| Nano-material is a kind of new material which has extensive application prospect, and it is considered as new material of twenty-one century. The main materials making up of nano-material are nanometer particle, and their sizes are in range of 1 to 100 nanometers. Nanometer alumina has high intensity, high rigidity, heat resistant, corrosion resistant characteristics and so on. Because the number ratio of its surface atoms and body phase atoms increases rapidly along with decreasing of particle size, it shows intensive volume effect (small size effect), quantum size effect, surface effect and macroscopic quantum tunnel effect, then it exhibits a series of excellent properties in light, electric, thermodynamics, chemical reaction and many aspects. Thus, nanometer alumina has wide application prospects in ceramic material, catalyst, electronic industry, coating material, biological medicine and optical material aspects etc. The application of high purity, ultra-fine, highly active, particle size distribution centralized and agglomeration force low nanometer alumina powders not only can decrease sintering temperature greatly and save energy, but also can obtain fine crystalline granularity and high induced density products.Mesoporous alumina which has extensive application prospect in industry is widely used as catalyst material, for example, acid catalyst, catalyst supports and so on, as well as, it is used in adsorption and separation applications. While it is being used in these aspects, the pore structure performance and specific surface area of alumina are the most pivotal.In 1992, scientists of Mobil Company synthesized silica-based mesoporous molecular sieves of M41S family for the first time under alkalescence condition and they used quaternary ammonium salt type cationic surfactant as templet. From that time, mesoporous material became one pop problem in catalyst materials researching field. Mesoporous material is a new kind of porous material, which has rule arranging pore structure, and its aperture can continuously adjust in range of 2~50nm.There was report that aluminum went into framework of mesoporous silicon oxide soon after the discovery of M41S family. Subsequently, mesoporous alumina was synthesized successfully, too. Alumina mesoporous material has more narrow pore size distribution and it has more high specific surface area than transition alumina, so it is more propitious to catalyst application in cosmical industrial process.Today when the high quality land clay resource dries up increasingly, exploitation and utilizing of abyssal clay resource has become a head and long-term meaning research direction. Compared with land clay, abyssal clay holds many particular features, for instance, fine granule, worse crystallization, high activity etc. And, it also holds many shortcomings as complex mineral and chemical components,and low whiteness etc., which influence its using. Clay mineral which makes up of abyssal clay aggradation substance having low crystal degree and incompact structure are its typical characteristics. Based on performance amelioration of abyssal clay going along purification, this dissertation just utilize its structure characteristic while avoiding its disadvantages, and adopt reasonable method would all kinds clay mineral structure open up effectively, compound again, wipe off impurity ions, and finally prepare nanometer and mesoporous alumina materials.Preparing nanometer aluminum process by abyssal clay is that ammonia as precipitator was added into filtrate after preparing amorphous silica, and separated out sedimentation from the filtrate under definite conditions, then added superfluous sodium hydroxide solution into the sedimentation gained from filtrating in order to Aluminum hydroxide sedimentation inside can dissolve renewedly, filtrated again, collected filtrate, afterward superfluous carbon dioxide gas was added into the filtrate, in order to AlO2- inside can hydrolyze adequately and become Aluminum hydroxide sedimentation, whereafter filtrated, washed, dried and calcined under high temperature, finally we can gain production alumina.Production obtained from preparing nanometer alumina by precipitation method isα- alumina primarily, and has a small quantity ofδ- alumina. Its pure degree is close to 100%. Better crystal grains show pole shape. If definite quantity polyethylene glycol 6000 as dispersant is added when experiment, grains of production will become exiguous, granularity can attain 10nm around, and recovery quotiety can arrive at 95.87%, but specific surface area of production is very small.Using abyssal clay as raw material, based on obtaining pure Aluminum hydroxide sedimentation from recovering aluminum by precipitation method, the optimal technical conditions that preparing mesoporous alumina by sol-gel method are as follow: dissolved 1.5g of templet into100mL of 0.5mol/L ammonia solution, stirred equably and heated up to 75℃, then 33mL same consistence aluminum nitrate solution was slowly dropped into above solution and stirred fiercely at the same time, 1mol/L nitric acid and 1mol/L ammonia solution was used to adjust PH value of the mixture after 1h, and then gained steady and transparent gelatin after being stirred at the constant temperature 75℃, afterwards, aged 48h at the room temperature, subsequently, dried into dry gelatin in oven at 80℃, the finally, a temperature ramp rate of 1℃/min from room temperature to 250℃was used, and then maintained the temperature for 1.5h in air in order to C-H chain of templet can rupture fully, and calcined at 500℃for 2h, ultimately, we obtained pure production mesoporous alumina. And using cetyltrimethylammonium bromide and urea as mulriple templet can increase the specific surface area of production, especially, when the quality ratio of cetyltrimethylammonium bromide and urea is 1:1, the effect is best.Preparing mesoporous alumina by sol-gel method, the infrared ray curves of production obtained haven't other absorbtion cingulum, we take for the production is pure. The nitrogen adsorption-desorption isotherms belong to LangmuirⅣtype. There is a obvious hysteresis loop in the range of the relative pressure between 0.4~0.8, which indicates the substance has more regular mesoporous pore structure, and the aperture centralizes about 3.6nm. The X-ray diffraction figures of samples before and after being calcined all only appear characteristic diffraction apex corresponding to 100 crystal surface in the range of low angel that 2θbetween 0.5°~3°, the position of 2θis around 0.85°. In the range of wide angle, they all have not obvious diffraction apex, which shows that the production gained is short range order and long range disorder mesoporous alumina material, and there are lots of disorder disposed wormhole structures in the products mesoporous alumina.
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