The present application relates to the field of remediation of heavy
metal pollution in sediments, and particularly relates to a fixing agent, a preparation method and application thereof. The fixing agent comprises
electron shuttles and dissimilatory
metal-reducing
bacteria. The fixing agent is used for fixing
heavy metals in water or remediation of heavy
metal contaminated sediments. The
heavy metals are selected from one or more of
cadmium and lead. The dissimilatory metal-reducing
bacteria used in the present application widely exist in river and lake sediments, and the sediments have strong adaptability and good heavy metal resistance. The
electron shuttles are used to strengthen the dissimilatory metal-reducing
bacteria to reduce and recrystallize the
cadmium after reducing the iron and
manganese oxides which exist in large quantities in the sediments. The sediments contain abundant
organic matter which can provide
carbon source for the dissimilatory metal-reducing bacteria, thereby avoiding the addition of
iron source,
manganese source and organic
carbon source, reducing the risk of secondary
pollution, and fully utilizing the abundant substances in the sediments to effectively fix the
heavy metals.