Removing Gaseous NH 3 Using Biochar as an Adsorbent

Kyoung S. Ro, Isabel M. Lima, Guidqopuram B. Reddy, Michael A. Jackson and Bin Gao
Additional contact information
Kyoung S. Ro: USDA-ARS Coastal Plains Soil, Water and Plant Research Center, Florence, SC 29501, USA
Isabel M. Lima: USDA-ARS Southern Regional Research Center, New Orleans, LA 70124, USA
Guidqopuram B. Reddy: Department of Natural Resources, North Carolina Agricultural and Technical State University, Greensboro, NC 27411, USA
Michael A. Jackson: USDA-ARS National Center for Agricultural Utilization Research, Peoria, IL 61604, USA
Bin Gao: Department of Agricultural and Biological Engineering, University of Florida, Gainesville, FL 32611, USA

Agriculture, 2015, vol. 5, issue 4, 1-12

Abstract: Ammonia is a major fugitive gas emitted from livestock operations and fertilization production. This study tested the potential of various biochars in removing gaseous ammonia via adsorption processes. Gaseous ammonia adsorption capacities of various biochars made from wood shaving and chicken litter with different thermal conditions and activation techniques were determined using laboratory adsorption column tests. Ammonia adsorption capacities of non-activated biochars ranged from 0.15 to 5.09 mg·N/g, which were comparable to that of other commercial activated carbon and natural zeolite. There were no significant differences in ammonia adsorption capacities of steam activated and non-activated biochars even if the surface areas of the steam activated biochars were about two orders of magnitude greater than that of non-activated biochars. In contrast, phosphoric acid activation greatly increased the biochar ammonia adsorption capacity. This suggests that the surface area of biochar did not readily control gaseous NH 3 adsorption. Ammonia adsorption capacities were more or less linearly increased with acidic oxygen surface groups of non-activated and steam-activated biochars. Phosphoric acid bound to the acid activated biochars is suspected to contribute to the exceptionally high ammonia adsorption capacity. The sorption capacities of virgin and water-washed biochar samples were not different, suggesting the potential to regenerate spent biochar simply with water instead of energy- and capital-intensive steam. The results of this study suggest that non-activated biochars can successfully replace commercial activated carbon in removing gaseous ammonia and the removal efficiency will greatly increase if the biochars are activated with phosphoric acid.

Keywords: gaseous ammonia; biochar; adsorption; activation; regeneration (search for similar items in EconPapers)
JEL-codes: Q1 Q10 Q11 Q12 Q13 Q14 Q15 Q16 Q17 Q18 (search for similar items in EconPapers)
Date: 2015
References: View references in EconPapers View complete reference list from CitEc
Citations: View citations in EconPapers (3)

Downloads: (external link)
https://www.mdpi.com/2077-0472/5/4/991/pdf (application/pdf)
https://www.mdpi.com/2077-0472/5/4/991/ (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:jagris:v:5:y:2015:i:4:p:991-1002:d:56616

Access Statistics for this article

Agriculture is currently edited by Ms. Leda Xuan

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