Catalytic hydrodechlorination of monochloroacetic acid in wastewater using Ni-Fe bimetal prepared by ball milling

Abstract

Monochloroacetic acid (MCA) is a chemically stable and biologically toxic pollutant. It is often generated during the production of the pesticide dimethoate. Conventional wastewater treatment processes have difficulty degrading it. In this work, the dechlorination effects of Ni-Fe bimetal prepared using ball milling (BM) technology for the high concentrations of MCA in wastewater were examined. The MCA in aqueous solution was found to be degraded efficiently by the Ni-Fe bimetal. However, S-(methoxycarbonyl) methyl O, O-dimethyl phosphorodithioate (SMOPD) in wastewater, a by-product of the dimethoate production process, significantly inhibited the reductive dechlorination activity of Ni-Fe bimetal. Increasing the reaction temperature in the MCA wastewater enhanced the reduction activity of the Ni-Fe bimetal effectively. Oxygen was found to be unfavorable to dechlorination. Sealing the reaction to prevent oxidation was found to render the degradation process more efficient. The process retained over 88% efficiency after 10 treatment cycles with 50 g/L of Ni-Fe bimetal under field conditions.

One-pot synthesis of highly active Ni/Fe nano-bimetal by simultaneous ball milling and in situ chemical deposition

“…S3, † with the increase of milling time, the diffraction peaks were shied to the low-angle direction and the peak widths tended to get broader due to the formation of grain interface structural defects. 31,32 The strains and defects of milled bimetal can also be observed by the change in magnetic properties (Fig. 2b).…”

“…29 Recent studies suggested that Ni-Fe bimetals showed superior degradation activity prepared by ball milling (BM). 21,[29][30][31][32] Whereas, in BM process Ni can be homogeneously distributed over the Fe surface instead of the surface coverage of metals occurred in the CSD process. 33 But bimetals prepared by BM usually have larger grain size and low compactness of two metals, which is unfavorable for dechlorination reaction.…”

A new approach to 4-chlorophenol dechlorination on monometallic copper compared to its Cu/Fe bimetallic system

“…Nickel was reported to improve the reduction rate interacting copper [13]. The Ball-milling (BM) technique is an unique bimetal preparation method to improve the dechlorination activity of bimetals as previously reported [25]. Therefore BM bimetals of copper might have improved dechlorination activity compared to monometallic Cu 0 .…”

Enhanced hydrodechlorination of 4-chlorophenol by Cu/Fe bimetallic system via ball-milling

“…New methods for the preparation of Cu/Fe bimetallic systems with stable and higher dechlorination activity are needed. In recent years, ball-milling (BM) has been successfully used to prepare Ni-Fe bimetallic system [19,20]. BM is effective in preparing the bimetallic system with homogenously distribution and controllable mass fraction ratios.…”

“…BM is effective in preparing the bimetallic system with homogenously distribution and controllable mass fraction ratios. It is effective in preparing bimetallic systems with good performance for HDC of 4-chlorophenol (4-CP) [20] and monochloroacetic acid [19]. To date, only bimetallic systems containing precious metals such as Pd-Mg [21], and Ni-Fe [19,20] bimetallic system were prepared by BM for HDC.…”