Development of the Technology for Processing Plant Breeding By-Products to Obtain Biosorbent

Abstract

This study focuses on the potential transforming sunflower husk wastes into innovative green products to be used for the recultivation of contaminated soils. This transformation makes it possible to utilize the large quantity plant breeding by-products to obtain a highly porous biosorbent. Optimal conditions for the preparation of bisorbents can be determined based on measurements of their specific surface and porosity. It is shown that structural characteristics of sorbent depend on conditions of the pyrolysis of primary raw material. Optimal conditions for obtaining biosorbent with a specified proportion of mesoand micropores and high specific surface are performed under three-stage pyrolysis as given by following conditions: sample holding time of 10-30 min, final temperature 700°С, and heating rate 15°С/min. A 3-month incubation study was conducted to investigate its performance in stabilization of copper contamination in Fluvisol. The sequential extraction procedure showed that the 1% sunflower husks biosorbent treatment reduced the mobile pool (exchange and carbon-bonded fractions) of Cu from 8 to 4%, respectively, compared to the contaminated soil. Cu is found to be tightly bonded owing to the increase of the residual and organic matter-bonded metal fractions. Owing to its adsorptive properties, biosorbent amendment of coppercontaminated soils appears as a promising approach to reduce the pollutant mobility and bioavailability.