TY - JOUR
T1 - Phosphorus sorption capacity of biochars varies with biochar type and salinity level
AU - Dugdug, Abdelhafid Ahmed
AU - Chang, Scott X.
AU - Ok, Yong Sik
AU - Rajapaksha, Anushka Upamali
AU - Anyia, Anthony
N1 - Funding Information:
We thank Tim Anderson and Don Harfield for assistance with biochar production. We would like to thank Mr. Prem Pokharel for his help in revising the manuscript.
Funding Information:
Funding information The biochars used in this experiment were produced by Alberta Innovates-Technology Futures, Vegreville. Alberta Innovates-Technology Futures (now InnoTech Alberta) and the Natural Sciences and Engineering Research Council of Canada (NSERC) and Alberta Innovates-Technology Futures provided funding for this research
Publisher Copyright:
© 2018, Springer-Verlag GmbH Germany, part of Springer Nature.
PY - 2018/9/1
Y1 - 2018/9/1
N2 - Biochar is recognized as an effective material for recovering excess nutrients, including phosphorus (P), from aqueous solutions. Practically, that benefits the environment through reducing P losses from biochar-amended soils; however, how salinity influences P sorption by biochar is poorly understood and there has been no direct comparison on P sorption capacity between biochars derived from different feedstock types under non-saline and saline conditions. In this study, biochars derived from wheat straw, hardwood, and willow wood were used to compare P sorption at three levels of electrical conductivity (EC) (0, 4, and 8 dS m−1) to represent a wide range of salinity conditions. Phosphorus sorption by wheat straw and hardwood biochars increased as aqueous solution P concentration increased, with willow wood biochar exhibiting an opposite trend for P sorption. However, the pattern for P sorption became the same as the other biochars after the willow wood biochar was de-ashed with 1 M HCl and 0.05 M HF. Willow wood biochar had the highest P sorption (1.93 mg g−1) followed by hardwood (1.20 mg g−1) and wheat straw biochars (1.06 mg g−1) in a 25 mg L−1 P solution. Although the pH in the equilibrium solution was higher with willow wood biochar (~ 9.5) than with the other two biochars (~ 6.5), solution pH had no or minor effects on P sorption by willow wood biochar. The high sorption rate of P by willow wood biochar could be attributed to the higher concentrations of salt and other elements (i.e., Ca and Mg) in the biochar in comparison to that in wheat straw and hardwood biochars; the EC values were 2.27, 0.53, and 0.27 dS m−1 for willow wood, wheat straw, and hardwood biochars, respectively. A portion of P desorbed from the willow wood biochar; and that desorption increased with the decreasing P concentration in the aqueous solution. Salinity in the aqueous solution influenced P sorption by hardwood and willow wood but not by wheat straw biochar. We conclude that the P sorption capacity of the studied biochars is dependent on the concentration of the soluble element in the biochar, which is dependent on the biochar type, as well as the salinity level in the aqueous solution.
AB - Biochar is recognized as an effective material for recovering excess nutrients, including phosphorus (P), from aqueous solutions. Practically, that benefits the environment through reducing P losses from biochar-amended soils; however, how salinity influences P sorption by biochar is poorly understood and there has been no direct comparison on P sorption capacity between biochars derived from different feedstock types under non-saline and saline conditions. In this study, biochars derived from wheat straw, hardwood, and willow wood were used to compare P sorption at three levels of electrical conductivity (EC) (0, 4, and 8 dS m−1) to represent a wide range of salinity conditions. Phosphorus sorption by wheat straw and hardwood biochars increased as aqueous solution P concentration increased, with willow wood biochar exhibiting an opposite trend for P sorption. However, the pattern for P sorption became the same as the other biochars after the willow wood biochar was de-ashed with 1 M HCl and 0.05 M HF. Willow wood biochar had the highest P sorption (1.93 mg g−1) followed by hardwood (1.20 mg g−1) and wheat straw biochars (1.06 mg g−1) in a 25 mg L−1 P solution. Although the pH in the equilibrium solution was higher with willow wood biochar (~ 9.5) than with the other two biochars (~ 6.5), solution pH had no or minor effects on P sorption by willow wood biochar. The high sorption rate of P by willow wood biochar could be attributed to the higher concentrations of salt and other elements (i.e., Ca and Mg) in the biochar in comparison to that in wheat straw and hardwood biochars; the EC values were 2.27, 0.53, and 0.27 dS m−1 for willow wood, wheat straw, and hardwood biochars, respectively. A portion of P desorbed from the willow wood biochar; and that desorption increased with the decreasing P concentration in the aqueous solution. Salinity in the aqueous solution influenced P sorption by hardwood and willow wood but not by wheat straw biochar. We conclude that the P sorption capacity of the studied biochars is dependent on the concentration of the soluble element in the biochar, which is dependent on the biochar type, as well as the salinity level in the aqueous solution.
KW - Biochar
KW - Equilibrium solution
KW - Feedstock type
KW - Phosphorus sorption
KW - Salt stress
KW - Wheat straw
KW - Wood
UR - http://www.scopus.com/inward/record.url?scp=85041925570&partnerID=8YFLogxK
U2 - 10.1007/s11356-018-1368-9
DO - 10.1007/s11356-018-1368-9
M3 - Article
C2 - 29429110
AN - SCOPUS:85041925570
VL - 25
SP - 25799
EP - 25812
JO - Environmental Science and Pollution Research
JF - Environmental Science and Pollution Research
SN - 0944-1344
IS - 26
ER -