| Opaque glass widely used in the construction, bottles, containers, art, ornaments. We commonly used emulsifying agent for the fluoride, such as fluorite, sodium fluosilicate, ryolite, aluminum fluoride, potassium fluoride. When raw materials processing, melting, forming, machining and other processes, fluoride dust and volatile matter can make environmental pollution, such as in the process of melting the volatilization of fluoride can be up to 25%-35%. As we all know, fluoride can cause acute and chronic human toxicity, if people inhaled NaF, CaF2, Na3Al3F6 dust cause pneumoconiosis and then maybe can make the lung sclerosing later; fluoride cause respiratory tract, nasal, conjunctival, teeth, skin injuries, also occurred dizziness, headache, weakness, limb and back pain, loss of appetite and other symptoms, even death.China's relevant departments under the production environment to allow fluoride limits in air for the 2mg/m3, the existing maximum allowable emission sources of fluoride concentration is 11mg/m3,and the new is 9.0mg/m3.So, Fluoride opaque glass production company has taken a series of measures to prevent fluorine pollution. But it is a temporary solution and if we want to control the fluoride pollution,we must use opaque glass with fluorine-free.On the one hand development of fluorine-free glass in developed countries on the other hand contaminated by the transfer the fluoride opaque glass production to developing countries, but no longer in their own local production of fluorine opaque glass. Some factories in China accept foreign fluoride opaque glass cups and plates, containers, decorations and mosaic production orders. In accordance with the scientific concept of development, we can no longer expense of the environment to economic development, and we must conserve resources, protect the environment, environmental pollution from the source. So the development of fluorine-free opaque glass has great significance.In this paper, we study on phosphate as emulsifying agent. Choosing Ca3(PO4)2 for the study on how to prepare of fluorine-free opaque glass and conducted in-depth analysis and discussion. To raw materials,we choose Ca3(PO4)2,CaO,ZnO,Na2CO3 to do zhe orthogonal experiment which has 4 factors and 3 horizons which using to research the best formula. Its whiteness is 67, and the original sample whiteness is 49. After adding phosphate emulsifying agent, emulsion effect is obvious. Add the cream emulsion agent on glass hardness, chemical stability, thermal expansion coefficient and the friction and wear tests to demonstrate the performance of opaque glass after full compliance with relevant requirements.Original samples for acicular crystals of mullite and a small amount of quartz, particle diameter near 0.4-0.75um. Crystal has a strong scattering to the visible light so improve the whiteness.Study on technological conditions such as sintering temperature holding time and the particle diameter which impact the whiteness. When sintering temperature is 1350℃,hold for 80 minutes and the particle diameter near 0.4-0.75μm lead the opaque glass with high whiteness.
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