Study on the ammonium adsorption capacity of aluminosilicate-based geopolymer for livestock wastewater treatment at Giang Son Commune, Gia Binh District, Bac Ninh Province

Abstract

Effective wastewater treatment before discharging into the surrounding environment is one of the significant stages in production activities for economic development and environmental protection. This paper presented the evaluation and comparison of the ammonium adsorption capacity of geopolymers modified from aluminosilicate materials including fly ash, laterite, and bentonite for livestock wastewater treatment at Giang Son Commune, Gia Binh District, Bac Ninh Province. The obtained results showed that the raw fly ash, laterite, and bentonite possessed low adsorption capacity and efficiency with values of 0.19 mg/g, 8.53%; 0.28 mg/g, 10.54%; and 0.175 mg/g, 7.95%, respectively. After modification with NaOH and Na2SiO3 solutions, the NH4+ adsorption efficiency of these materials increased approximately 6.4 times. Among them, the laterite-based geopolymer showed the highest ammonium adsorption capacity and efficiency of 1.26 mg/g and 54.3%, respectively. In addition, ammonium concentration in the livestock wastewater after biogas digester treatment was 120241 mg/L with an average value 1.26 times higher than the limited value in the QCVN 62-MT:2016/BTNMT. The geopolymer from laterite removed NH4+ in the livestock wastewater after biogas to the limited value in QCVN 62-MT:2016/BTNMT. Further studies with different experimental conditions should be conducted to determine the optimal conditions for the ammonium adsorption capacity of these geopolymer materials.