The effect of synthesized NPK loaded surfactant modified zeolite a based fertilizer in tomato (lycopersycum esculentum ) cultivation

Abstract

The surface of zeolite Asynthesised from Ahoko kaolinwas optimally modified by quaternaryammonium compound, HDTMA and used as fertilizer carrier.Characterization techniques such asFTIR and BET were used to characterise the zeoliteA and modified zeolite Asamples.Zeolite A’smaximum adsorption capacityof 7.55mg/gwas obtained withinitial concentration of 162.6 mmol/L, contact timeof16 h, and temperatureof25oC. The initial HDTMA concentration wasthe most significant term that influencedthe adsorption capacity of zeolite A.The interactive effect that contributedsignificantlyto the maximum adsorption capacity (6.27mg/g)of the zeoliteoccurred with initial HDTMA concentration (243.80mmol/L) and adsorption temperature of 25.21oC as predicted by the Design Expertsoftwareversion 7usedfor thework.The surfactant modification ofthe surface of zeolite A reversedthe negative charges on the framework to positive and allowedthe adsorption of oxyanions such as nitrates and phosphates. Theresults indicated areduction in the BET surface area of HDTMA modified zeolite A from65 to 46.72m2/g and 62.27m2/g for phosphateloadedzeolite A and nitrate loaded zeolite A based fertilizersrespectively.Conventional NPK 15:15:15 and the NPK loaded zeolite A based fertilizerwereappliedon tomato crop. The resultofa higher leaf count(growth parameter)ofzeolite A based fertilizer withmean (54.2) compared withNPK 15:15:15 with mean (25.7)at 11 WAT indicated the slow release property andnutrientretentionof zeolite A based fertilizer. The zeolite A based fertilizertreated plantshad a higher fruit yield with mean (84.69)compared with NPK 15:15:15 fertilizer with mean (69.34).