对细菌合成晶种和化学法(不含细菌)合成晶种的催化性能进行研究。扫描电子显微镜和X射线衍射分析显示,生物合成的晶种表面光滑,主要由黄钾铁矾组成,化学法合成的晶种具菜花结构,主要由草黄铁矾组成。相对化学法晶种,生物法晶种催化性能更优,诱导期缩短至20 min,温度降至75℃,初始速率增加显著,达到3.933%/min。采用生物法晶种的除铁沉淀结晶度高达97.22%,而不含晶种时结晶度仅为12.89%,这表明生物法晶种可使铁矾沉淀转化更完全。
The catalytic performance on jarosite process of jarosite seeds via biosynthesis and chemical processes were studied, respectively. The SEM and XRD results showed that biosynthetic jarosite seeds (BIO seeds) had smooth surface and mainly consisted of potassium jarosite. The chemical synthesis jarosite seeds (CHM seeds) had a loose cauliflower-like surface and mainly consisted of hydronium jarosite. The catalytic performance of BIO seeds was better than that of CHM seeds on the formation of final jarosite product. The induction time can be shortened to 20 min, the reaction temperature can be reduced to only 75 ℃, and the initial reaction speed was enhanced obviously, up to 3.933%/min. The crystallinity of final jarosite product using BIO seeds can achieve 97.22%, while it was only 12.89% without seeds. This indicates that the precipitation process of jarosite is more complete with BIO seeds.