Ceramic radiation shielding material and method of preparation

Abstract

A composition of matter and method of forming a radiation shielding member at ambient temperatures in which the composition of matter includes a phosphate bonded ceramic, a radiation shielding material dispersed in the phosphate bonded ceramic matrix.

1 . A composition of matter, comprising: 
 a phosphate based ceramic matrix; and    a radiation shielding material,    wherein the radiation shielding material is dispersed in the phosphate based ceramic matrix.    
   
   
       2 . The composition of matter of  claim 1 , wherein the radiation shielding material is selected from the group consisting of barite, barium sulfate, bismuth metal, zeolite, clinoptilotite, and celestite.  
   
   
       3 . The composition of matter of  claim 2 , wherein the zeolite is approximate by weight percentage 52.4% (fifty two point four percent) SiO 2  (silicon dioxide), 13.13% (thirteen point one three percent) Al 2 O 3  (alumina oxide), 8.94% (eight point nine four percent) Fe 2 O 3  (ferric oxide), 6.81% (six point eight one percent) CaO (calcium oxide), 2.64% (two point six four percent) Na 2 O (sodium oxide), 4.26% (four point two six percent) MgO (magnesium oxide).  
   
   
       4 . The composition of matter of  claim 1 , wherein barite by weight is approximately 89% (eighty nine percent) BaSO 4  (barium sulfate) and 5.8% (five point eight percent) silicates.  
   
   
       5 . The composition of matter of  claim 1 , wherein the phosphate based ceramic matrix is selected from the group consisting of MgHPO 4  magnesium hydrogen phosphate, Fe 3 (HPO 4 ) 2  (iron(II) phosphate), Fe 3 (HPO 4 ) 2 .8H 2 O (iron(II) phosphate octahydrate), FeHPO 4  (iron(II) phosphate), FeHPO 4 .2H 2 O (iron(III) phosphate dihydrate) AlPO 4  aluminum phosphate, AlPO 4 .1.5H 2 O (aluminum phosphate hydrate), CaHPO 4  (calcium hydrogen phosphate), CaHPO 4 .2H 2 O (calcium hydrogen phosphate dihydrate), BiPO 4  (bismuth phosphate), CePO 4  (cerium(III) phosphate), CePO 4 .2H 2 O (cerium(III) phosphate dihydrate), BaHPO 4  (barium hydrogen phosphate), and UPO 4  (depleted uranium (U-238) phosphate).  
   
   
       6 . The composition of matter of  claim 1 , wherein the phosphate based ceramic matrix is MgHPO 4 .3H 2 O ( magnesium hydrogen phosphate trihydrate).  
   
   
       7 . The composition of matter of  claim 1 , wherein the radiation shielding material is formed as at least one of aggregates or powder dispersed in the phosphate ceramic.  
   
   
       8 . The composition of matter of  claim 1 , wherein the phosphate ceramic matrix includes at least two different metal phosphates.  
   
   
       9 . The composition of matter of  claim 8 , wherein the at least two different metal phosphates are selected from the group consisting of magnesium hydrogen phosphate, iron(III) phosphate, aluminum phosphate, calcium hydrogen phosphate, bismuth phosphate, cerium(III) phosphate, and barium hydrogen phosphate.  
   
   
       10 . The composition of matter of  claim 1 , wherein the phosphate based ceramic matrix is of the formula:  
       MHPO 4 .xH 2 O  wherein M is a divalent cation selected from the group consisting of: Mg (magnesium), Ca (calcium), Fe (iron(II)), and Ba (barium); and    wherein x is at least one of 0 (zero), 2 (two), 3 (three), or 8 (eight).    
   
   
       11 . The composition of matter of  claim 1 , wherein the phosphate based ceramic matrix is of the formula:  
       MPO 4 .xH 2 O  wherein M is a trivalent cation selected from the group consisting of: Al (aluminum), Ce (cerium (III)), U 238  (depleated uranium) ; and Fe (iron(III)); and    wherein x is at least one of 0 (zero), 1.5 (one point five), or 2 (two).    
   
   
       12 . The composition of matter of  claim 1 , wherein the phosphate based ceramic matrix is of the formula:  
       MM′PO 4 .xH2O  wherein M is a divalent cation selected from the group consisting of: Ba (barium), and Mg (magnesium);    wherein M′ is a monovalent cation selected from the group consisting of: Li (lithium), Na (sodium), and K (potassium); and    wherein x is at least one of 0 (zero), 2 (two), 3 (three), or 6 (six).    
   
   
       13 . A radiation shielding composition of matter, comprising: 
 a cold fired phosphate based ceramic having, a cation constituent, exhibiting radiation shielding capability; and    a radiation shielding material selected from the group consisting of a powder, an aggregate, and a fiber,    wherein the radiation shielding material is dispersed in the cold fired phosphate based ceramic.    
   
   
       14 . The radiation shielding composition of matter of  claim 13 , wherein the cold fired phosphate based ceramic cures to hardness at less than 100° C. (one hundred degrees Celsius).  
   
   
       15 . The radiation shielding composition of matter of  claim 13 , wherein the cation is selected from the group consisting of aluminum, barium, bismuth, calcium, cerium, depleted uranium, iron, and magnesium.  
   
   
       16 . The radiation shielding composition of matter of  claim 13 , wherein the radiation shielding material is selected from the group consisting of barite, barium sulfate, bismuth metal, zeolite, clinoptilotite, and celestite.  
   
   
       17 . A composition of matter, consisting essentially of: 
 a cold fired phosphate based ceramic, having a cation constituent, exhibiting radiation shielding capability; and    a radiation shielding material dispersed in the cold fired phosphate based ceramic,    wherein the cation constituent is selected from the group consisting of aluminum, barium, bismuth, calcium, cerium, depleted uranium, iron, and magnesium.    
   
   
       18 . The composition of matter of  claim 17 , wherein the radiation shielding material is selected from the group consisting of barite, barium sulfate, bismuth metal, zeolite, clinoptilotite, plagioclase, pyroxene, olivine, and celestite.  
   
   
       19 . A method of constructing a radiation shielding member at ambient temperature, comprising: 
 mixing a metal oxide having a radiation shielding capability with a phosphate containing material;    incorporating a radiation shielding material into the metal oxide and phosphate containing material mix;    curing the incorporated radiation shielding material and metal oxide and phosphate containing material mix at ambient temperature.    
   
   
       20 . The method of constructing a radiation shielding member at temperature conditions of  claim 19 , wherein curing occurs at less than 100° C. (one hundred degrees Celsius).  
   
   
       21 . The method of constructing a radiation shielding member at ambient temperature of  claim 19 , wherein the phosphate containing material is phosphoric acid.