Fabrication And Properties Of Ceramics Using Leaching Residual Slag Of Lepidolite Ore

Lithium resource is an important part of new energy industry.However,the precision of domestic lithium ore is so low that a large amount of solid waste is often produced in the process of lithium refining.Reasonable resource utilization of these solid wastes can not only respond to national environmental protection requirements to save resources and reduce pollution,but also turn waste into treasures and produce greater social and economic benefits.Therefore,taking leached lithium mica slag（hereinafter referred to as lithium slag）as the main research object,the preparation of lithium slag based porous ceramic materials with good performance by introducing mechanism sand and different additives which can provide a new way for the resource utilization of lithium slag,which has good practical value.This paper deals with the preparation and properties of lithium slag based porous ceramics with high strength and low thermal conductivity.Using lithium slag and low grade feldspar as raw materials and silicon carbide（Si C）as foaming agent,lithium slag based porous ceramics were prepared by high-temperature foaming method.The effects of sintering parameters,lithium slag content and Si C dosage on the properties of lithium slag based porous ceramics were studied.A certain degree of increase in the sintering time and temperature is beneficial to the preparation of porous ceramic materials with excellent properties.In order to further enhance the properties of lithium slag based porous ceramics,mechanism sand replacing part of feldspar and different additives of magnesium oxide（Mg O）,calcium oxide（Ca O）and light calcium carbonate（Ca CO₃）were used to prepare lithium slag based porous ceramics with high strength and low thermal conductivity,respectively.The effects of mechanism sand and additives on the properties of lithium slag based porous ceramics were systematically studied.The results show that mechanical sand replacing feldspar can improve the compressive strength of ceramics and increase the utilization rate of lithium slag,while Mg O,Ca O,and Ca CO₃ additives can improve the pore structure of ceramics and change the crystal phase composition of ceramics,so as to reduce the volume density of ceramics,and then reduce the thermal conductivity of lithium slag based porous ceramics.