基于甲酸的硝酸亚铈微波脱硝前驱体的制备

Preparation of Cerium(Ⅲ) Nitrate Microwave Denitration Precursor System Based on Formic Acid

以硝酸亚铈的硝酸溶液为原料,微波加热得到块状的固体产物,加入甲酸后继续加热可生成分散性良好的粉末状前驱体,通过X射线衍射分析(XRD)确定各步产物,并对煅烧前和煅烧后产物的粒度和形貌进行表征。结果表明,微波加热后得到块状的二水合硝酸亚铈,甲酸与其在加热条件下反应,生成棒状结构的甲酸铈。当甲酸浓度为16~20 mol/L、HCOOH/Ce摩尔比为18时,可得到粒度较为均匀的粉末。分别煅烧16 mol/L和20 mol/L甲酸制备得到的甲酸铈,煅烧后得到的二氧化铈与煅烧前的颗粒具有相同的形貌,粒径分布区间相似,但会生成一部分粒径小于0.30μm的细颗粒。

Nitric acid solution of cerium(Ⅲ) nitrate was used as raw material, and massive solid products could be obtained after heated by microwave. After adding formic acid, solid powder precursor with good dispersion could be generated by heating. The product of each step was determined by XRD, and the particle size and morphology of the products before and after calcination were characterized. The results show that the massive cerium(Ⅲ) nitrate dihydrate is obtained after heated by microwave, and the product is cerium formate with a rodlike structure after the reaction of formic acid with it. When the concentration of formic acid is 16-20 mol/L and the molar ratio of HCOOH/Ce is 18, the powders with more uniform particle size can be obtained. Cerium formate obtained under 16 mol/L and 20 mol/L formic acid are calcined into cerium dioxide, with the same morphology and similar particle size distribution range as the particles before calcination, but fine particles smaller than 0.30 μm will be generated.