Investigation of the possibility of silver recovery in the ethylene oxide catalyst for reuse in catalyst preparation

Due to The environmental problem of burying spent catalysts , considerations of sustainable development , Economic value and high usage of the noble metals , Recovery ofthese precious metals from spent catalysts , have attracted a great deal of attention and importance in recent years[1] . In this Research , recovery of the precious metal of silver from Ethylene oxide spent catalyst(Ag /Al2o3 , has been investigated .in the recovery process, silver , in the from of Nitrate solution has been recoverd by Nitric Acid as the extractant solvent , and after separating it from the solution and purifying it with recrystalyzation process , it has been converted to silver oxid (I) by Hydroxide Sodium[2] .Experimental results as well as the measurement of the extracted silver , determined using Atomic Absortion and XRF method , show the recovered silver with a purity of 99.99% .