Immobilization of lead in shooting range soil using biochar from spent mushroomsubstrateImmobilization of lead in shooting range soil using biochar from spent mushroomsubstrate

Abstract

Spent mushroom substrate (SMS) was pyrolyzed at 450°C for 2 hours and characterized using elemental analyzer and Boehm titration. Shooting range soil was incubated with 2.5% w/w and 5.0% w/w of SMSB for four weeks and the soil were characterized on the elemental
composition, pH, electric conductivity (EC) and cation exchange capacity (CEC). The
mobility of Pb in the incubated soil were studied using a modified selective sequential
extraction (SSE) scheme. Total Pb in shooting range soil is 29385.5 mg/kg. The texture of
shooting range soil is loamy sand with an average soil pH of 4.69, EC value 0.17 mS/mand
CEC value 6.0 mEq/100g. After treatment with SMSB, the soil pH and CEC were increased
and the concentration of exchangeable Pb decreased. Conclusively, this study found that there
is potential in using SMSB for remediating Pb contamination in the shooting range soil.

Keywords: Spent mushroom compost; charcoal; black carbon; immobilization