硅藻土掺杂钨渣制备多孔陶粒及其性能研究

Preparation and Performance of Porous Ceramic from Diatomite with Waste Tungsten Residue

为充分利用我国粘土资源和消除排放量巨大的钨渣对环境造成的污染,以硅藻土为基质材料,固体废弃物钨渣为辅料,采用添加造孔剂法制备多孔陶粒材料,研究了造孔剂添加量和烧结温度对其性能的影响。通过X射线衍射仪和扫描电子显微镜等分析技术对试样进行了性能表征。结果表明:随着复合造孔添加量的增加,气孔率、吸水率和粉化率也随之增加,密度则下降。烧结温度的提高则可以有效的降低粉化率,并且多孔陶粒材料的主要物相组成基本不变。而当烧结温度高于1075℃时,气孔率和吸水率会显著下降。造孔剂添加量为40%,烧结温度为1000℃时,可制得粉化率较低、气孔发达的多孔陶粒吸附材料。将在最佳工艺条件下制取的多孔陶粒对氨氮废水进行吸附试验,在300 min时单位吸附量可达1.3 mg/g。

In order to take full advantage of clay resources and eliminate the pollution of Tungsten residue on environment in China, porous ceramics were prepared from diatomite as matrix material with solid waste Tungsten residue as auxiliary material by adding a pore-making agent. Effects of the amount of the pore-making agent and sintering temperature on properties of the porous ceramics were studied. The properties of specimens were characterized by X-ray diffraction （XRD） and scanning electron microscope （SEM）. The results showed that with the pore-making agent increasing, the porosity, water adsorption and thepulverulent ratio increased, but the density decrease. Increasing of the sintering temperature can decrease the pulverulent ratio of the porous ceramics, moreover, the main phases in the porous ceramics are similar at different sintering temperatures. When the sintering temperature was above 1075 ℃ , the porosity and water adsorption decreased significantly. When the amount of the pore-making agent was 40% and the sintering temperature was 1000 ℃ , the porous ceramic materials have low pulverulent ratio and high porosity. Adsorption test of ammonia-nitrogen wastewater was implemented on the porous ceramic prepared under the optimum conditions, and the unit adsorption capacity can reach 1.3 mg/g at 300 min.