Study On Synthesis Of Nano TiO₂-coated Attapulgite Composites And Its Photocatalytic Decomposition Of Organic Pollutions

The special superiority of light catalyst technology exhibited when coped with venomousness and hard degradation organic contaminant. Nano-TiO₂ is used as outstanding light catalyst because of its stable low-dissolve and low cost properties, so it applies in air purifying sewage disposal and sterilization. On the other hand, layer-shape compound has the special micro-hole structure and ion exchange capability, is widely used as catalyst carrier. In this paper, to solve the contradiction between catalyst fastness and activation in its real application, firstly utilizing the method of acid sol-gel to synthesize TiO₂/ATP compound catalyst to utilize the high specific surface area and sloth adsorbent attapulgite as a carrier It is one of the productive method of increasing the photocatalytic activity and rapidly adsorb and purify the low content contamination in the water, at the same time qucikening the photocatalytic velocity. The effects of preparing conditions on the physical characterization and the photoactivity were investigated. Moreover, the photodegradation of formaldehyde were also discussed in detail.A series of investigation were carried on synthesize . characterization and light activation of the TiO₂/ATP by applying the method of acid sol-gel. Using X-ray diffraction(XRD), scanning electron microscopy(SEM),differential thermal analyzer (DSC-TG) and infrared spectrum(IR) by analyzing the catalyst's composition, size and structure. Results showing that: the addition of attapulgite can effectively restrain the grow-up of TiO₂ grain and its transition; the particle size in the compound is smaller than pure TiO₂ with the same process, moreover, the transition temperature of anatase phase to rutile phase improve about 400°C; The attapulgite in the composites still keeps the original crystal structure under 450℃calcining temperature; There is no finding in the Si-O-Ti bond illustrating TiO₂ is only coated onThe photodegradation of formaldehyde is discussed in this paper, which situated on the second on our country's' pre-controlling chemical poisono Results showing that: When the sample was treated below 850℃, the concentration of formaldehyde was less than 5mg/L and the degrationg rate on the formaldehyde can amount to 98% in two hour; The photoactivity of the nanocomposite was much higher than that of pure titania in case of the same amount of titania and subside performance obviously.So far, there is little report on the compound degradation of hard-solvable organic contaminant. The light catalyst technology refers to the spheres of chemistry, energy, environment. From the point of its developing course it can be concluded that the catalyst will be playing an important role in the degradation of organic contaminant.