Ammonium Sorption from Landfill Leachates Using Natural and Modified Zeolites: Pre-Tests for a Novel Application of the Ion Exchanger Loop Stripping Process

Vollprecht, Frühauf, Stocker, Ellersdorfer
2019 Minerals  
Ammonium (NH4+) is a main constituent of landfill leachates (50–2200 mg L−1) which has to be removed prior to indirect (<200 mg L−1) or direct discharge (<10 mg L−1) during landfill operation and aftercare, i.e., for more than 100 years after the end of waste disposal. In this study, lab‐scale experiments regarding the sorption of NH4+ from landfill leachates using natural and modified clinoptilolite (Ca0.5,Na,K)6(Al6Si30)O72·20H2O) were conducted to assess the applicability of the innovative
more » ... of the innovative ion exchanger loop stripping (ILS) process for ammonium recovery. Samples of 20 g clinoptilolite after different pre-treatments (Ca loading, Na loading, natural loading) were shaken with 500 mL of each leachate from ten Austrian landfills (75 mg L−1 < c(NH4+) < 2805 mg L−1; 7.7 < pH < 8.7) for 24 h. Between 13% and 61% of the dissolved NH4+ was adsorbed to the clinoptilolite, which remained stable during the experiment. In summary, our study indicates that the ILS process is highly promising with respect to NH4+ recovery from landfill leachates, but further research is needed to reach threshold values for direct discharge.
doi:10.3390/min9080471 fatcat:spx5c2ux2jccfjuqj22rf3rd2m