| SB A-15 mesoporous molecular sieve has been widely used in the field of catalysis, adsorption, because of its large aperture, high specific surface area, good thermal stability.Rhodamine B as cationic alkaline dye, is widely applied to areas such as food, paper making, printing and dyeing. However, rhodamine B is carcinogenic and very adverse to human body, so it is imperative to get rid of rhodamine B in waste water, and adsorption method is one of the effective methods of treatment of dye wastewater. Phenol is an important intermediate for the production of petrochemicals, agrochemicals and plastics. Most phenol worldwide is produced via the three-step cumene process from benzene.The disadvantages of the cumene process have stimulated the development of alternative routes to decrease energy consumption, increase the yields and avoid the byproduct acetone. It does not accord with sustainable development strategy. No matter from the point of view of economy and environment, the one-step direct hydroxylation of benzene toward phenol use clean oxidant has been a hotspot in the field of catalysis.At present, most of the research is based on ethyl orthosilicate (TEOS) as the silicon source to synthesize SB A-15, but TEOS is expensive,it is not conducive to industrial production of SBA-15. Many studies suggest that vanadium, iron catalyst in hydrocarbon and oxidation reaction of benzene toward phenol showed high catalytic activity. From now on, the research of vanadium and Fe incorporated SBA-15, through one-step direct hydroxylation of benzene toward phenol use H2O2 has not reported, so this article mainly introduced the experimental research in this aspect.Our main research contents are in the following.1. SBA-15 molecular sieve was synthesized by a conventional hydrothermal synthesis method using cheap non-toxic Na2SiO3 as silica source to replace traditional ethyl orthosilicate (TEOS) and nonionic triblock copolymer P123 as the template. The effects of the experimental conditions on the crystal structure and yield of SBA-15 were examined. The results show that the SBA-15 molecular sieves is two-dimensional six square, framework arranged alternately, the regularity of the channel is good, and it is homogeneously dispersed spherical particles. At the same time, the rhodamine B adsorption properties of SBA-15 were subsequently investigated.Adsorption rate of SBA-15 is as high as 99.9%, showing the excellent adsorption performance of rhodamine B.2. Fe-V/SBA-15 catalyst was synthesized by grafting synthetic method. The catalyst was used to investigate the benzene catalytic performance, and phenol was fabricated from benzene by H2O2 one-step hydroxylation. The effects of reaction conditions on the catalytic performance were studied systematically. The results show that the Fe-V/SBA-15 showed a good catalytic performance, benzene conversion rate was 23%, the selectivity of phenol is 94% under the optimum reaction conditions.3. A series of V and Fe incorporated SBA-15 samples were successfully synthesized. The samples were characterized using XRD?FTIR?SEM?TEM? XPS and tested in the catalytic performance of benzene. Determine the Fe(0.77)-V(0.94)/SBA-15 samples of benzene catalytic performance is optimal, benzene conversion rate is 31.31%, phenol selectivity up to 92.87%. Fe.0.77)-V (0.94) /SBA-15 samples kept a good two-dimensional six-party structure, specific surface area was 356.436 m2·g-1, pore volume was 0.603 cm3·g-1, the average pore size was 3.57 nm. |
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