Recovery TiO 2 and sodium titanate nanowires as Cd(II) adsorbent from waste V 2 O 5 -WO 3 /TiO 2 selective catalytic reduction catalysts by Na 2 CO 3 -NaCl-KCl molten salt roasting method

•Leaching rate of W and V were 99.3% and 98.4% by Na2CO3-NaCl-KCl molten salt roasting method.•The consumption of Na2CO3 was 12% compared conventional soda roasting method.•TiO2/STNWs were prepared from waste SCR catalyst and used as Cd(II) adsorbent.•The maximal adsorption capacity of TiO2/STNWs is 146.5 mg/g.