Ning Liang

Preparation and Characterisation of Amorphous Silica from Alkali Wastewater Produced in Manufacturing Process of ZrOCl2

The amorphous silica was prepared from the alkali wastewater rich in Na2O•nSiO2 produced in manufacturing process of zirconium oxychloride (ZrOCl2). The composition and microstructure of amorphous silica were studied by X-ray diffraction, X-ray fluorescence and scanning electron microscope, respectively. The results showed that the amorphous silica was mainly composed of uncrystallized substance, and the silica content was 96.4%. Its whiteness was 97.5% and the particle size was between 100nm and 200nm without agglomeration. The specific surface area of the amorphous silica was 531.9 m2/g, and its pore volume and diameter were 0.945 cm3/g and 4.94 nm, respectively.

Preparation Sericite Nanoflakes by Exfoliation of Wet Ultrafine Grinding

Sericite nanoflakes were prepared by exfoliating sericite layers by wet ultrafine grinding. Their appearance morphologies and main properties were characterized. Optimum conditions were studied with the purpose of forming shear stress which was beneficial to the exfoliation of mineral flakes. The results indicated that sericite nanoflakes could be prepared. Mass ratio of grinding media to materials, diameter ratio of grinding balls, solid content of powders and grinding time had significant effects on the preparation. The thicknesses of sericite nanoflakes were 20-80 nm, and the transmittances of ultraviolet ray with wavelength of 190-220 nm were only 0.1%-1%. This demonstrated that sericite nanoflakes had the function of shielding ultraviolet ray.

Reaction Mechanism between Zn2+ and Diatomite in Preparation of Zn2+/Diatomite Antibacterial Agent

The reaction mechanism between Zn2+ and diatomite in preparation of Zn2+/diatomite antibacterial agent by diatomite adsorbing and solidifying Zn2+ in its pores was studied. Microporous adsorption, characterized by hydrated Zn2+ adsorbed in the micropores of diatomite, and surface coordinate adsorption, featured with coordination of Zn2+ with functional groups on the surfaces of diatomite, were the main adsorption ways accompanied by ion exchange adsorption and physical adsorption. SEM was used to observe the morphologies of diatomite before and after adsorption. Due to the dehydration between OH groups on the surfaces of diatomite when heat treated at high temperature, Si-O-Zn bonds were formed, combining Zn2+ with diatomite together. Reaction model between Zn2+ and diatomite was established.

Activation of Natural Zeolite and its Adsorption Property

Activation methods to improve the adsorption property of natural zeolite by inorganic acid and heat treatments at high temperature were investigated and its function of adsorbing harmful gases was evaluated. The results show that both methods can improve the adsorption property. Natural zeolite which was heat treated for 24 h has an adsorption ratio of 14.67% to H2O in air, which indicates the remarkable improvement of adsorption property. Meanwhile, the adsorption ratios to simulated refrigerator smelling gas such as NH3 and H2S after 10 min are 99.00% and 95.20%, respectively.

Effect of Modification by WTP-08 on Dispersity of Nanosized CalciumCarbonate and Its Mechanism

The dispersity of nanosized calcium carbonate modified by alkyl amine dimethyl phosphonic acid (WTP-08) through mechano-chemical method in different media was investigated. The modification mechanism was investigated by analyzing the surface energy and its thermodynamic effect on dispersity of nanosized calcium carbonate. The results show that the free energies of nanosized calcium carbonate modified by WTP-08 and its interfacial free energies in air and non-polar media decrease significantly, while the interfacial free energy in water increases remarkably. It can be concluded that modification by WTP-08 improves the dispersion tendency of nanosized calcium carbonate in air and non-polar medium, while it decreases in water. Therefore, modification by WTP-08 makes the dispersity of nanosized calcium carbonate increase in air and non-polar medium and decrease in water.

Preparation and Properties of Zn2+/Diatomite Antibacterial Agent

. Zn2+/diatomite antibacterial agent was prepared by diatomite loading and solidifying Zn2+ in its holes through ion exchange and heat treatment at high temperature. Influencing factors on its preparation were discussed. Antibacterial property and durability were characterized by measuring the diameters of inhibition rings and the minimal inhibitory concentrations (MIC). Whiteness and antibacterial property of the paint filling it were also tested. The results show that the agent has excellent antibacterial property and durability. The diameters of inhibition rings are larger than 10 mm even after 7 days. MIC is 312 g/mL and it is still low enough after durability test. The paint adding only 0.5% of it also has good antibacterial property while declining the whiteness slightly.

Study on Preparation of Zeolite/Ag+ Composite Particles Material and Its Air Purification Property

Zeolit/Ag+ composite particles material (ZACPM) had been prepared using zeolite as carrier by carrying Ag+, solidifying Ag+ stably in the holes of zeolite and enhancing the adsorption property of zeolite. The effects of technological parameters on preparation of ZACPM, the air purification properties such as antibacterial property and the function of eliminating harmful gases and the microstructure of ZACPM were studied. The results indicated that Ag+ is carried in zeolite by ion exchange and solidified stably in the holes of zeolite and its adsorption property is enhanced by roasting ZACPM at high temperature. ZACPM has excellent self-cleaning and antibacterial properties. The concentration of bacteria is smaller than 1cfu/mg and the antibacterial ratio is 100% after reacting with 105 colibacillus for 24h. The eliminating ratios of NH3 and H2S are both over 99% after reacting for 30min and 10min, respectively. Ag+ distributes homogeneously in the holes of zeolite and some free holes were also existed.

Preparation of Zn2+/Stilbite Composite Particles Material and its Antibacterial Property

Zn2+/stilbite composite particles material was prepared by stilbite carrying Zn2+ and solidifying Zn2+ stably using natural stilbite as carrier. The physical properties such as particle size and whiteness, the functional properties such as antibacterial property, durability and the behavior of eliminating harmful gases, and the microstructure of Zn2+/stilbite composite particles material were investigated. The average particle size of Zn2+/stilbite composite particles material is 0.8mm, and its whiteness is 88, and the whiteness of the paint adding it isn’t influenced. Zn2+/stilbite composite particles material has excellent antibacterial property and durability. The restricting ratio against Escherichia coli and staphylococcus are both 100% when the concentration of Zn2+/stilbite composite particles material is 700mg/mL, and the restricting ratios are still 99% and 98.5% after it dipped into hot water for 12 hours, respectively. Zinc ions distribute homogeneously in part holes of stilbite and there are still many free holes in stilbite, which makes Zn2+/stilbite composite particles material have the function of eliminating harmful gases as well.

Effects of Heat Treatment on Crystal Structure and Reactivity of Sericite

To activate the reactivity of sericite and make it have the abilities of ion exchange and intercalation between layers, the effects of heat treatment on crystal structure and reactivity of sericite were studied. The results, analyzed by XRD and Hall formula, indicate that sericite still retains its crystal characteristics after being activated by heat treatment at 500°C-800°C, but there are significant lattice distortions, and the maximum one occurred at 800°C. It can be seen from the SEM images that heat treatment reduces the order of sheets of sericite and makes the surfaces rough and the edges and corners smooth. The Al3+ dissolution amount from the sericite in HNO3 is 24.34 mg/g after heat treatment, which is increased significantly compared with the untreated one. It demonstrates that the reactivity of sericite is improved remarkably.

Preparation and Characterization of Tourmaline/TiO2 Composite Particles Material

The preparation of tourmaline/TiO2 composite particles material (TTCPM) by mechano-chemical method and its performance were studied in this paper. The results show that tourmaline/TiO2 composite particles material can be prepared by the surface modification of tourmaline using TiO2 as a modifier with wet ultra-fine grinding tourmaline and TiO2 together after tourmaline is ground to required size. The modification effect and performance of TTCPM are influenced by the dosage of TiO2, the pulp concentration and the grinding condition under which the mechanical forces can be produced. Comparing the properties of the TTCPM with that of tourmaline, negative ions quantity does not change and whiteness increases remarkably. In addition, the properties of pigment, such as hiding power, are added.