Physiochemical Characterization of Biochars from Six Feedstocks and Their Effects on the Sorption of Atrazine in an Organic Soil

Agronomy

Sanku Dattamudi¹  Saoli Chanda¹  Krishnaswamy Jayachandran¹  Shagufta Gaffar¹  AminRabiei Baboukani²  Chunlei Wang²  JeffreyM. Novak³  DonaldW. Watts³ 

[1] Department of Earth and Environment, Institute of Environment, Florida International University, Miami, FL 33199, USA;Department of Mechanical and Materials Engineering, Florida International University, Miami, FL 33174, USA;USDA-ARS-Coastal Palin Soil, Water and Plant Research Center, 2611 W Lucas St, Florence, SC 29501, USA;

关键词: biochar;    adsorption;    desorption;    atrazine;    hysteresis;   

DOI  :  10.3390/agronomy11040716

来源: DOAJ

【 摘 要 】

Application of biochars in agricultural soils has the potential to reduce groundwater contamination of atrazine, a widely used herbicide in the US, therefore sustaining environmental quality and reducing human health issues. This study was conducted to characterize biochars produced from six feedstocks and investigate their ability to remove and retain atrazine in an organic-rich soil. Australian pine (AP), Brazilian pepper (BP), coconut husk (CH), cypress (Cy), loblolly pine (L), and pecan shell (P) feedstocks were pyrolyzed at 350 °C and 500 °C. Adsorption and desorption behaviors of atrazine were explained using Freundlich isotherms. Higher pyrolysis temperature increased specific surface area (5 times), total pore volume (2.5 times), and aromaticity (1.4 times) of the biochars. CH feedstock produced the most effective biochars (CH350 and CH500), which adsorb 8–12% more atrazine than unamended soils. CH350 biochar performed the best (K_{d ads} = 13.80, K_OC = 153.63, K_{d des} = 16.98) and had significantly higher (p < 0.05) adsorption than unamended soil, possibly resulting from its highest cation exchange capacity (16.32 cmol kg⁻¹). The K_{d des} values for atrazine desorption were greater than the K_{d ads} for adsorption, indicating retention of a considerable amount of atrazine by the biochar-amended soils following desorption.

【 授权许可】

Unknown