Results
The results are showed as following:
（1）The size of NZVI and nanoscale Pd/Fe particles were less than 100nm;
（2）The nanoscale Pd/Fe particles exhibited high reactivity. It was observed that there was an obvious enhanced 2,4-DCP degradation reaction rate by using nanoscale Pd/Fe particles as catalysis and the Pd/Fe particles was prepared by solution phase reduction under ultrasonic irradiation;
Introduction
Some physical and chemical methods have also been used for the removal of CPs and their derivatives from wastewater. However the high cost and low efficiency of these processes limit their applicability.
Results
TEM images of NZVI particles
Results
TEM images of nanoscale Pd/Fe particles
Results
SEM images of NZVI particles
Results
SEM images of nanoscale Pd/Fe particles
Preparation of Ultra-fine NZVI Particle under
Ultrasound Irradiation and Reductive Dechlorination of
Chloro-organics by NVZI
Contents
Contents
Introduction Experimental Results
2,4-DCP was selected as a model compound due to its abundance in the contaminated groundwater.
2,4-Dichlorophenol We systematically discuss NZVI and nanoscale Pd/Fe bimetal reductive dechlorination of 2,4-orinated phenols (CPs) constitute an important class of pollutants because of their wide use in the production of wood preservers, pesticides and biocides. Due to their reactive nature, CPs are highly toxic, mutagenic and possibly carcinogenic. Furthermore, they are biorefractory and tend to accumulate in animal tissues. Once released into the environment, CPs will accumulate in the surrounding areas and pose a great health threat to humans and ecosystems over a long period of time, hence their fate in the environment is of great importance in waste treatment.
Experimental
How to get NZVI?
FeSO4·7H2O+2BH4－→Fe↓+2B（OH）3+7H2↑
How to get bimetallic Pd/Fe nanoparticles ?
PdCl62-+2Fe→2Fe2++Pd↓+6Cl-
Experimental
The reductive dechlorination of 2,4-DCP.
The batch experiments for 2,4-DCP dechlorination were performed in the same three-necked flask into which NZVI or Pd/Fe nanoparticles were added. 2,4-DCP stock solutions and a certain amount of deoxygenated deionized water were added into the flask containing freshly prepared NZVI or Pd/Fe nanoparticles. The reaction solution was stirred under nitrogen flow. Aliquots of samples were periodically collected with glass syringes and the reaction was quenched by passing through 0.45 μm membrane filters.
The use of NZVI and bimetallic Pd/Fe nanoparticles have shown to be an effective technology for the remediation of contaminated groundwaters.
Introduction