Background technology
Because high-strength, the high-ductility that still has under quantum size, quantum tunneling effect and its special light, electrical characteristic, high magnetic resistance phenomenon, nonlinear resistance phenomenon and the high temperature of nano silicon, the unusual characteristic of good stability make nano silicon have a wide range of applications in high-tech areas such as communication, electronics, aviations.Preparation method of nano silicon dioxide mainly adopts following four kinds of methods at present, the one, vapor phase process: with the silicon tetrachloride is raw material, adopt the hydrolysis under hydrogen-oxygen air-flow high temperature of silicon tetrachloride gas to make the silicon-dioxide of smoke-like, this method complex process, production cost height are unfavorable for suitability for industrialized production; The 2nd, the precipitator method: silicate obtains to loosen, be precipitated out with flocculent structure by acidifying, and the hard aggregation phenomenon takes place this method control process complexity easily, is difficult to obtain the high-quality silicon-dioxide of stable in properties; The 3rd, micro emulsion method: with the metal-salt wiring solution-forming, add certain precipitation agent and form microemulsion, than zonule inner control micelle nucleation and growth, again with micelle and separated from solvent and thermal treatment, promptly obtain corresponding ultra-fine grain, this method complex process, cost is higher; The 4th, sol-gel method: this method is to be initial feed with metal alkoxide or inorganic salt, utilize the hydrolysis of alkoxide and inorganic salt or the colloidal sol that precipitin reaction prepares oxide compound, and then carry out the conversion process of collosol and gel, gel carries out ageing, drying and thermal treatment again and obtains product, and this method raw materials cost is higher.All there is defective separately in these four kinds of methods, difficult preparation ideal, the high-purity nano silicon-dioxide cheaply realized.
Resinous shale is as a kind of potential energy, and its reserves are bigger.The main approach that utilizes of resinous shale is exactly that shale oil and direct combustion power generation are produced in low-temperature pyrolysis at present, but can produce a large amount of lime-ash after utilizing.Along with continually developing of resinous shale, national oil shale mine is faced with the resinous shale lime-ash and handles this huge difficult problem, and the resinous shale lime-ash of accumulation has caused the serious environmental pollution on the one hand, has also caused the serious waste of resource on the other hand.Therefore how improving the comprehensive utilization ratio of resinous shale lime-ash, improve the added value of oil shale resources, is the technical problem that needs to be resolved hurrily.The cindery main chemical compositions of Fushun oil shale is SiO
2And Al
2O
3, SiO wherein
2Content 57.80%, Al
2O
3Content be 17.84%, Fe
2O
3Content be 8.62%, organic and crystal water content is 10.14%, remaining is oxide compounds such as Ti, Mn, Ca, Mg, K, P, Na.Because SiO in the resinous shale lime-ash
2Content higher, therefore utilize the resinous shale lime-ash to prepare nano silicon and have huge economic and environment protection significance.Chinese patent CN101037204 discloses a kind of method of utilizing oil shale ash to prepare white carbon black, may further comprise the steps: 1) with the oil shale ash fragmentation, 2) kerosene shale ash after the fragmentation is mixed with NaOH solution, reacted in agitator under 20~200 ℃ 0.5~24 hour, stirring velocity is: 100~800r/min; 3) with above-mentioned reaction mass by vacuum filtration, make reaction solution be divided into caustic solubility and insoluble two parts of alkali; 4) in above-mentioned filtrate, add dispersion agent, and, disperseed 0.5~4 hour with magnetic stirrer simultaneously with sulfuric acid or salt acid for adjusting pH value to 3.0~10.0; 5) still aging 0.5~24 hour, produce white flocks; 6) above-mentioned throw out is filtered; 7) filter cake is carried out vacuum-drying, drying temperature is 40~80 ℃, and the product that obtains has shortcomings such as particle diameter is big, foreign matter content height.
Summary of the invention
Purpose of the present invention is exactly at above-mentioned the deficiencies in the prior art, and a kind of method for preparing high pure nano silicon dioxide with the shale lime-ash is provided.
The objective of the invention is to realize in the following manner:
With the method for preparing high pure nano silicon dioxide from oil shale slag, comprise following order and step:
A, pulverizing, calcining: the kerosene shale ash ground-slag is broken into less than<140 purpose fine powders, calcines 2~3 hours to remove oil refining remaining organic matter in back and further activated clay mineral at 550~750 ℃;
B, sour molten: the resinous shale lime-ash after the calcining adds the acid dissolving and makes porous silica, and the resinous shale lime-ash after the calcining and the mass ratio of sulphuric acid soln are 1: 2~5; The massfraction of sulphuric acid soln is 20~30%; Temperature of reaction is 70~100 ℃; Reaction times is 2~5 hours;
C, alkali are molten: water glass is made in porous silica and caustic soda reaction, and porous silica is 1: 2~5 with the mass ratio that caustic soda reacts; The massfraction of white liquor is 20~40%; Temperature of reaction is 70~100 ℃; Reaction times is 2~5 hours;
D, the preparation gel: with the water glass thin up to 500ml, place the ultra-sonic oscillation agitator, 1~3% the tensio-active agent that adds the solution total mass again, adding concentration is the acid of 0.5~1.0mol/L, stir while adding, endpoint pH is 4~8, and the preparation gelation temperature is controlled at 30~70 ℃;
E, ageing: ageing temperature 40~60, digestion time are 8~12 hours;
F, with the gel after the ageing after filtration, the washing, with the propyl carbinol azeotropic distillation drying, 500~750 ℃ of calcinings obtain product;
Purpose of the present invention can also realize in the following manner:
The kind that steps d prepares in the gelation process acid is any in sulfuric acid, hydrochloric acid or the acetic acid; The kind of tensio-active agent is any one or two kinds of in polyoxyethylene glycol (6000), polyoxyethylene glycol (10000), polyoxyethylene glycol (20000), oleyl amine or the oleic acid.
Positively effect: produce though Tai-Ace S 150 is arranged in the technological process of the present invention and be dissolved in other sour impurity mixed solutions, white residue and metabisulfite solution, but Tai-Ace S 150 and other impurity mixed solutions that are dissolved in acid can be used for preparing aluminum oxide, white residue can be used as material of construction, metabisulfite solution evaporated to obtain the sodium sulfate solid, so the present invention is environmental protection.
Raw material sources of the present invention are extensive, turn waste into wealth, and both solved the resinous shale lime-ash and handled rare problem, also reduced environmental pollution.The good performance indexes of the nano silicon of the present invention's preparation, the particle diameter of nano silicon is 5~10nm, specific surface area is up to 697m
2/ g, SiO
2〉=99.9476%; Al
2O
3≤ 0.0068%; Fe
2O
3≤ 0.0059%; CaO≤0.0035%; MgO≤0.0050%; Other impurity≤0.0312%, and technology is simple, and with low cost.
Embodiment
The present invention is described in further detail below in conjunction with embodiment:
With the method for preparing high pure nano silicon dioxide from oil shale slag, comprise following order and step:
A, pulverizing, calcining: the kerosene shale ash ground-slag is broken into less than<140 purpose fine powders, calcines 2~3 hours to remove oil refining remaining organic matter in back and further activated clay mineral at 550~750 ℃;
B, sour molten: the resinous shale lime-ash after the calcining adds the acid dissolving and makes porous silica, and the resinous shale lime-ash after the calcining and the mass ratio of sulphuric acid soln are 1: 2~5; The massfraction of sulphuric acid soln is 20~30%; Temperature of reaction is 70~100 ℃; Reaction times is 2~5 hours;
C, alkali are molten: water glass is made in porous silica and caustic soda reaction, and porous silica is 1: 2~5 with the mass ratio that caustic soda reacts; The massfraction of white liquor is 20~40%; Temperature of reaction is 70~100 ℃; Reaction times is 2~5 hours;
D, the preparation gel: with the water glass thin up to 500ml, place the ultra-sonic oscillation agitator, 1~3% the tensio-active agent that adds the solution total mass again, adding concentration is the acid of 0.5~1.0mol/L, stir while adding, endpoint pH is 4~8, and the preparation gelation temperature is controlled at 30~70 ℃;
E, ageing: ageing temperature 40~60, digestion time are 8~12 hours;
F, with the gel after the ageing after filtration, the washing, with the propyl carbinol azeotropic distillation drying, 500~750 ℃ of calcinings obtain product;
The kind that steps d prepares in the gelation process acid is any in sulfuric acid, hydrochloric acid or the acetic acid; The kind of tensio-active agent is any one or two kinds of in polyoxyethylene glycol (6000), polyoxyethylene glycol (10000), polyoxyethylene glycol (20000), oleyl amine or the oleic acid.
Embodiment 1:
Get the resinous shale lime-ash after 100g pulverizes, calcined two hours for 550 ℃, put into after the cooling and can burn vessel, to burning sulphuric acid soln (98% the vitriol oil 50ml that adds 300g30% in the vessel, water 210ml), heating while stirring, be warming up to 95 ℃, constant temperature 5 hours stops to stir, treat to begin after temperature is reduced to 70 ℃ to filter, remove filtrate, get porous silica, add 20% sodium hydroxide solution 300g (sodium hydroxide 60g, water 240g), stirring is warming up to 100 ℃, constant temperature 5 hours stops to stir, and treats to begin after temperature is reduced to 70 ℃ washing, filter, be washed till neutrality, remove residue, get water glass, the thin up water glass solution is to 500ml.With the dilution after water glass solution weigh 650g, press 1% adding polyoxyethylene glycol (10000) 6.5g of the quality of solution, polyoxyethylene glycol (10000) is put into ultrasonic cleaner with beaker after all dissolving, and the ultrasonic water bath temperature is 50 ℃, after water glass solution is warming up to 50 ℃, when the sulphuric acid soln (get 98% vitriol oil 220ml add water be made into 4L solution) that in beaker, adds 0.5mol/L slowly, the pH=4 of solution, stop to add acid, get gel, take out beaker.With preservative film the beaker mouth is sealed, put into 60 ℃ of baking oven ageing ageing temperature, ageing 8 hours is with the gel-filtration after the ageing, wash to neutrality, transfer in the distilling flask, in distilling flask, add the 200ml propyl carbinol, when distillation temperature reaches 105 ℃, pour mixture into beaker, put into baking oven, 120 ℃ of oven dry, the sample after the oven dry are put into 550 ℃ of calcinings in the retort furnace, promptly get nano silicon.
Embodiment 2:
Get the resinous shale lime-ash after 100g pulverizes, calcined two hours for 550 ℃, put into after the cooling and can burn vessel, to burning sulphuric acid soln (98% the vitriol oil 50ml that adds 300g30% in the vessel, water 210ml), heating while stirring, be warming up to 95 ℃, constant temperature 5 hours stops to stir, treat to begin after temperature is reduced to 70 ℃ to filter, remove filtrate, get porous silica, add 30% sodium hydroxide solution 300g (sodium hydroxide 90g, water 210g), stirring is warming up to 95 ℃, constant temperature 3 hours stops to stir, and treats to begin after temperature is reduced to 70 ℃ washing, filter, be washed till neutrality, remove residue, get water glass, thin up water glass is molten to 500ml.With the dilution after water glass solution weigh 625g, press 2% adding polyoxyethylene glycol (20000) 12.5g of the quality of solution, polyoxyethylene glycol is put into ultrasonic cleaner with beaker after all dissolving, and the ultrasonic water bath temperature is 50 ℃, after water glass solution is warming up to 50 ℃, when the acetum (get 99% Glacial acetic acid 240ml add water be made into 4L solution) that in beaker, adds 0.5mol/L slowly, the pH=5 of solution, stop to add acid, get gel, take out beaker.With preservative film the beaker mouth is sealed, put into the baking oven ageing, 60 ℃ of ageings of ageing temperature 8 hours, with the gel-filtration after the ageing, wash to neutrality, transfer in the distilling flask, in distilling flask, add the 200ml propyl carbinol, when distillation temperature reaches 105 ℃, pour mixture into beaker, put into baking oven, 120 ℃ of oven dry.Sample after the oven dry is put into 550 ℃ of calcinings in the retort furnace, promptly gets nano silicon.
Embodiment 3:
Get the resinous shale lime-ash after 100g pulverizes, calcined two hours for 550 ℃, put into after the cooling and can burn vessel, to burning sulphuric acid soln (98% the vitriol oil 67ml that adds 400g30% in the vessel, water 280ml), heating while stirring, be warming up to 95 ℃, constant temperature 5 hours stops to stir, treat to begin after temperature is reduced to 70 ℃ to filter, remove filtrate, get porous silica, add 40% sodium hydroxide solution 300g (sodium hydroxide 120g, water 180g), stirring is warming up to 100 ℃, constant temperature 5 hours stops to stir, and treats to begin after temperature is reduced to 70 ℃ washing, filter, be washed till neutrality, remove residue, get water glass, thin up water glass is molten to 500ml.With the dilution after water glass solution weigh 725g, press 2% adding polyoxyethylene glycol (10000) 14.5g of the quality of solution, polyoxyethylene glycol (10000) is put into ultrasonic cleaner with beaker after all dissolving, and the ultrasonic water bath temperature is 50 ℃, after water glass solution is warming up to 50 ℃, when the sulphuric acid soln (get 98% vitriol oil 220ml add water be made into 4L solution) that in beaker, adds 0.5mol/L slowly, the pH=4 of solution, stop to add acid, get gel, take out beaker.With preservative film the beaker mouth is sealed, put into the baking oven ageing, 60 ℃ of ageing temperature, ageing 8 hours with the gel-filtration after the ageing, wash to neutrality, is directly put into baking oven, 120 ℃ of oven dry.Sample after the oven dry is put into 550 ℃ of calcinings in the retort furnace, promptly gets nano silicon.
Embodiment 4:
Get the resinous shale lime-ash after 100g pulverizes, calcined two hours, and put into after the cooling and can burn vessel for 550 ℃, to burning sulphuric acid soln (98% the vitriol oil 108ml that adds 300g65% in the vessel, water 105ml), heating is warming up to 95 ℃, constant temperature 5 hours while stirring, stop to stir, treat to begin after temperature is reduced to 70 ℃ to filter, remove filtrate, get porous silica, sodium hydroxide solution 400g (the sodium hydroxide 80g of adding 20%, water 320g), stirring is warming up to 90 ℃, and constant temperature 5 hours stops to stir, treat to begin after temperature is reduced to 70 ℃ washing, filter, be washed till neutrality, remove residue, get water glass,, the thin up water glass solution is to 500ml.With the water glass solution after the dilution, weigh 675g, press solution quality 1% add polyoxyethylene glycol (20000) 6.75g, polyoxyethylene glycol (20000) is all after the dissolving, beaker is put into ultrasonic cleaner, the ultrasonic water bath temperature is 50 ℃, after water glass solution is warming up to 50 ℃, adds the sulphuric acid soln (get 98% vitriol oil 220ml add water be made into 4L solution) of 0.5mol/L slowly in beaker, during the pH=7 of solution, stop to add acid, get gel, take out beaker.With preservative film the beaker mouth is sealed, put into the baking oven ageing, 60 ℃ of ageings of ageing temperature 10 hours, with the gel-filtration after the ageing, wash to neutrality, transfer in the distilling flask, in distilling flask, add the 200ml propyl carbinol, when distillation temperature reaches 105 ℃, pour mixture into beaker, put into baking oven, 120 ℃ of oven dry.Sample after the oven dry is put into 550 ℃ of calcinings in the retort furnace, promptly gets nano silicon.