Effect of water treatment residuals and cement kiln dust on COD adsorption and heavy metals from textile wastewater

2020 ◽  
Vol 205 ◽  
pp. 336-342
Author(s):  
Esawy Mahmoud ◽  
Wafaa Hammad ◽  
Othman Hakami
ACS Omega ◽  
2020 ◽  
Vol 5 (38) ◽  
pp. 24351-24355
Author(s):  
Ye Hwan Lee ◽  
Heejae Yang ◽  
Sang Moon Lee ◽  
Sung Su Kim

2020 ◽  
Vol 8 (2) ◽  
pp. 161-170
Author(s):  
Anwar Ahmad ◽  
Sultan Al Ghadeer ◽  
Talal K. Al-Hosni

2014 ◽  
Vol 70 (6) ◽  
pp. 1011-1018 ◽  
Author(s):  
Mohamed El Zayat ◽  
Sherien Elagroudy ◽  
Salah El Haggar

Ion exchange, reverse osmosis, and chemical precipitation have been investigated extensively for heavy metal uptake. However, they are deemed too expensive to meet stringent effluent characteristics. In this study, cement kiln dust (CKD) was examined for the removal of target heavy metals. Adsorption studies in completely mixed batch reactors were used to generate equilibrium pH adsorption edges. Studies showed the ability of CKD to remove the target heavy metals in a pH range below that of precipitation after an equilibrium reaction time of 24 h. A surface titration experiment indicated negative surface charge of the CKD at pH below 10, meaning that electrostatic attraction of the divalent metals can occur below the pH required for precipitation. However, surface complexation was also important due to the substantive metal removal. Accordingly, a surface complexation model approach that utilizes an electrostatic term in the double-layer description was used to estimate equilibrium constants for the protolysis interactions of the CKD surface as well as equilibria between background ions and the sorbent surface. It was concluded that the removal strength of adsorption is in the order: Pb > Cu > Cd. The experiments were also supported by Fourier transform infrared spectroscopy (FTIR).


Sign in / Sign up

Export Citation Format

Share Document