Phosphorus adsorption using chemical and metal chloride activated biochars: Isotherms, kinetics and mechanism study
Bijoy Biswas,
Tawsif Rahman,
Manish Sakhakarmy,
Hossein Jahromi,
Mohamed Eisa,
Jonas Baltrusaitis,
Jasmeet Lamba,
Allen Torbert,
Sushil Adhikari
Affiliations
Bijoy Biswas
Biosystems Engineering Department, 200 Corley Building, Auburn University, Auburn, AL 36849, USA; Center for Bioenergy and Bioproducts, 519 Devall Drive, Auburn University, Auburn, AL 36849, USA
Tawsif Rahman
Biosystems Engineering Department, 200 Corley Building, Auburn University, Auburn, AL 36849, USA
Manish Sakhakarmy
Biosystems Engineering Department, 200 Corley Building, Auburn University, Auburn, AL 36849, USA
Hossein Jahromi
Biosystems Engineering Department, 200 Corley Building, Auburn University, Auburn, AL 36849, USA; Center for Bioenergy and Bioproducts, 519 Devall Drive, Auburn University, Auburn, AL 36849, USA
Mohamed Eisa
Department of Chemical and Biomolecular Engineering, Lehigh University, USA
Jonas Baltrusaitis
Department of Chemical and Biomolecular Engineering, Lehigh University, USA
Jasmeet Lamba
Biosystems Engineering Department, 200 Corley Building, Auburn University, Auburn, AL 36849, USA
Allen Torbert
National Soil Dynamics Laboratory, United States Department of Agriculture-Agriculture Research Service, Auburn, AL 36832, USA
Sushil Adhikari
Biosystems Engineering Department, 200 Corley Building, Auburn University, Auburn, AL 36849, USA; Center for Bioenergy and Bioproducts, 519 Devall Drive, Auburn University, Auburn, AL 36849, USA; Corresponding author. Center for Bioenergy and Bioproducts, 519 Devall Drive, Auburn University, Auburn, AL 36849, USA.
Efficient treatment of nutrient-rich wastewater is of paramount importance for protecting the ecosystem. In this work, an efficient, abundant, and eco-friendly adsorbent was derived from biochar and employed for phosphorus (P) adsorption. The key factors influencing the P removal efficiency of the activated biochar, including P concentration, pH, dosage, temperature, adsorption time, and influence of co-existing ion type, were investigated. Maximum P adsorption percentage (100%) was obtained with 10 mg/L and zinc chloride activated biochar (BC–Zn) compared to the other activated biochars. Results show that by increasing the P concentration from 5 to 200 mg/L, the phosphorus adsorption capacity increases from 0.13 to 10.4 mg/g biochar. Isotherms and kinetic studies further show that the P adsorption follows the Langmuir and quasi-second-order kinetic models. The mechanistic investigation demonstrated that P adsorption occurred by precipitation reaction. Furthermore, P desorption has been studied at different time intervals to understand the P release rate after adsorption.
