Gu Xiaohua, Chen Peiquan, Wang Tong, Liu Siwen, Zhu Shangwen, Zhu Yanwei, Liu Yan
School of Energy and Building Environment, Guilin University of Aerospace Technology, Guilin 541004, China.
State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Materials Science and Engineering, Donghua University, Shanghai 200051, China.
Nanomaterials (Basel). 2023 Mar 23;13(7):1143. doi: 10.3390/nano13071143.
A large amount of catalyst waste containing silicon is deposited or buried every year, resulting in serious environmental pollution and a waste of resources. In this paper, a method to prepare mullite whiskers by recycling silica-rich waste under low-temperature conditions was investigated. The effects of raw materials, sintering temperature, catalyst addition, holding time and co-solvent addition on the structure, morphology and phase transition of the synthesized whiskers were investigated and characterized with SEM, XRD, TEM, TG and DTA. The results show that the addition of 10% NaSO as the liquid-phase mass transfer medium could effectively improve the crystallization efficiency of mullite whiskers, while providing an ideal living environment for the growth of whiskers. The crystallinity and uniformity of mullite were positively correlated with the addition of aluminum fluoride trihydrate and the holding time, respectively. The growth law and conditions of mullite whiskers are discussed, and the optimal growth process conditions of mullite whiskers were optimized. The optimal conditions for mullite whiskers were determined as follows: the addition of aluminum fluoride is 5 wt%, the sintering temperature is 825 °C, and the holding time is 5 h at the time of sintering. This work offers new prospects for the industrial production of mullite whiskers from recycled silica-rich waste.
每年都会有大量含硅的催化剂废料被堆放或掩埋，这导致了严重的环境污染和资源浪费。本文研究了一种在低温条件下通过回收富硅废料制备莫来石晶须的方法。研究了原料、烧结温度、催化剂添加量、保温时间和共溶剂添加量对合成晶须的结构、形貌和相变的影响，并用扫描电子显微镜（SEM）、X射线衍射仪（XRD）、透射电子显微镜（TEM）、热重分析仪（TG）和差示热分析仪（DTA）进行了表征。结果表明，添加10%的NaSO作为液相传质介质可以有效提高莫来石晶须的结晶效率，同时为晶须生长提供理想的生存环境。莫来石的结晶度和均匀性分别与三水合氟化铝的添加量和保温时间呈正相关。探讨了莫来石晶须的生长规律和条件，并对莫来石晶须的最佳生长工艺条件进行了优化。确定了莫来石晶须的最佳条件如下：氟化铝添加量为5 wt%，烧结温度为825℃，烧结时保温时间为5 h。这项工作为从回收的富硅废料中工业化生产莫来石晶须提供了新的前景。
