Effects of Zeolites X and Y on the Degradation of Malathion in Water

Effects of Different Types of Zeolites on the Degradation Kinetics of Malathion Pesticide in Water

“…The concentration of degradation products (DCA and MCA) slightly increased up to 20 h and thereafter, the concentration of MCA decreased till the end of the experiment. These findings concur with the reports of Lalah and Wandiga [23], who described the transformation of malathion in water, with the major metabolites being malathion α-and β-mono-carboxylic and malathion dicarboxylic acid and that by Ogunah et al [16]. Such a trend as witnessed in Fig.…”

“…The sodium-exchanged Faujasite X (NaX) zeolite (Si/Al<2.5) was reported to be more effective in the degradation and adsorption of Malathion and its residues than Faujasite Y (NaY) zeolite (Si>2.5), and the degradation products were dependent on the type of the zeolite used. The observed variance in performance of the two FAU zeolites was attributed to the zeolites' Si/Al ratios since the zeolites had comparable pore diameters [16]. Both the NaX and NaY zeolites significantly enhanced the malathion degradation kinetics, corroborating previous findings [11].…”

“…In a separate study, appreciable changes in unit cell parameters, of the Faujasite Y zeolite following adsorption of the different solutes (sulfonamides) were reported [19]. Similar findings of variation in structural modifications were observed for different zeolites (X and Y) treated with the same malathion adsorbate [16]. These findings underscore the need for a concise comparative investigation of the underlying driving factors of zeolite-catalyzed degradation reactions in pursuit of a selected zeolite with favorable kinetics and adsorption potential for malathion degradation.…”

“…For each replicate, the operational pH of the solutions was measured. At pre time intervals (30 min, 60 min, 90 min, 24 h, 48 h, 60 h, and 72 h), 2 mL aliquots were obtained from the reaction vessels for residual malathion analysis by GC-MS as described by Ogunah et al [16]. Noteworthy, the malathion recovery ranged from 80.3% to 125.9% (0.1 or 1.0 mg kg spiking level), and the linear range of detection was from 0.1 to 8.…”

“…Despite these studies, adsorption is still the widely used technique for the removal of organic contaminants from water due to its simplicity, efficiency, and techno-economic advantages [12]. Several studies have evaluated possible alternative adsorbents such as eggshells, fly ash, zeolites, and clays for malathion removal from water [13][14][15][16][17]. Of particular interest, is the use of zeolites for malathion degradation or sequestration because the structure, properties, and chemistry of zeolite interaction with organic molecules such as pesticides are very specific, arguably complex, and not well understood.…”