| 摘要 |
PROBLEM TO BE SOLVED: To safely and easily fix harmful heavy metals without generating an ammonia gas when treating heavy metal contaminants containing ammonia components and without substantially increasing the additive amount of a heavy metal fixing treatment agent. SOLUTION: In piperazine-N,N'-bis(carbodithionic acid) salt and/or piperazine-N-carbodithioic acid salt, especially the piperazine-N,N'-bis(carbodithionic acid) salt, decomposition by phosphoric acid and/or aluminium sulfate is small, and the heavy metals are fixed while suppressing ammonia gas generation without substantially increasing the using amount of the chelate. COPYRIGHT: (C)2007,JPO&INPIT |
