Patent ID: 8034158

Claim:
A method of manufacturing an Fe/Ni-containing material from an Fe/Ni-containing liquid waste, comprising: preparing an Fe/Ni/SO 4 -containing liquid waste in which a value of [Fe(+3) ion concentration]/[Ni ion concentration +Fe(+2) ion concentration] is 1 or less; removing SO 4 from the liquid waste by adding an SO 4 neutralizing agent to the liquid waste so that pH of the liquid waste is maintained to pH 0.5 to 4.5; precipitating Fe and Ni in the form of hydroxide [(Ni,Fe)(OH) 2 ] by adding NaOH to the SO 4 -free solution; washing the precipitate with water; and manufacturing an Ni/Fe-containing material by filtering and drying the washed precipitate.