Chemical functionalization of drinking water treatment residuals with calcium silicate hydrate to treat metal-enriched waters

 

TitleChemical functionalization of drinking water treatment residuals with calcium silicate hydrate to treat metal-enriched waters
AuthorAlejandro Briso, Ana Turri, Mauricio Montecinos, María Molinos, Pablo Pasten
Line(s)

Recursos Críticos

Year of Publication2023
Journal TitleJournal of Water Process Engineering
Keywords
Adsorption; Drinking water treatment plants; Environmental pollution; Reuse; Sludge; Circular economy
AbstractDrinking water treatment residuals (DWTRs) provide an opportunity to further embrace circular economy in the urban water cycle. DWTRs surface properties can be improved by chemical functionalization to enhance the pollutant removal performance. Fe/Al-DWTRs were functionalized with nanostructured calcium silicate (nanoCSH) to remove Cu(II) and As(V) from rivers, simulating an accidental acid spill. Model raw DWTRs were generated using raw water. DWTRs were physicochemically characterized by a multi-technique approach (SEM-EDS, FT-IR, BET, XRD). Sorption experiments were performed using Cu(II) and As(V) by varying the initial pH and DWTRs doses. Compared with raw DWTRs, NanoCSH_DWTRs demonstrated a higher removal efficiency in acidic settings, faster removal rates, and higher effectiveness at lower dosages. Kinetic and equilibrium sorption experiments were performed. Experiments simulating accidental Cu and As pollution from acid drainage revealed that NanoCSH_DWTRs had a higher collective removal of As(V) when Cu(II) was present, most likely due to the synergistic relationship formed by the tertiary metal-surface complexes. An application approach was implemented using theoretical case studies. NanoCSH_DWTRs reduced the dose required to treat metal(loid)-enriched water compared to raw DWTRs. NanoCSH_DWTRs would provide an alternative as a first line of defense against the accidental release of acidic drainage.
Doihttps://doi.org/10.1016/j.jwpe.2023.103884
Corresponding Author
María Molinos, mmolinos@uc.cl