Syntheses and applications of nano-sized iron particles

Abstract

The present invention relates to syntheses of nano-sized iron particles formed by mixing a source of ferrous iron with a combination of reducing agent and base, and the particles formed therefrom.

1 . A process to produce nano-sized zerovalent iron particles, comprising the steps of:  
     a) forming a first aqueous solution comprising ferrous or ferric ions;  
     b) forming a second aqueous solution comprising a reducing agent and a base; and  
     c) mixing said first and second solutions together, thereby precipitating nano-sized zerovalent iron particles.  
   
   
       2 . The process of  claim 1 , wherein said first aqueous solution comprising ferrous ions is formed by dissolving ferrous chloride in deoxygenated water, and wherein the concentration of said ferrous ions is 1 g/l to 284 g/l.  
   
   
       3 . The process of  claim 1 , wherein said first aqueous solution comprising ferrous ions is formed by dissolving ferrous chloride in deoxygenated water, and wherein the concentration of said ferrous ions is 10 g/l to 100 g/l.  
   
   
       4 . The process of  claim 1 , wherein said reducing agent of said second solution is borohydride selected from NaBH4, KBH4, and LiBH4.  
   
   
       5 . The process of  claim 1 , wherein the concentration of said reducing agent is 0.1 g/l to 150 g/l.  
   
   
       6 . The process of  claim 1 , wherein said base is selected from NaOH, NH 4 OH, KOH or mixtures thereof.  
   
   
       7 . The process of  claim 5 , wherein the concentration of said base is 0.1 to 400 g/l.  
   
   
       8 . The process of  claim 1 , wherein the molar ratio of said reducing agent to said base is in the range of 0.1 to 10.  
   
   
       9 . The process of  claim 1 , wherein said mixing and particle formation are done in a batch mode.  
   
   
       10 . The process of  claim 1 , wherein said mixing and particle formation are done in a continuous process.  
   
   
       11 . Nano-sized zero valent iron particles formed by the process of  claim 1 .  
   
   
       12 . Nano-sized zerovalent iron particles formed by the process of  claim 1  wherein the iron particles exhibit a spherical morphology.  
   
   
       13 . Nano-sized zerovalent iron particles formed by the process of  claim 1  wherein the iron particles exhibit a needle-like morphology.  
   
   
       14 . Nano-sized zerovalent iron particles formed by the process of  claim 1  wherein the iron particles exhibit a flower-like morphology.