摘要
采用喷雾干燥-固定床法制备碳化钨粉末，研究了喷雾干燥和碳化反应温度对制备偏鸽酸铵前驱体以及碳化钨的影响，前驱体粉末呈现均匀的球状形态，平均粒径为10-20μm。喷雾温度对影响粒径大小和分布影响小；400℃的进口温度下进行喷雾干燥，喷雾粉末仍然保持偏钨酸铵原来的基本组成不发生分解。以H2／CO为还原碳化介质，在900℃的温度下还原碳化前驱体，制备得到碳化钨粉末，粒径为0．5～2．0μm，比表面积为6．5m^2／g；比较传统的制备碳化钨的实验方法，降低了制备碳化钨的反应温度；颗粒比表面积大，可作为催化剂应用于加氢反应、烷烃裂解、催化重整以及燃料电池等领域。
WC powder was prepared by the combination of spray-drying and fixed bed technology. The effects of the spray-drying process of the ammonium paratungstate and the carburization temperature on the format.ion of the precusor and WC powder were investigated. The results show that the precursor powder is homogeneous and spherical with an average diameter of 10-20μm. The spray-drying temperature has no obvious influence on the size and distribution of the precursor particles. The composition of the powder spray-dried at 400℃ is the same as that of the ammonium paratungstate, indicating that no decomposition reaction occurs. The diameter of the WC powder prepared by carbonizing the precursor with H2/CO at 900℃ is about 0.5-2.0μm with a specific surface area of 6.5m^2/g. Compared to the traditional preparation methods, the spray-drying and fixed bed technology decreases the preparation temperature and the WC powder as-produced has higher specific surface area. It is suited to be used as catalyst in hydrogenation, reforming, cracking reactions etc.
出处
《化学世界》
CAS
CSCD
北大核心
2006年第2期71-73,87,共4页
Chemical World
基金
浙江省自然科学重大基金项目(200024)
关键词
喷雾干燥
偏钨酸铵
碳化钨
spray-drying
ammonium paratungstate
WC
