Study On The Dissolution Characteristics Of Sulfuryl Fluoride In Bio-based Solvents

Due to the prohibition of traditional fumigant bromomethane and the high temperature and explosive hazard of ethylene oxide,sulfuryl fluoride?SO₂F₂?,as a substitute,has been widely used in warehouses,cargo ships,containers,buildings and other fields due to its excellent properties.Meanwhile,the greenhouse effect and health hazards of sulfuryl fluoride have gradually attracted people's attention.In view of the current situation of sulfuryl fluoride exhaust gas discharged directly into the atmosphere after fumigation,it is urgent to develop a green treatment method for sulfuryl fluoride.This paper puts forward a method for sulfuryl fluoride treatment based on.The effect of type and number of functional groups of the bio-based solvents on the performance of sulfuryl fluoride dissolution was studied.The solubilities of sulfuryl fluoride in various bio-based solvents were correlated using SRK state equation and PR state equation in combination with the van der Waals single-parameter mixing rules.The models of sulfuryl fluoride solubilities in bio-based solvents were developed.The main findings are as follows:Firstly,a set of experimental apparatus based on constant volume method was designed and built according to the physical and chemical characteristics of sulfuryl fluoride.Secondly,the solubilities of sulfuryl fluoride in fourteen bio-based solvents such as dipropyl malonate and methyl nonanoate were studied by constant volume method at temperature 20-50?and pressure 0-600 kpa.The results showed that,compared with hydroxyl group,carboxyl group,ketone group and aldehyde group,the ester group was beneficial to the dissolution of sulfuryl fluoride.The increase in the number of ester groups favored the dissolution of sulfuryl fluoride.Among the fourteen bio-based solvents studied,tributyl citrate has good solubility of sulfuryl fluoride and can be used as the optimal sulfuryl fluoride absorbent.In addition,the Henry constant Ex of sulfuryl fluoride in the above bio-based solvents at 20-50?was calculated using the measured solubility data,which was between 2.21 and 11.03 MPa.Based on the correlation between Henry's constant Ex and temperature T,the standard Gibbs free energy,enthalpy and entropy changes for the dissolution of sulfuryl fluoride in bio-based solvents were further obtained.The enthalpy change was in the range of 10.13 k J/mol to 17.28 k J/mol,which belongs to the van der Waals force.Finally,the solubility data of sulfuryl fluoride were fitted using SRK equation of state and PR equation of state combined with van der Waals single-parameter mixing rule.The binary interaction parameter k_ij of SRK equation and PR equation was obtained.Furthermore,the correlation between the binary interaction parameter k_ij and temperature T was determined using cubic polynomial equation.The results show that the SRK model and PR model have high accuracy in predicting the solubility of sulfuryl fluoride in bio-based solvents.The precision of the two models is similar,with the average relative deviation between 0.48%and 1.39%.