Water vapor harvesting by a (P)TSA process with MIL-125(Ti)_NH2 as adsorbent

Abstract The potential of the MIL-125(Ti)_NH2 for water (H2O) capture from air is assessed in the present study. To achieve this goal, the adsorption affinity of the material towards different adsorbates, and its subsequent regeneration in adsorption/desorption cycles, were evaluated. Adsorption equilibrium isotherms were measured in a temperature range between 283 and 323 K and pressure between 0 and 7 bar. Water vapor presented isotherms of Type V and were fitted by applying the Cooperative Multimolecular Sorption (CMMS) model and Polanyi’s theory model. Breakthrough experiments of water vapor corroborated that the adsorption equilibrium isotherm is of Type V. Diffuse Reflectance Infrared Fourier Transform Spectroscopy (DRIFTS) analysis revealed a high capability of regeneration during the adsorption/desorption cycles. The pressure-temperature swing adsorption (P)TSA proposed process shows a maximum productivity of 320 l·day-1·ton-1, considering a regeneration temperature of 373 K, and condensate the outlet stream during the regeneration step at 283 K.