Rapid Adsorption of Ammonium on Coffee Husk and Chicken Manure-Derived Biochars: Mechanisms Unveiled by Chemical Speciation, Physical, and Spectroscopic Approaches

Everton Geraldo de Morais, Carlos Alberto Silva, Suduan Gao, Leônidas Carrijo Azevedo Melo, Pedro Antônio Namorato Benevenute, Bruno Cocco Lago, Jéssica Cristina Teodoro and Luiz Roberto Guimarães Guilherme ()
Additional contact information
Everton Geraldo de Morais: Department of Soil Science, Federal University of Lavras, University Campus, P.O. Box 3037, Lavras 37203-202, MG, Brazil
Carlos Alberto Silva: Department of Soil Science, Federal University of Lavras, University Campus, P.O. Box 3037, Lavras 37203-202, MG, Brazil
Suduan Gao: United States Department of Agriculture (USDA)—Agricultural Research Service, San Joaquin Valley Agricultural Sciences Center, 9611 South Riverbend Avenue, Parlier, CA 93648-9757, USA
Leônidas Carrijo Azevedo Melo: Department of Soil Science, Federal University of Lavras, University Campus, P.O. Box 3037, Lavras 37203-202, MG, Brazil
Pedro Antônio Namorato Benevenute: Department of Soil Science, Federal University of Lavras, University Campus, P.O. Box 3037, Lavras 37203-202, MG, Brazil
Bruno Cocco Lago: Department of Soil Science, Federal University of Lavras, University Campus, P.O. Box 3037, Lavras 37203-202, MG, Brazil
Jéssica Cristina Teodoro: Department of Soil Science, Federal University of Lavras, University Campus, P.O. Box 3037, Lavras 37203-202, MG, Brazil
Luiz Roberto Guimarães Guilherme: Department of Soil Science, Federal University of Lavras, University Campus, P.O. Box 3037, Lavras 37203-202, MG, Brazil

Sustainability, 2025, vol. 17, issue 4, 1-16

Abstract: Biochars have emerged as a sustainable technology for converting waste into high-value, stable carbon products. Depending on its properties, biochar can retain various elements, including nitrogen (N) as ammonium (N-NH 4 + ). This study aimed to evaluate the rapid retention of N-NH 4 + in biochars produced from coffee husk (CH) and chicken manure (CM) at different pyrolysis temperatures (PTs) (300 °C, 400 °C, and 900 °C) and investigate the mechanisms involved. A rapid N-NH 4 + adsorption experiment was conducted, in which an NH 4 Cl solution was passed through the biochars. The following analyses were performed: cation exchange capacity (CEC), surface area, pore volume and size, total N content, N retention, infrared analysis (ATR-FTIR), and leachate solution analysis, followed by chemical speciation using Visual MINTEQ software. The results indicated that different mechanisms were involved in rapid N-NH 4 + retention. In CH-derived biochars produced at 300 °C, N-NH 4 + retention occurred primarily through electrostatic interactions with negative charges (CEC), as confirmed by ATR-FTIR analysis. In CM-derived biochars produced at 400 °C, N-NH 4 + retention was mainly through the formation of struvite (NH 4 MgPO 4 ·6H 2 O), as confirmed by chemical speciation of leachate solution in Visual MINTEQ. In CH-derived biochars produced at 900 °C, N-NH 4 + ions were trapped in the pores of the charred matrix due to the increased biochar surface area, pore volume, and decreased pore size. The biochars studied proved effective in retaining N-NH 4 + through different mechanisms, suggesting that biochars can enhance rapid N retention and reduce N leaching, potentially serving as a source of N for crops.

Keywords: nitrogen retention; pyrolysis conditions; chemical speciation (search for similar items in EconPapers)
JEL-codes: O13 Q Q0 Q2 Q3 Q5 Q56 (search for similar items in EconPapers)
Date: 2025
References: View references in EconPapers View complete reference list from CitEc
Citations:

Downloads: (external link)
https://www.mdpi.com/2071-1050/17/4/1616/pdf (application/pdf)
https://www.mdpi.com/2071-1050/17/4/1616/ (text/html)

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:gam:jsusta:v:17:y:2025:i:4:p:1616-:d:1592055

Access Statistics for this article

Sustainability is currently edited by Ms. Alexandra Wu

More articles in Sustainability from MDPI
Bibliographic data for series maintained by MDPI Indexing Manager ().