Comparison of Fenitrothion and Trifluralin Adsorption on Organo-Zeolites and Activated Carbon. Part I: Pesticides Adsorption Isotherms on Adsorbents

Abstract

In the past decades, natural zeolites have found a important role in adsorption applications due to their local availability and low cost preparation. In this study, surface of natural zeolite sample was modified by using cationic surfactants in order to investigate its adsorption capacity to remove pesticides from wastewater. Data obtained from adsorption studies on organo-zeolites were compared with data obtained from those on activated carbon. To determine the adsorption process and properties, the effects of various operating parameters, pH of the solution (3-11), initial concentration of pesticides (5-20 mg Á L À1 ), contact time (10-350 min), and temperature (25-55 C) were investigated in a batch adsorption technique. According to results, the adsorbed amount of fenitrothion on three different adsorbents decreased whereas those of trifluralin on the adsorbents increased with increasing temperature. Langmuir and Freundlich adsorption models were applied to experimental equilibrium data of pesticide adsorption depending on temperature. The data obtained from adsorption isotherms for organo-zeolites and activated carbon were well fitted to the Freundlich model at all temperatures.

Sorption/Desorption and Kinetics of Atrazine, Chlorfenvinphos, Endosulfan Sulfate and Trifluralin on Agro-Industrial and Composted Organic Wastes

“…The authors of [61] studied the sorption of atrazine and trifluralin on soils, obtaining K fa values from 0.9 to 13.0 L Kg −1 for atrazine and from 3.9 to 8.8 L Kg −1 for trifluralin. Values of trifluralin's K fa in soil varied from 20.1 to 743 L Kg −1 [48,50], and from 290 and 1590 for zeolites and 3240 for activated carbon [62]. In [63], k d values between 106 and 294 were obtained for the adsorption of trifluralin in five agricultural soils of the UK and K oc values of 63 ± 10. k d values of 1.28, 1.6, 57.6, 332 to 807, and 87 to 1010 L Kg −1 were obtained for atrazine sorption on ultisol [64], soil amended with sewage sludge [32], soil amended with organic waste from sugar mills [65], biochars from peanut shell [29] and slow pyrolysis biochars from vegetal materials [36], respectively.…”