Sorption and Juglans regia-derived activated carbon-mediated removal of aniline-based herbicide Alachlor from contaminated soils

• Published in: Environmental earth sciences 2018-06, Vol.77 (12), p.1-10, Article 437
• Main Author: Ahmad, Khuram Shahzad
• Format: Article
• Language: English
• Subjects: Activated carbon; Adsorption; Alachlor; Aniline; Biogeosciences; Correlation analysis; Decontamination; Desert environments; Earth and Environmental Science; Earth Sciences; Environmental Science and Engineering; Geochemistry; Geology; Green remediation; Herbicides; Hydrology/Water Resources; Isotherms; Juglans regia; Organic matter; Original Article; Pesticides; Removal; Shells; Soil; Soil chemistry; Soil contamination; Soil investigations; Soil pH; Soil remediation; Sorption; Statistical analysis; Statistical methods; Terrestrial Pollution; Variance analysis; Walnuts
• ISSN: 1866-6280; 1866-6299
• DOI: 10.1007/s12665-018-7633-x

Alachlor interaction with soil has been evaluated by batch equilibrium method on nine soils, geographically distant, from hilly to desert areas. Different soil samples have been investigated for sorption and removal mechanism of Alachlor. Linear and Freundlich soil–pesticide sorption isotherms were used to study the adsorption phenomena. Distribution coefficient ( K d ) shifted extraordinarily from 94.9 to 6.15 µg mL −1 . Statistical analysis showed a negative correlation between soil pH and K d ( R 2  = − 0.70) and a positive relationship with organic matter content ( R 2  = 0.80). The adsorption results gave a C-type isotherm. The results were additionally investigated by univariate ANOVA and their accuracy was checked through residual plots. Activated carbon prepared from walnut shells ( Juglans regia ) was utilized for green remediation of Alachlor-contaminated soils, proved to be a cost-effective absorbent. The influence of two parameters including pesticide concentration and contact time for the abatement of Alachlor were investigated. Most prominent removal in 5 ppm Alachlor concentration was 84% while in 7.5 ppm most astounding removal was 72% from soils. The utilization of Juglans regia shells for decontamination of soils makes this technique environmental friendly, economical and easily applicable.