REMOVAL OF DELTAMETHRIN FROM WATER BY USING AFRICAN WALNUT SHELLS (AWS) /
OBA OLUWASUYI AYOBAMI; SUPERVISOR: ASSOC. PROF. DR. NUR PAŞAOĞULLARI AYDINLIK
- 134 sheets; 31 cm. Incudes CD
Thesis (PhD) - Cyprus International University. Institute of Graduate Studies and Research Environmental Engineering Department
Includes bibliography (sheets 121-132)
ABSTRACT Water contamination has been an environmental concern from the last decades when both organic and inorganic chemical contaminants have found their way into the environment. With the rise in industrialization, the use of pesticides in agriculture have increased and as well contributed to the build-up of contamination in water bodies. This research was aimed at producing a novel activated carbon from agricultural waste by-product African walnut shells (AWS) to remove deltamethrin from water. Novel African Walnut Shell (AWS) was treated and improved as an agricultural waste by-product to produce high surface area activated carbon via chemical activation with potassium hydroxide (KOH) to achieve extremely effective adsorptive characteristics for deltamethrin removal. The adsorbent (KOHAWS) was characterized by scanning electron microscopy (SEM) analysis, Fourier Transform Infrared (FT-IR) spectroscopy, the Brunauer-Emmett-Teller (BET) surface area and pH point of zero charge (pHPZC). The batch sorption was studied under equilibrium conditions at pH 6, agitation speed of 150 rpm, 5 ppm initial concentration; 90 minutes contact time, and 1 g of adsorbent dosage. Batch sorption experiments were investigated to study the effect of pH, initial concentration and contact time, sorbent dosage and agitation speed. The results reveals that the experimental data fitted well with Langmuir isotherm model (R2 = 0.997) with maximum adsorption capacity at 57.64 mg. g-1 and the kinetic of the sorption follows the pseudo-first order model (R2 = 0.995). The sorption of deltamethrin onto KOHAWS reveals a high removal efficiency of 98.2%. The findings show that the Novel AWS has excellent regeneration and reusability properties and may be used to remove pesticides from aqueous solutions instead of conventional activated carbon.