铁氧体-高压水解一步除氰、镍的机理研究

THE REACTION MECHANISM OF REMOVING CYANIC AND NICKELIC COMPOUNDS WITHIN ONE PROCESS

本文研究了在1.013MPa,180℃条件下,废水中CN^-,NH_3,Ni^(2+)并存时,以形成铁氧体同时进行高压水解一步除氰、除镍的反应机理.结果发现,镍铁氧体的形成是由于镍离子取代了Fe_3O_4中的两价铁的晶格位置形成的,新生态的Fe_3O_4具有表面吸附作用,但随着反应时间的延长吸附量会有所下降;氰水解是镍形成铁氧体的前提,为含氰、含镍废水在高压水解条件下铁氧体一步法治理奠定了理论基础.

It was studied in this article that the reaction mechanism of removing cyanic and nickelic compounds within one process by forming ferrites and highly pressured hydrolysis under the conditions of pressure 1.013MPa and temperature 180 C ,when the nickelic, cyanic and ammoniacal compounds coexisted in wasterwater. The results showed that the Ni-ferrites was formed by Ni2+ ion replacing the lattice site of Fe2+ ion in Fe3O4. The suspended solids, such as Ni(OH)2, NiO, could be absorbed on the surface of the newly produced Fe3O4, but the absorption efficiency would be decreased as increasing the reaction time. It is very important that cyanide and its complex should be hydrolyzed as the essential prerequisite for forming the Ni-ferrites. This study lays the theoretical basis for treating wasterwater containing cyanic and nickelic compounds by forming the ferrites and highly pressured hydrolysis within one process.