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With the rapid economic development of our society, the growing problem of arsenic contamination. As arsenide have greater toxicity and in industrial and agricultural production has been widely used, arsenic pollution of the environment especially for water pollution, has caused environmental scientists worldwide attention. At present, China underground water in some areas high levels of arsenic in the background value has exceeded the maximum allowed value of drinking water for local residents caused serious harm. According to reports, through a variety of ways to enter the arsenic in the hydrosphere, the world each year about 110,000 tons. Therefore, in our study arsenic wastewater treatment is important. Adsorption method is a simple waste water treatment technology, with high efficiency, simplicity and good selectivity, especially for low concentrations, pollution resistance, other methods of waste water containing arsenic is difficult to effectively deal with a unique application value. But now widely used in industry inefficient arsenic removal adsorbent, so the development of efficient adsorption of arsenic treated adsorbent is an important research direction. Mesoporous molecular sieve having a large specific surface area, pore structure and pore size is easy to adjust the rules, thermal stability and hydrothermal stability, good surface easily modified, etc., so in catalysis and adsorption separation chemistry and other areas of great potential value . In this thesis, mesoporous SBA-15 research mainly includes the following two parts: (a) Comparison of the adsorbent screening experiments using the template synthesis of research first mesoporous SBA-15 and MCM-41, and then with an equal volume impregnation method its modification. The modified adsorbent and commercial alumina, zeolite and clinoptilolite Hui comparative study. The results showed that: in the initial concentration of arsenic 44.703mg / 1 or 11.176mg / l, pH = 6.60, temperature 25 ± 1 ℃, 0.2g adsorbent experimental conditions, mesoporous MCM-41 and SBA-15 basically does not adsorption of As (V); MCM-41 and SBA-15 modified materials and commercial alumina, zeolite clinoptilolite and pyroxene comparison found that the adsorbent 400 ℃-SBA-15-10% Al for As (V) The best adsorption. (2) on the adsorbent 400 ℃-SBA-15-10% Al research studied under static conditions adsorbent 400 ℃-SBA-15-10% Al for arsenic removal. Also investigated the pH value of the adsorption time, the initial arsenic concentration, adsorption temperature, the amount of coexisting ions and the adsorbent on the adsorption process. The results showed that: the solution pH, adsorption time, initial concentration, adsorption temperature, coexisting ions and adsorbent dosage on the adsorption process in varying degrees. Adsorbent 400 ℃-SBA-15-10% Al in a wide pH range (2.17 - 8.16) to As (V) showed strong adsorption capacity, maximum absorption rate in the vicinity pH = 6.60, the value 85.23%; With the As (V) initial concentration increased, 400 ℃-SBA-15-10% Al for As (V) removal decreased, while As (V) initial concentration of 223.515mg / l when adsorption rate is very low; adsorbent dosage is affecting the adsorption rate is another important factor, as the adsorbent dosage increases, arsenic adsorption rate rising rapidly; short adsorption temperature increases, the adsorption rate increases rapidly, 540min and the temperature change rate of absorption decreases; NO3-, Cl-, SO42-, F-, PO43-such as the presence of interfering ions decreased the As (V) adsorption rate, where the interference of the strongest PO43-, followed by F-, NO3-, Cl-, SO42-, plasma considerable degree of influence on the adsorption. Finally, the powder X-ray diffraction (XRD), scanning electron microscopy (SEM), N2 adsorption - desorption, transmission electron microscopy (TEM) techniques were used to characterize the material means. The results showed that aluminum was successfully introduced within the pores of SBA-15 did not cause the collapse of the skeleton, and the synthesis of modified mesoporous molecular sieve has a good mesoporous pore structure.
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