基于高铝粉煤灰的堇青石-莫来石复合材料制备

Preparation of cordierite-mullite composite from high-alumina coal fly ash

为了实现高铝粉煤灰的高值化利用,以高铝粉煤灰为单一铝硅原料,依次对其进行酸、碱预处理,将处理后的高铝粉煤灰与滑石粉混合,通过一步原位烧成制备堇青石-莫来石复合材料,进一步考察原料配比和烧成条件对烧成样品性能的影响规律。结果表明,烧成温度为1 370℃、烧成时间为2 h、堇青石和莫来石理论质量比为50∶50时,可制备出体积密度为1.96 g/cm^3、显气孔率为30.47%、常温抗折强度为66.44 MPa的堇青石-莫来石复合材料,其主要指标均达到YB/T 4549—2016《堇青石-莫来石窑具》的要求,该方法实现了以粉煤灰为主要原料,灵活制备具有不同堇青石和莫来石配比的复合材料,为高铝粉煤灰的高值化利用提供新途径。

In order to realize the high value utilization of high-aluminum coal fly ash（HAFA） , HAFA was treated with acid solution and alkaline solution in sequence, subsequently the pretreated HAFA mixed with talcum power and then calcined to prepare the cordierite-mullite composites. The effects of raw materials ratio and calcination conditions on the properties of calcination products were studied. It is found that the eordierite-mullite composite with bulk density of 1.96 g/cm^3, apparent porosity of 30.47% and bending strengths of 66.44 MPa could be successfully prepared when the raw materials＂ theoretical mass ratio of cordierite to mullite is 50 ： 50, the calcination time is 2 h and the calcination temperature is 1 370 ℃. The properties of the product meet the requirements of the standard of cordierite-mullite kiln furniture （YB/T 4549--2016） ,which provides a new approach to transfer HAFA into high-value products.