Metal removal efficiency of novel LD-slag-incorporated ceramic membrane from steel plant wastewater

ABSTRACT

This work focuses on the preparation and characterisation of novel LD-slag (by product of Linz-Donawitz process in Steel Industry)-based ceramic membrane. LD-slag powder along with other pore forming and binding agents such as boric acid, sodium metasilicate, sodium carbonate and alumina, were blended and casted into membrane by the simple paste casting method. The prepared membrane sintered at 700 ºC was found to have enhanced temperature resistivity, mechanical strength and excellent separation efficiency. The prepared ceramic membrane had an average pore diameter of 0.73–1.77 µm and porosity ranging from 31.13 to 55.5%. The prepared membrane was further used for the microfiltration of electro-coagulated wastewater obtained from Tata Steel plant, India to retain the flocks and metal ions obtained after electrocoagulation process. A novel metal ion removal mechanism was proposed based on electrostatic attraction-repulsion phenomenon between the membrane surface and pollutants.

KEYWORDS:

• LD-slag
• ceramic membrane
• microfiltation
• metal removal

Highlights

1. Preparation of novel ceramic membrane utilising LD-slag, by-product from Tata Steel Industry.

2. The prepared ceramic membrane had an average pore diameter of 0.73 - 1.77 µm at 700ºC.

3. Metal removal efficiency for Iron and Manganese through microfiltration reached 100%.

4. Novel metal removal mechanism was proposed based on surface electrostatic attraction-repulsion phenomenon.

Acknowledgments

This work was supported by a grant from TATA STEEL LIMITED, Jamshedpur. Any opinions, findings and conclusions expressed in this paper are those of the authors and do not necessarily reflect the views of TATA STEEL LIMITED, Jamshedpur.

Disclosure Statement

No potential conflict of interest was reported by the author(s).