CN113416433A - Preparation method of amorphous chromium hydroxide dispersoid - Google Patents
Preparation method of amorphous chromium hydroxide dispersoid Download PDFInfo
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Abstract
The invention provides a preparation method of an amorphous chromium hydroxide dispersoid, which comprises the steps of firstly adopting an ultrasonic coupling hypergravity field to strengthen micro mixing in a chromium hydroxide nucleation process to prepare amorphous ultrafine chromium hydroxide nanoparticles, then carrying out surface modification through a surfactant, using the ultrasonic field coupling hypergravity field to redisperse the chromium hydroxide, and enabling the ultrafine particles to be uniformly redispersed through strong shearing of a hypergravity rotating packed bed and the vibration effect of the ultrasonic field on the nanoparticles so as to prepare the amorphous ultrafine chromium hydroxide dispersoid which can be stably dispersed in a solvent.
Description
Technical Field
The invention relates to the field of preparation of nano materials, in particular to a preparation method of an amorphous chromium hydroxide dispersoid.
Background
Chromium hydroxide, also known as chrome blue, is an important intermediate of inorganic pigments and chemical products, and is also a commonly used catalyst for catalyzing thermal decomposition of ammonium perchlorate. The nanometer chromium hydroxide can also be used as the middle layer of the nanometer filter membrane for intercepting molecules with large molecular weight and bivalent or high-valent salt ions. As an additive of pigment or paint product, the nano chromium hydroxide which has small particle size and narrow particle size distribution range and can be stably dispersed in liquid phase can improve the color stability of the product containing the chromium hydroxide pigment, improve the product quality and prolong the storage life. As a catalyst for thermal decomposition of ammonium perchlorate, the small-particle-size stably-dispersed chromium hydroxide can be uniformly dispersed in the ammonium perchlorate solid and expose more catalytic activity sites, so that the peak temperature of thermal decomposition of the ammonium perchlorate is effectively reduced and the heat release of decomposition is improved. It can be seen that the small particle size and stable dispersion effect are one of the performance indexes of chromium hydroxide, and at present, some reports have been made on the preparation method of nano chromium hydroxide at home and abroad, for example, the literature, "Huangzhonglin" and the basic and application research of chromium hydroxide [ D]2016, using sodium hydroxide and ammonia water as precipitant to react with chromium salt in a beaker for precipitation to obtain the nanocrystalline chromium hydroxide. The size of the chromium hydroxide nano-particles prepared by the method is larger than 47nm, the particle size distribution is wide, and the dispersion effect is unknown. Document "LIANG S, ZHANG H, XU H.preparation of hexagonal and amophorus chloroxides by simple hydrolysis of KxCrOy[J].Transaction of Nonferrous Metal Society of China,2020,30(5) 1397-3CrO4The precursor prepares amorphous chromium hydroxide, and the size of the product obtained by the method is more than 200nm, but the product is difficult to stably disperse in aqueous solution. In addition, the literature "LvShiping, Xuyangqing, VanShihui, et al, the influence of PEG and PVP on the stability of the chromium hydroxide colloid [ C]In 2008, it was mentioned that adding appropriate amounts of PEG and PVP is beneficial to improve the stability of the chromium hydroxide colloid. However, the Zeta potential value of the modified chromium hydroxide colloid obtained by the method is low, and the chromium hydroxide colloid can be stabilized for about 60min under the optimized condition. That is, the conventional method cannot prepare chromium hydroxide particles with small particle size and good dispersibility.
Disclosure of Invention
In order to solve at least one of the above problems, an aspect of the present invention provides a method for preparing an amorphous chromium hydroxide dispersion, comprising:
pumping the chromium salt solution and the precipitator solution into a hypergravity reactor for a set circulating time to obtain chromium hydroxide particles; feeding ultrasound when the hypergravity reactor operates;
surface modification is carried out on the chromium hydroxide particles by adopting a surfactant;
and pumping the modified chromium hydroxide particles and the solvent into the high-gravity reactor to obtain the amorphous chromium hydroxide dispersion.
In a preferred embodiment, the surfactant comprises: one or more of sodium citrate, sodium tartrate, cetyl trimethyl ammonium bromide, polyvinylpyrrolidone, cetyl trimethyl ammonium chloride and polyethylene glycol.
In a preferred embodiment, the precipitation agent comprises: sodium hydroxide, potassium hydroxide, ammonia, sodium borohydride, and hydrazine hydrate.
In a preferred embodiment, the surfactant is present in an amount of 5 wt% to 50 wt% of the amount of chromium salt.
In a preferred embodiment, the chromium salt solution comprises: one or more of chromium nitrate, chromium sulfate, chromium chloride and chromium perchlorate.
In a preferred embodiment, the solvent is water.
In a preferred embodiment, the hypergravity reactor is a rotating packed bed.
In a preferred embodiment, hydrophobic packing is provided within the rotating packed bed.
In a preferred embodiment, the hydrophobic filler is formed with a plurality of through-going channels.
In a preferred embodiment, the pore channel is in a micro-nano scale.
The invention has the beneficial effects that:
the invention provides a preparation method of amorphous chromium hydroxide dispersoid, which comprises the following steps of pumping a chromium salt solution and a precipitator solution into a super-gravity reactor for a set time period in a circulating manner to obtain chromium hydroxide particles; feeding ultrasound when the hypergravity reactor operates; then, surface modification is carried out on the chromium hydroxide particles by adopting a surfactant; finally, pumping the modified chromium hydroxide particles and a solvent into the hypergravity reactor to obtain an amorphous chromium hydroxide dispersoid; according to the invention, the micro-mixing in the nucleation process of the chromium hydroxide is enhanced by adopting an ultrasonic coupling supergravity field to prepare the amorphous ultra-small chromium hydroxide nano-particles, then the surface modification is carried out by using a surfactant, the chromium hydroxide is re-dispersed by using the ultrasonic field coupling supergravity field, and the ultra-small particle size nano-particles can be uniformly re-dispersed by virtue of the strong shearing of a supergravity rotating packed bed and the vibration effect of the ultrasonic field on the nano-particles, so that the amorphous ultra-small chromium hydroxide nano-dispersion capable of being stably dispersed in a solvent is prepared.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and other drawings can be obtained by those skilled in the art without creative efforts.
FIG. 1 is a Transmission Electron Microscope (TEM) image of the product of example 1 of the present invention.
FIG. 2 is a statistical plot of the particle size distribution of the product prepared in example 1 of the present invention.
FIG. 3 is an X-ray powder diffraction pattern of the product of example 1 of the present invention.
FIG. 4 shows the Zeta potential as a function of the standing time for the product of example 2 according to the invention.
FIG. 5 is an electron photograph of an aqueous dispersion of amorphous chromium hydroxide obtained in example 1 of the present invention.
FIG. 6 is a Transmission Electron Microscope (TEM) image of the product of example 2 of the present invention.
FIG. 7 is a statistical plot of the particle size distribution of the product prepared in example 2 of the present invention.
FIG. 8 is an X-ray powder diffraction pattern of the product of example 2 of the present invention.
FIG. 9 shows the Zeta potential as a function of the standing time for the product of example 2 according to the invention.
FIG. 10 is an electron photograph of an aqueous dispersion of amorphous chromium hydroxide obtained in example 2 of the present invention.
FIG. 11 is a Transmission Electron Microscope (TEM) image of a product of comparative example 1 of the present invention.
FIG. 12 is an X-ray powder diffraction pattern of the product of comparative example 1 of the present invention.
FIG. 13 is an electron photograph of an aqueous dispersion of amorphous chromium hydroxide obtained in comparative example 1 of the present invention.
FIG. 14 is a TG-DSC graph of the product of example 1 catalyzing the thermal decomposition of ammonium perchlorate.
FIG. 15 is a TG-DSC graph of the product of comparative example 1 catalyzing the thermal decomposition of ammonium perchlorate.
FIG. 16 is a schematic flow chart of a method for preparing a novel amorphous chromium hydroxide dispersion according to an embodiment of the present invention.
Detailed Description
The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is apparent that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be obtained by a person skilled in the art without any inventive step based on the embodiments of the present invention, are within the scope of the present invention.
The inventor of the invention finds that the conventional method can not prepare the chromium hydroxide particles with small particle size and good dispersion performance, and the industry still has no better solution, and the research progress in the related aspects is always stopped.
Through experimental investigation of the inventor, the present invention attempts to adopt a step method to carry out equipment of chromium hydroxide dispersion, and the present invention provides a novel preparation method of amorphous chromium hydroxide dispersion, as shown in fig. 16, which specifically comprises:
s1: pumping the chromium salt solution and the precipitator solution into a hypergravity reactor for a set circulating time to obtain chromium hydroxide particles; feeding ultrasound when the hypergravity reactor operates;
s2: surface modification is carried out on the chromium hydroxide particles by adopting a surfactant;
s3: pumping the modified chromium hydroxide particles and a solvent into the high-gravity reactor to obtain the amorphous chromium hydroxide dispersoid.
The invention provides a preparation method of amorphous chromium hydroxide dispersoid, which comprises the following steps of pumping a chromium salt solution and a precipitator solution into a super-gravity reactor for a set time period in a circulating manner to obtain chromium hydroxide particles; feeding ultrasound when the hypergravity reactor operates; then, surface modification is carried out on the chromium hydroxide particles by adopting a surfactant; finally, pumping the modified chromium hydroxide particles and a solvent into the hypergravity reactor to obtain an amorphous chromium hydroxide dispersoid; according to the invention, the micro-mixing in the nucleation process of the chromium hydroxide is enhanced by adopting an ultrasonic coupling supergravity field to prepare the amorphous ultra-small chromium hydroxide nano-particles, then the surface modification is carried out by using a surfactant, the chromium hydroxide is re-dispersed by using the ultrasonic field coupling supergravity field, and the ultra-small particle size nano-particles can be uniformly re-dispersed by virtue of the strong shearing of a supergravity rotating packed bed and the vibration effect of the ultrasonic field on the nano-particles, so that the amorphous ultra-small chromium hydroxide nano-dispersion capable of being stably dispersed in a solvent is prepared.
In a preferred embodiment, the surfactant comprises: one or more of sodium citrate, sodium tartrate, cetyl trimethyl ammonium bromide, polyvinylpyrrolidone, cetyl trimethyl ammonium chloride and polyethylene glycol.
In a preferred embodiment, the precipitation agent comprises: sodium hydroxide, potassium hydroxide, ammonia, sodium borohydride, and hydrazine hydrate.
In a preferred embodiment, the surfactant is present in an amount of 5 wt% to 50 wt% of the amount of chromium salt.
In a preferred embodiment, the chromium salt solution comprises: one or more of chromium nitrate, chromium sulfate, chromium chloride and chromium perchlorate.
In a preferred embodiment, the solvent is water.
In a preferred embodiment, the hypergravity reactor is a rotating packed bed.
Specifically, the process flow provided by the invention is as follows:
dissolving soluble trivalent chromium salt in water to obtain a chromium salt solution; dissolving a precipitant in water to obtain a precipitant solution;
step two, starting the supergravity rotary packed bed, pumping a chromium salt solution and a precipitator solution into the supergravity rotary packed bed through a delivery pump, reacting the chromium salt and the precipitator in the supergravity rotary packed bed and uniformly nucleating to obtain a reaction liquid containing chromium hydroxide crystal nuclei, and flowing out through a liquid outlet of the supergravity rotary packed bed;
returning the reaction liquid containing the chromium hydroxide crystal nucleus to the hypergravity rotating packed bed through a delivery pump, and circulating the reaction liquid in the hypergravity rotating packed bed for a period of time so that the chromium hydroxide crystal nucleus uniformly grows in a hypergravity environment to obtain amorphous ultrasmall chromium hydroxide;
step four, the amorphous ultra-small chromium hydroxide obtained in the step three is centrifuged and washed by water until the conductivity is lower than 200 mu S/cm;
step five, continuously dispersing the washed amorphous chromium hydroxide into water, adding a proper amount of surfactant into the washed amorphous chromium hydroxide, and stirring for a period of time at a certain temperature;
step six, centrifuging the amorphous chromium hydroxide containing the surfactant obtained in the step five, and washing with water to obtain amorphous ultra-small chromium hydroxide modified by sodium citrate;
and step seven, adding a certain amount of water into the washed sodium citrate modified amorphous state ultra-small chromium hydroxide obtained in the step six, then starting the supergravity reactor, pumping the sodium citrate modified chromium hydroxide slurry back into the reactor by using a delivery pump, and circulating in the reactor for a period of time to realize the redispersion of the nano particles, thereby finally obtaining the amorphous state ultra-small chromium hydroxide aqueous phase dispersion.
Further, preferably, the concentration of the chromium salt in the step one is 0.05mol/L to 1 mol/L.
Preferably, the molar ratio of the precipitant liquid to the chromium salt in the first step is 1: 1-1: 10.
Preferably, the rotating speed of the super-gravity rotating bed in the second step is 300-3000 r/min, and the power of the ultrasonic wave is 5-50 kW.
Preferably, the cycle time in step three is 0.5 to 3 hours.
Preferably, the certain temperature in the fifth step is 25-90 ℃, and the period of time is 1-10 hours.
Preferably, the cycle time in the seventh step is 0.5-5 h.
The present inventors have found that the process of generating chromium hydroxide by reacting chromium ions with hydroxyl groups is a rapid reaction process, and the induction time for generating crystal nuclei is usually less than 1ms, so that if it is desired to prepare chromium hydroxide nanoparticles having an ultra-small particle size with a uniform particle size distribution, it is necessary to greatly enhance the micro-mixing between chromium ions and hydroxyl groups before the nucleation of chromium hydroxide. In view of the above, the patent adopts ultrasonic coupling supergravity field to strengthen micro-mixing in the nucleation process of the chromium hydroxide, and prepares the amorphous ultra-small chromium hydroxide nano-particles. In addition, the surface modification is carried out through a surfactant, the ultrasonic field is coupled with the supergravity field to redisperse the chromium hydroxide, and the nanoparticles with ultra-small particle size can be uniformly redispersed in the water phase through the strong shearing of the supergravity rotating packed bed and the vibration effect of the ultrasonic field on the nanoparticles, so that the amorphous ultra-small chromium hydroxide nano-dispersion capable of being stably dispersed in the water phase is prepared.
Furthermore, in order to prevent blockage, the hypergravity reactor is a rotating packed bed, and hydrophobic filler is arranged in the rotating packed bed.
It can be understood that the supergravity technique, a typical process intensification technique, has been successfully applied to various industrial processes for intensifying mass transfer, heat transfer and micromixing, and has achieved excellent results, and is characterized by small equipment floor space, short retention time, high mass transfer efficiency, and rapid and efficient reaction.
The invention combines the super-gravity technology and the ultrasonic technology, applies the super-gravity technology and the ultrasonic technology to the preparation process of the amorphous chromium hydroxide dispersoid, firstly pumps a chromium salt solution and a precipitator solution into a super-gravity reactor for a set time to circulate to obtain chromium hydroxide particles; feeding ultrasound when the hypergravity reactor operates; then, surface modification is carried out on the chromium hydroxide particles by adopting a surfactant; finally, pumping the modified chromium hydroxide particles and a solvent into the hypergravity reactor to obtain an amorphous chromium hydroxide dispersoid; according to the invention, the amorphous ultra-small chromium hydroxide nano-particles are prepared by firstly adopting ultrasonic coupling supergravity field to strengthen micro-mixing in the nucleation process of chromium hydroxide, then surface modification is carried out through a surfactant, the chromium hydroxide is re-dispersed by using the ultrasonic field coupling supergravity field, and the ultra-small particle size nano-particles can be uniformly re-dispersed through strong shearing of a supergravity rotating packed bed and the vibration effect of the ultrasonic field on the nano-particles, so that the amorphous ultra-small chromium hydroxide nano-dispersion capable of being stably dispersed in a solvent is prepared.
The invention is exemplified below in a specific scenario case.
Scenario example 1
A method for preparing an amorphous ultra-small aqueous dispersion of chromium hydroxide comprising the steps of:
step one, 6g of chromium nitrate (Cr (NO3) 3.9H 2O) is dissolved in 100mL of water to obtain 0.15mol/L chromium salt solution; 6g of hydrazine hydrate (N2H 4. H2O, > 98%) was dissolved in 100mL of water to give a 1.2mol/L hydrazine hydrate solution;
step two, starting the hypergravity rotating packed bed to 1 and ultrasonic waves, setting the rotating speed to 2000r/min and the frequency of the ultrasonic waves to 50kHz, simultaneously pumping the chromium nitrate solution and the hydrazine hydrate solution obtained in the step one into the ultrasonic wave coupling hypergravity rotating packed bed through a delivery pump, reacting and uniformly nucleating the chromium salt and the hydrazine hydrate in the coupling field of the hypergravity and the ultrasonic waves, and obtaining a reaction liquid containing chromium hydroxide crystal nuclei and flowing out through a liquid outlet of the hypergravity rotating packed bed;
step three, only turning off the ultrasonic wave, pumping the reaction liquid containing the chromium hydroxide crystal nucleus obtained in the step two back to the hypergravity reactor through a delivery pump, circulating the reaction liquid in the hypergravity reactor for 1 hour, and continuously growing the chromium hydroxide crystal nucleus under the reinforcement of the hypergravity field to obtain amorphous state ultra-small chromium hydroxide slurry;
step four, the amorphous state ultra-small chromium hydroxide slurry obtained in the step three is centrifuged and washed by water until the conductivity is lower than 200 mu S/cm;
step five, continuously dispersing the washed amorphous state ultra-small chromium hydroxide into 200mL of water, adding 1g of sodium citrate into the water, and stirring the mixture for 6 hours at 50 ℃;
and step six, centrifuging the amorphous state ultra-small chromium hydroxide slurry containing the sodium citrate obtained in the step five, and washing the slurry for 2 times by using the same amount of water to obtain the sodium citrate modified amorphous state ultra-small chromium hydroxide.
And step seven, adding 40mL of water into the washed sodium citrate modified amorphous state ultra-small chromium hydroxide obtained in the step six, then starting a supergravity reactor and ultrasonic waves (the rotating speed is 2000r/min, the frequency of the ultrasonic waves is 50kHz), pumping the sodium citrate modified amorphous state ultra-small chromium hydroxide slurry back into the reactor by using a conveying pump, circulating the slurry in the reactor for 2 hours to realize redispersion, and finally obtaining the amorphous state ultra-small chromium hydroxide aqueous phase dispersion body, wherein the solid content of the amorphous state ultra-small chromium hydroxide aqueous phase dispersion body is about 4 wt% by determination.
In the figure I of the specification, a TEM image of the product of example 1 shows that the chromium hydroxide is irregular in morphology, and figure 2 is a statistical graph of the particle size distribution of the product, wherein the size distribution of the chromium hydroxide is 4-11nm, and the average particle size is about 7 nm. FIG. 3 is an X-ray powder diffraction pattern of the product of example 1, without sharp peaks characteristic of diffraction, indicating that the product of example 1 is amorphous. Fig. 4 is a photograph of the amorphous chromium hydroxide aqueous dispersion obtained in example 1 after standing for 10 months, and no delamination was observed, indicating that the dispersion had good stability. FIG. 4 is a graph showing the tendency of the Zeta potential value of the amorphous chromium hydroxide aqueous phase dispersion obtained in example 1 of the present invention to vary with the standing time, and the Zeta potential value of the amorphous chromium hydroxide aqueous phase dispersion after standing for 10 months is-43 mV, which indicates that the chromium hydroxide particles are still stably dispersed in the aqueous phase.
Scenario example 2
Under the same preparation conditions as in example 1, amorphous ultra-small chromium hydroxide dispersions can still be prepared by merely replacing the ultrasound-coupled supergravity rotating packed bed with a supergravity reactor.
In the figure of the specification, fig. 6 is a TEM image of the product of example 2, which shows that the morphology of the chromium hydroxide is irregular particles, fig. 7 is a statistical graph of the particle size distribution of the product of example 2, and it can be seen that the size distribution of the chromium hydroxide particles prepared in example 2 is 10-30 nm, and the average particle size is about 17 nm. Fig. 8 is an X-ray powder diffraction pattern of the chromium hydroxide product prepared in example 2, which still has no sharp diffraction characteristic peak, indicating that the chromium hydroxide product obtained in example 2 is also amorphous. Fig. 9 is a photograph of the amorphous chromium hydroxide aqueous dispersion obtained in example 2 after standing for 10 months, and no delamination was observed, indicating that the chromium hydroxide dispersion had good stability. FIG. 10 is a graph showing the tendency of the Zeta potential value of the amorphous chromium hydroxide aqueous dispersion obtained in example 2 of the present invention to vary with the standing time, and the Zeta potential value of the amorphous chromium hydroxide aqueous dispersion after standing for 10 months is-38.7 mV, indicating that the chromium hydroxide particles are still stably dispersed in the aqueous phase.
Comparing the results of scenario example 1 and scenario example 2, it can be seen that:
(1) the size of the chromium hydroxide particles prepared in example 1 is smaller than that of the chromium hydroxide particles prepared in example 2, amorphous ultra-small chromium hydroxide nanoparticles can be synthesized by using a super-gravity rotating packed bed, and chromium hydroxide with smaller size can be prepared by using an ultrasonic wave coupled super-gravity field to strengthen a chromium hydroxide nucleation process;
(2) after the modification of sodium citrate, the amorphous chromium hydroxide nanoparticles can be stably dispersed in the aqueous phase, while the absolute value of the Zeta potential value of the amorphous chromium hydroxide aqueous phase dispersion prepared in example 1 is lower, which indicates that the ultrasonic and supergravity coupling field is more favorable for realizing the redispersion of the chromium hydroxide nanoparticles in the aqueous phase compared with a single supergravity field.
Comparative example 1
And under the same experimental conditions of the scene example 1, stirring the mixture in a beaker to perform reaction and precipitation so as to obtain the crystalline chromium hydroxide with the size distribution of 30-150 nm.
In the figure 13 of the specification, which is a TEM image of the product of the comparative example 1, the chromium hydroxide obtained by reaction and precipitation in a beaker is observed to have a hexagonal prism shape and a size distribution of 30-150 nm. Figure 14 is an X-ray powder diffraction pattern of the product of comparative example 1 showing that the chromium hydroxide precipitated by reaction in a beaker has a high degree of crystallinity, which is in complete agreement with a standard card, and the product is crystalline chromium hydroxide. FIG. 15 is a photograph of the aqueous crystalline chromium hydroxide dispersion obtained in comparative example 1 after standing for 5 months, in which significant delamination was observed, indicating that the aqueous crystalline chromium hydroxide dispersion having a larger particle size had a lower stability than the aqueous amorphous ultra-small chromium hydroxide dispersion obtained by supergravity reaction precipitation.
Scene example 1 in comparison with the results of comparative example 1, it can be seen that:
(1) the nucleation and growth process of the chromium hydroxide is strengthened by the hypergravity coupling ultrasonic wave field, so that the amorphous chromium hydroxide with ultra-small grain diameter (average grain diameter of 7nm) and narrower grain diameter distribution range (grain diameter distribution of 4-11nm) can be prepared;
(2) after the modification of the surfactant, the effect of redispersing the nano chromium hydroxide by using the ultrasonic coupling supergravity field is better, the absolute value of the Zeta potential is larger, and the dispersion in the water phase is more stable.
The chromium hydroxide dispersions prepared in scenario example 1 and comparative example 1 were used to catalyze the thermal decomposition of ammonium perchlorate. Firstly, preparing an ammonium perchlorate/chromium hydroxide compound, which comprises the following specific steps: 1.6g of ammonium perchlorate are dissolved in 5mL of the chromium hydroxide dispersion prepared in example 1 or comparative example 1 having a solids content of 13mg/mL and are dissolved completely by heating to 50 ℃. And dropwise adding the chromium hydroxide dispersion dissolved with the ammonium perchlorate into 10ml of n-butanol under the condition of stirring, so that chromium hydroxide particles are separated out along with recrystallization of the ammonium perchlorate, and performing suction filtration and drying on the precipitate to obtain the ammonium perchlorate/chromium hydroxide compound. Testing the thermal decomposition characteristic of the compound by a synchronous thermal analyzer under the following test conditions: the heating rate was 10oC/min, the atmosphere was argon, and the gas flow was 60 ml/min. The test results are shown in fig. 14 and 15. As can be seen from the analyses in fig. 14 and 15, the decomposition peak temperature of the ammonium perchlorate was 323 ℃ and the decomposition end point temperature was 384 ℃ after the ammonium perchlorate was compounded with the chromium hydroxide dispersion prepared in example 1. After the ammonium perchlorate was compounded with the chromium hydroxide dispersion prepared in comparative example 1, the decomposition peak temperature of the ammonium perchlorate was 387 ℃ and the decomposition end point temperature was 401 ℃. The lower decomposition peak and decomposition end point temperatures indicate that the ammonium perchlorate compounded with the chromium hydroxide dispersion prepared in example 1 is more easily decomposed and has higher catalytic activity.
It can be seen that the present invention has the following effects:
1. the invention prepares the amorphous state ultra-small chromium hydroxide aqueous phase dispersion (less than 10nm) which can be stably dispersed in water for a long time by a method of carrying out reaction precipitation and surface modification by a supergravity coupling ultrasonic field. After the amorphous chromium hydroxide obtained by reaction and precipitation through the hypergravity coupling ultrasonic field is modified and redispersed by the surfactant, the Zeta potential absolute value of the dispersion is high, the dispersion can keep high stability in a water phase, and the dispersion does not settle within 10 months of standing.
2. The amorphous chromium hydroxide prepared by the invention has small particle size and narrow particle size distribution range. The transmission electron microscopic picture of the product shows that under the preferred conditions, the particle diameter distribution of the chromium hydroxide is in the range of 4-11nm, and the average particle diameter is 7 nm.
3. The process flow for preparing the amorphous chromium hydroxide aqueous dispersion is simple, the mixing efficiency of the nucleation process of the chromium hydroxide can be greatly enhanced due to the super-gravity field, the preparation process has no obvious amplification effect, and the large-scale production is easy to realize.
The embodiments in the present specification are described in a progressive manner, and the same and similar parts among the embodiments can be referred to each other, and each embodiment focuses on the differences from the other embodiments. In particular, the system embodiments are substantially similar to the method embodiments, so that the description is simple, and relevant parts can be referred to part of the description of the method embodiments.
In the description of the present specification, reference to the description of the terms "one embodiment," "some embodiments," "an example," "a specific example," or "some examples," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the embodiments of the present specification. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example.
Furthermore, the various embodiments or examples and features of the various embodiments or examples described in this specification can be combined and combined by those skilled in the art without contradiction. The above description is only an embodiment of the present disclosure, and is not intended to limit the present disclosure. Various modifications and changes may occur to those skilled in the art to which the present description pertains. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the embodiments of the present specification should be included in the scope of the claims of the embodiments of the present specification.
Claims (10)
1. A method of preparing an amorphous chromium hydroxide dispersion comprising:
pumping the chromium salt solution and the precipitator solution into a hypergravity reactor for a set circulating time to obtain chromium hydroxide particles; feeding ultrasound when the hypergravity reactor operates;
surface modification is carried out on the chromium hydroxide particles by adopting a surfactant;
pumping the modified chromium hydroxide particles and a solvent into the high-gravity reactor to obtain the amorphous chromium hydroxide dispersoid.
2. The method of claim 1, wherein the surfactant comprises: one or more of sodium citrate, sodium tartrate, cetyl trimethyl ammonium bromide, polyvinylpyrrolidone, cetyl trimethyl ammonium chloride and polyethylene glycol.
3. The method of claim 1, wherein the precipitating agent comprises: sodium hydroxide, potassium hydroxide, ammonia, sodium borohydride, and hydrazine hydrate.
4. The method of claim 1, wherein the surfactant is present in an amount of 5 wt% to 50 wt% of the amount of the chromium salt.
5. The method of claim 1, wherein the chromium salt solution comprises: one or more of chromium nitrate, chromium sulfate, chromium chloride and chromium perchlorate.
6. The method according to claim 1, wherein the solvent is water.
7. The method of claim 1, wherein the high gravity reactor is a rotating packed bed.
8. The method of claim 7, wherein the rotating packed bed is provided with hydrophobic packing.
9. The method according to claim 8, wherein the hydrophobic filler is formed with a plurality of through-holes.
10. The preparation method according to claim 9, wherein the pore passage is of micro-nano scale.
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|---|---|---|---|---|
| CN115677432A (en) * | 2022-10-13 | 2023-02-03 | 张家港楚人新材料科技有限公司 | Use of amorphous metal oxides in solid propellants |
Citations (14)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| RO100901A2 (en) * | 1988-03-30 | 1990-10-29 | Institutul De Cercetare Inginerie Tehnologica Si Proiectare Pentru Industria Anorganica Si Metale Neferoase, Bucuresti; Ro | Process of preparation of the green cosmetics pigment on chromic oxyhydrate basis |
| CN101346305A (en) * | 2005-12-27 | 2009-01-14 | 朱马国际公司 | Methods for production of metal oxide nano particles, and nano particles and preparations produced thereby |
| CN101475218A (en) * | 2008-01-04 | 2009-07-08 | 中国科学院过程工程研究所 | Method for directly preparing pigment grade chromium hemitrioxide green by using chromic hydroxide |
| CN101792167A (en) * | 2010-01-29 | 2010-08-04 | 张颖 | Method for preparing modified micro-barium sulfate |
| CN103910367A (en) * | 2013-01-06 | 2014-07-09 | 北京化工大学 | Method for preparing transparent magnesium hydroxide liquid phase dispersion |
| CN103911021A (en) * | 2013-01-06 | 2014-07-09 | 北京化工大学 | Transparent magnesium hydroxide liquid phase dispersion, preparation method and application thereof |
| CN105080436A (en) * | 2014-05-06 | 2015-11-25 | 北京化工大学 | Ultrasonic coupling supergravity rotary packed bed and application thereof |
| CN107686742A (en) * | 2017-09-27 | 2018-02-13 | 北京化工大学 | A kind of method that residual hydrogenation reaction is carried out in supergravity reactor |
| CN108047042A (en) * | 2017-12-27 | 2018-05-18 | 浙江新和成药业有限公司 | A kind of method using high-gravity technology synthesis 2,3,5- trimethylhydroquinone diester |
| CN109925993A (en) * | 2019-04-10 | 2019-06-25 | 北京化工大学 | Ultrasonic-microwave couples reaction system, the method for hypergravity and lignin degradation |
| CN109967013A (en) * | 2019-04-10 | 2019-07-05 | 北京化工大学 | Ultrasonic-microwave couples hypergravity reaction unit and system |
| CN110563018A (en) * | 2018-06-05 | 2019-12-13 | 北京化工大学 | preparation method of high-dispersion nano lanthanum hydroxide |
| CN110790306A (en) * | 2018-08-01 | 2020-02-14 | 北京化工大学 | Preparation method of monodisperse anatase nano titanium dioxide transparent liquid phase dispersion |
| CN112299467A (en) * | 2019-07-31 | 2021-02-02 | 北京化工大学 | Preparation method of monodisperse oil phase nano barium sulfate dispersoid |
-
2021
- 2021-03-29 CN CN202110331130.3A patent/CN113416433A/en active Pending
Patent Citations (14)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| RO100901A2 (en) * | 1988-03-30 | 1990-10-29 | Institutul De Cercetare Inginerie Tehnologica Si Proiectare Pentru Industria Anorganica Si Metale Neferoase, Bucuresti; Ro | Process of preparation of the green cosmetics pigment on chromic oxyhydrate basis |
| CN101346305A (en) * | 2005-12-27 | 2009-01-14 | 朱马国际公司 | Methods for production of metal oxide nano particles, and nano particles and preparations produced thereby |
| CN101475218A (en) * | 2008-01-04 | 2009-07-08 | 中国科学院过程工程研究所 | Method for directly preparing pigment grade chromium hemitrioxide green by using chromic hydroxide |
| CN101792167A (en) * | 2010-01-29 | 2010-08-04 | 张颖 | Method for preparing modified micro-barium sulfate |
| CN103910367A (en) * | 2013-01-06 | 2014-07-09 | 北京化工大学 | Method for preparing transparent magnesium hydroxide liquid phase dispersion |
| CN103911021A (en) * | 2013-01-06 | 2014-07-09 | 北京化工大学 | Transparent magnesium hydroxide liquid phase dispersion, preparation method and application thereof |
| CN105080436A (en) * | 2014-05-06 | 2015-11-25 | 北京化工大学 | Ultrasonic coupling supergravity rotary packed bed and application thereof |
| CN107686742A (en) * | 2017-09-27 | 2018-02-13 | 北京化工大学 | A kind of method that residual hydrogenation reaction is carried out in supergravity reactor |
| CN108047042A (en) * | 2017-12-27 | 2018-05-18 | 浙江新和成药业有限公司 | A kind of method using high-gravity technology synthesis 2,3,5- trimethylhydroquinone diester |
| CN110563018A (en) * | 2018-06-05 | 2019-12-13 | 北京化工大学 | preparation method of high-dispersion nano lanthanum hydroxide |
| CN110790306A (en) * | 2018-08-01 | 2020-02-14 | 北京化工大学 | Preparation method of monodisperse anatase nano titanium dioxide transparent liquid phase dispersion |
| CN109925993A (en) * | 2019-04-10 | 2019-06-25 | 北京化工大学 | Ultrasonic-microwave couples reaction system, the method for hypergravity and lignin degradation |
| CN109967013A (en) * | 2019-04-10 | 2019-07-05 | 北京化工大学 | Ultrasonic-microwave couples hypergravity reaction unit and system |
| CN112299467A (en) * | 2019-07-31 | 2021-02-02 | 北京化工大学 | Preparation method of monodisperse oil phase nano barium sulfate dispersoid |
Non-Patent Citations (3)
| Title |
|---|
| HONGYAN SHEN ET AL.: "In situ synthesis of hydrophobic magnesium hydroxide nanoparticles in a novel impinging stream-rotating packed bed reactor", 《CHINESE JOURNAL OF CHEMICAL ENGINEERING》 * |
| K J SREERAM ET AL.: "Effect of Nature of Alkali on the Zeta Potential,Colour and Particle Size Chromium(III) Hydroxide", 《JOURNAL OF SCIENTIFIC &INDUSTRIAL RESEARCH》 * |
| 吕世坪: "PEG和PVP对氢氧化铬胶体稳定性的影响", 《2008年耐火材料学术交流会》 * |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115677432A (en) * | 2022-10-13 | 2023-02-03 | 张家港楚人新材料科技有限公司 | Use of amorphous metal oxides in solid propellants |
| CN115677432B (en) * | 2022-10-13 | 2024-04-05 | 张家港楚人新材料科技有限公司 | Use of amorphous metal oxides in solid propellants |
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