5% of theoretical calcium carbonate solid; Then, again organic-treating is carried out to nano-calcium carbonate powder, its method adopts stearic acid and Sodium dodecylbenzene sulfonate to carry out organic-treating to calcium carbonate, the consumption of stearic acid is 2 ~ 4%, the consumption of Sodium dodecylbenzene sulfonate is 1.5 ~ 2%, organic surface treatment temperature is 70 ~ 80 DEG C, and the treatment time is 1 ~ 2 hour; Filter, pulverize, final obtained nm-class active calcium carbonate powder.
Apply for a patent CN200810068715.51 and announce a kind of method that carbide slag prepares the fine and calcium carbonate superfine powder of different crystal forms, it is characterized in that the method is realized by following 4 processing steps: the pre-treatment of the first step carbide slag: mixed with clear water by carbide slag, obtained carbide slag slurries; The preparation of second step calcium chloride solution: by the carbide slag slurries that previous step is obtained, constantly drip HCl under the effect of stirring, until the pH value of water solution of carbide slag reaches about 8, filter, the filtrate obtained is calcium chloride solution; 3rd step replacement(metathesis)reaction prepares fine and calcium carbonate superfine powder: in calcium chloride solution, add activator, again solution is placed in thermostatic bath, then in solution, drip sodium carbonate solution, the temperature simultaneously controlling thermostatic bath arrives preset value, produces the precipitation of calcium carbonate of white; 4th step filtration drying: will obtain precipitation of calcium carbonate by previous step, filters, and dries, grinding, can obtain the fine and calcium carbonate superfine powder of different crystal forms respectively.
The present invention reacts with excessive carbide slag and ammonium chloride and prepares calcium chloride and ammonia, and ammonia and carbonic acid gas generate volatile salt.Under ultrasonication, with polypropylene amine solution for reaction medium, carry out the replacement(metathesis)reaction of calcium chloride and volatile salt, obtained calcium carbonate crystal whisker and ammonium chloride solution.In sodium stearate solution, activation modification is carried out to calcium carbonate crystal whisker, obtain active carbonic acid calcium pyroborate.The ammonium chloride that reaction generates, through evaporation concentration, is cycled to used in and reacts with carbide slag.Present method adopts ultrasonic wave added, and technique is simple, and product purity is high, particle diameter is little, length-to-diameter ratio is large, activity is high, and the ammonium chloride of generation can obtain recycle, has environmental protection, efficient, economic feature.
3 summary of the invention
The concrete preparation process of the present invention is as follows, carbide slag is added water and is made into the slurry that concentration is 20-50%, ball milling, crosses the sieve of more than 100 orders, gets the carbide slag under sieve, add chloride solid, keep the mol ratio of calcium hydroxide and ammonium chloride between 1.6-1.9, be heated to boiling, stirring reaction, the ammonia produced is entered in series connection absorption tower by gas distributor and absorbs, and obtaining concentration is about 20% ammoniacal liquor.By the ammoniacal liquor of this concentration by spray and carbon dioxide content 10-20% air gas mixture backward reaction in packing tower, keeping temperature of reaction at 20-40 DEG C, is obtained sal volatile between 9.0-9.5 to pH.The solvent portions that carbide slag and ammonium chloride react, keeps pH to be greater than 10, cooling, filters, washing, collect filtrate, obtain the calcium chloride solution that concentration is greater than more than 20%.
Volatile salt and calcium chloride solution are diluted for 0.1-1.5mol/L, add ultrasonic reaction in the polyacrylamide solution of the 0-4% of 1-3 times of volatile salt and calcium chloride solution volume with identical speed under stirring, control temperature of reaction is 20-70 DEG C, the reactant joining day is at 20-60min, centrifuging, the crystal whisker-shaped calcium carbonate of generation being added immediately concentration is modification 0.1-1.0h in the sodium stearate of 0.01-0.05mol/L, filters, 105 DEG C of oven dry, obtain active carbonic acid calcium pyroborate.After the filtrate cycle of containing ammonium chloride uses 1-4 time, when wherein ammonium chloride concentration reaches more than 1mol/L, utilize the ammonium chloride solution of multiple-effect evaporation simmer down to concentration 20-32%, cycle applications prepares calcium chloride and ammonia in reacting with carbide slag, reaches the recycle object of ammonium chloride.
Compared with prior art, having significant advantage is in the present invention:
1. the present invention is raw material with carbide slag, and carbide slag is excessive, and the pH controlling whole reaction system, more than 10, ensure that the purity of product.
2. calcium carbonate length-to-diameter ratio is controlled with polyacrylamide, sodium stearate is properties-correcting agent, under ultrasonic wave added, prepare active carbonic acid calcium pyroborate, the method can not only prepare the active carbonic acid calcium pyroborate that particle diameter is little, length-to-diameter ratio is large, can also solve the problem of reuniting in nano-calcium carbonate preparation process.
3. ammonium chloride can carry out recycle, decreases and pollutes and reduce productive expense.
4 embodiments
In enforcement engineering, following scheme can be paid the utmost attention to.
Embodiment 1
Carbide slag adds water and is made into the slurry that concentration is 20%, ball milling, cross the sieve of more than 100 orders, get the carbide slag under sieve, add chloride solid, keep the mol ratio of calcium hydroxide and ammonium chloride 1.8, be heated to boiling, stirring reaction, the ammonia of generation is entered in series connection absorption tower by gas distributor and absorbs, and obtaining concentration is about 20% ammoniacal liquor.Be 15% air gas mixture in packing tower backward reaction by spray with carbon dioxide content by the ammoniacal liquor of this concentration, keeping temperature of reaction lower than 35 DEG C, is obtained sal volatile between 9.0-9.5 to pH.The solvent portions that carbide slag and ammonium chloride react, keeps pH to be greater than 10, cooling, filters, washing, collect filtrate, obtain the calcium chloride solution that concentration is greater than 20%.
Volatile salt and calcium chloride solution are diluted for 0.15mol/L, add in the polyacrylamide solution of 0.25% of 1 times of volatile salt and calcium chloride solution volume with identical speed, ultrasonic power 250W, stirring velocity 200r/min, temperature of reaction 60 DEG C, reactant joining day 30min, centrifuging, the crystal whisker-shaped calcium carbonate of generation being added immediately concentration is modification 0.5h in the sodium stearate solution of 0.02mol/L, filters, 105 DEG C of oven dry, obtain active carbonic acid calcium pyroborate.After the filtrate cycle of containing ammonium chloride uses 4 times, utilize the ammonium chloride solution of multiple-effect evaporation simmer down to concentration 20%, cycle applications prepares calcium chloride and ammonia in reacting with carbide slag.
Embodiment 2
Carbide slag adds water and is made into the slurry that concentration is 30%, ball milling, cross the sieve of more than 100 orders, get the carbide slag under sieve, add chloride solid, keep the mol ratio of calcium hydroxide and ammonium chloride 1.6, be heated to boiling, stirring reaction, the ammonia of generation is entered in series connection absorption tower by gas distributor and absorbs, and obtaining concentration is about 20% ammoniacal liquor.Be 15% air gas mixture in packing tower backward reaction by spray with carbon dioxide content by the ammoniacal liquor of this concentration, keeping temperature of reaction lower than 35 DEG C, is obtained sal volatile between 9.0-9.5 to pH.The solvent portions that carbide slag and ammonium chloride react, keeps pH to be greater than 10, cooling, filters, washing, collect filtrate, obtain the calcium chloride solution that concentration is greater than 25%.
Volatile salt and calcium chloride solution are diluted for 1mol/L, add in the polyacrylamide solution of 0.5% of 3 times of volatile salts and calcium chloride solution volume with identical speed, ultrasonic power 250W, stirring velocity 200r/min, temperature of reaction is 50 DEG C, reactant joining day 45min, centrifuging, the crystal whisker-shaped calcium carbonate of generation being added immediately concentration is modification 0.5h in the sodium stearate solution of 0.04mol/L, filters, 105 DEG C of oven dry, obtain active carbonic acid calcium pyroborate.The filtrate of containing ammonium chloride utilizes the ammonium chloride solution of multiple-effect evaporation simmer down to concentration 20%, and cycle applications prepares calcium chloride and ammonia in reacting with carbide slag.
Embodiment 3
Carbide slag adds water and is made into the slurry that concentration is 20%, ball milling, cross the sieve of more than 100 orders, get the carbide slag under sieve, add chloride solid, keep the mol ratio of calcium hydroxide and ammonium chloride 1.8, be heated to boiling, stirring reaction, the ammonia of generation is entered in series connection absorption tower by gas distributor and absorbs, and obtaining concentration is about 20% ammoniacal liquor.Be 20% air gas mixture in packing tower backward reaction by spray with carbon dioxide content by the ammoniacal liquor of this concentration, keeping temperature of reaction lower than 35 DEG C, is obtained sal volatile between 9.0-9.5 to pH.The solvent portions that carbide slag and ammonium chloride react, keeps pH to be greater than 10, cooling, filters, washing, collect filtrate, obtain the calcium chloride solution that concentration is greater than 20%.
Volatile salt and calcium chloride solution are diluted for 1.5mol/L, add in the polyacrylamide solution of 1.25% of 3 times of volatile salts and calcium chloride solution volume with identical speed, ultrasonic power 250W, stirring velocity 200r/min, temperature of reaction is 30 DEG C, reactant joining day 60min, centrifuging, the crystal whisker-shaped calcium carbonate of generation being added immediately concentration is modification 1h in the sodium stearate solution of 0.05mol/L, filters, 105 DEG C of oven dry, obtain active carbonic acid calcium pyroborate.The filtrate of containing ammonium chloride utilizes the ammonium chloride solution of multiple-effect evaporation simmer down to concentration about 30%, and cycle applications prepares calcium chloride and ammonia in reacting with carbide slag.
Claims (6)
1. a carbide slag prepares the method for active carbonic acid calcium pyroborate, mainly comprise carbide slag and ammonium chloride reaction prepare calcium chloride and sal volatile, in polyacrylamide solution, under ultrasonic, agitation condition, prepare calcium carbonate crystal whisker by replacement(metathesis)reaction, obtain active carbonic acid calcium pyroborate with sodium stearate modification.The ammonium chloride generated and carbide slag circulating reaction.
2., as the carbide slag in right 1 and ammonium chloride reaction, ensure that carbide slag is excessive, the mol ratio of calcium hydroxide and ammonium chloride is between 1.6-1.9.
3. as the calcium chloride in right 1 and sal volatile concentration control between 0.1-1.5mol/L.
4. the concentration of polyacrylamide solution as calcium chloride in right 1 and volatile salt reaction is 0-4%.
5. if the sodium stearate concentration of modified calcium carbonate whisker in right 1 is 0.01-0.05mol/L.
6. the preparation condition as the calcium carbonate crystal whisker in right 1 is ultrasonic agitation reaction.
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Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105288637A (en) * | 2015-11-23 | 2016-02-03 | 上海应用技术学院 | Calcium carbonate microsphere preparation method |
| CN105329928A (en) * | 2015-12-10 | 2016-02-17 | 湖南化工职业技术学院 | Activation method for nanometer calcium carbonate |
| CN107935014A (en) * | 2017-12-08 | 2018-04-20 | 沈阳化工大学 | A kind of ammonium salt dissolving and circulation ammonia process extract the production method of calcium carbonate from calcite |
| CN110745853A (en) * | 2018-07-24 | 2020-02-04 | 唐山市丰南区奉岗灰业有限公司 | Calcium oxide and preparation method thereof |
| CN112429758A (en) * | 2020-12-08 | 2021-03-02 | 原初科技（北京）有限公司 | Fixation of CO by carbide slag2And a process for preparing calcium carbonate |
| CN113233490A (en) * | 2021-06-02 | 2021-08-10 | 桐乡市思远环保科技有限公司 | Method for preparing nano calcium carbonate by using natural calcium carbonate |
| CN114772625A (en) * | 2022-04-12 | 2022-07-22 | 四川大学 | Method for dissolving out calcium ions in carbide slag and method for mineralizing and storing CO by using calcium ions in carbide slag2Application of co-produced light calcium carbonate |
| CN116239903A (en) * | 2023-03-06 | 2023-06-09 | 湖北工业大学 | Preparation method of carbide slag-based carbonized inorganic refrigeration coating |
-
2013
- 2013-11-05 CN CN201310563657.4A patent/CN104609452A/en active Pending
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105288637A (en) * | 2015-11-23 | 2016-02-03 | 上海应用技术学院 | Calcium carbonate microsphere preparation method |
| CN105288637B (en) * | 2015-11-23 | 2018-05-08 | 上海应用技术学院 | A kind of preparation method of calcium carbonate microspheres |
| CN105329928A (en) * | 2015-12-10 | 2016-02-17 | 湖南化工职业技术学院 | Activation method for nanometer calcium carbonate |
| CN107935014A (en) * | 2017-12-08 | 2018-04-20 | 沈阳化工大学 | A kind of ammonium salt dissolving and circulation ammonia process extract the production method of calcium carbonate from calcite |
| CN110745853A (en) * | 2018-07-24 | 2020-02-04 | 唐山市丰南区奉岗灰业有限公司 | Calcium oxide and preparation method thereof |
| CN112429758A (en) * | 2020-12-08 | 2021-03-02 | 原初科技（北京）有限公司 | Fixation of CO by carbide slag2And a process for preparing calcium carbonate |
| CN113233490A (en) * | 2021-06-02 | 2021-08-10 | 桐乡市思远环保科技有限公司 | Method for preparing nano calcium carbonate by using natural calcium carbonate |
| CN114772625A (en) * | 2022-04-12 | 2022-07-22 | 四川大学 | Method for dissolving out calcium ions in carbide slag and method for mineralizing and storing CO by using calcium ions in carbide slag2Application of co-produced light calcium carbonate |
| CN116239903A (en) * | 2023-03-06 | 2023-06-09 | 湖北工业大学 | Preparation method of carbide slag-based carbonized inorganic refrigeration coating |
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