Adsorptive capacity of spray-dried pH-treated bentonite and kaolin powders for ammonium removal

• Published in: Advanced Powder Technology
• Main Author: Zaini N.S.M.; Lenggoro I.W.; Naim M.N.; Yoshida N.; Man H.C.; Bakar N.F.A.; Puasa S.W.
• Format: Article
• Language: English
• Published: Elsevier B.V. 2021
• Online Access: https://www.scopus.com/inward/record.uri?eid=2-s2.0-85104315158&doi=10.1016%2fj.apt.2021.02.036&partnerID=40&md5=9ac7dc6271e3b28d19dd202a5830471c
• ISSN: 09218831
• DOI: 10.1016/j.apt.2021.02.036

The effectiveness of ammonium (NH4+) adsorption was investigated, using spray-dried, pH-treated bentonite, and kaolin as adsorbents. Each powder's adsorption capacity towards NH4+ was examined after up to 120 min of sample exposure, and results were compared. The zeta potential values for bentonite samples were between −1.1 and −19.4 mV, while for kaolin samples, they were between −35.7 and −40.9 mV (pH range examined was 2–10). The adsorption isotherm for bentonite showed a fit with the Langmuir model. The pH 10-treated bentonite and as-received bentonite (dispersed as pH 10 in distilled water) showed the highest adsorption capacity towards NH4+. Meanwhile, for kaolin, the adsorption capacity was low and observed only at low NH4+ concentration (100 mg/L and 200 mg/L), with pH 10-treated kaolin showed the highest adsorption capacity. © 2021 Society of Powder Technology Japan