Environmental behavior assessment Thiophanate methyl in the soil using different mathematical models

One of the most common fungicides, Thiophanate-methyl (TM), has been extensively used to prevent fusarium wilt disease. Understanding the kinetic behavior of the TM-fungicide in the greenhouse soil was aimed at the current research. The findings demonstrated that TM-fungicide goes through the pseudo-first-order model (PFO), which results in a rate constant K= 0.421 minutes-1. As a result, TM-fungicide needs 16.46 minutes-1 to degrade 50% of the initial concentration. The power function for TM-fungicide ranged from -1.826 to 0.0360 minutes-1, and the distribution coefficient was 6.5 mL g-1. Regarding the adsorption of Langmuir and Freundlich, TM-fungicide is more fitting to the Freundlich with the aF = 25.73 and the bF = 0.078 compared to the Langmuir model. The TM-fungicide starts to release to the soil after 4-5 hours, achieving extensive, effective control of the soil pests, Moreover, TM-fungicide is highly mobile in the soil based on the current conditions.