Impregnated fibrous ammonia chemisorbent based on citric acid. Prediction of protective characteristics

Abstract

The influence of relative humidity (RH) of the gas-air environment on the ammonia chemisorption by impregnated fibrous chemisorbent (IFCS) is studied. IFCS was obtained by impregnating nonwoven needle-punched material from polyester fibers with an aqueous solution of citric acid (40 w%) with modifiers (glycerin, sodium chloride and ethanol) to uniformly distribute the chemisorbent on the surface of the fibers and increase adhesion to the composition of the impregnating solution. It is shown that for all values of relative humidity the curves of ammonia breakthrough through a fixed layer of IFCS спр(tпр) in the coordinates ln(c0/спр -1), tпр are reliably R2 > 0.95 approximated by straight lines and the Wheeler-Jonas theoretical model can be used for the quantitative description of the ammonia-IFCS system. By comparing the experimental and theoretical curves спр(tпр) in the coordinates ln(c0/спр -1), tпр the unknown model parameters were determined: the chemisorption rate constant and the sorption capacity of the IFCS unit mass and their dependence on the relative humidity of the gas-air environment (GAE). It has been established that the IFCS sorption capacity increases linearly with increasing, and the chemisorption rate constant of the ammonia-IFCS system does not depend on the GAE relative humidity and is equal to . The influence of the GAE relative humidity and the thickness of the IFCS layer on the ammonia breakthrough time is experimentally investigated and the adequacy of using the Wheeler-Jonas model for predicting the service life of IFCS for real use conditions is substantiated.