Utilization of clay based super-porous hydrogel composites in atmospheric water harvesting

Hemant Mittal, Ali Al Alili, Saeed M. Alhassan

Research output: Contribution to journalArticlepeer-review

4 Scopus citations

Abstract

Current research work reports the synthesis and performance evaluation of solid polymer desiccant materials based on the superporous hydrogel composites (SPHCs) comprising superporous hydrogel (SPHs) of sodium acrylate (SA) and acrylamide (AM) with different clays such as Laponite®, bentonite and palygorskite. Synthesized polymer desiccants were characterized using SEM, XRD, TGA and FTIR techniques. All the polymer desiccants followed type-III isotherm and the experimental data correlated well with Guggenheim, Anderson and Boer (GAB) model and suggested that these desiccants belong to macroporous adsorbents and adsorb water vapors largely via capillary condensation process. Parental SPH (i.e. P(SA-co-AM)-SPH) and different SPHCs i.e. SPHC-Laponite®, SPHC-bentonite and SPHC-palygorskite exhibited maximum adsorption capacities of 0.12, 0.17, 0.15 and 0.14 gw/gads, respectively at 50% relative humidity and 25 °C, however, at 90% relative humidity adsorption capacities increased upto 0.77, 1.05, 0.93 and 0.87 gw/gads, respectively, which suggested that the hydrophilicity of synthesized desiccants increased with increasing relative humidity. Exceptionally high adsorption capacities of these desiccants were because of the combined effects of highly porous structure of SPHs and hydrophilic nature of clays. Furthermore, experimental kinetics data correlated well with linear driving force model and suggested that the diffusion of water within polymer structure was via type-II diffusion mechanism. During multiple cycle adsorption, SPHCs exhibited much better re-use efficiency than SPHs which suggested that the incorporation of clays within the polymer matrix not only improved desiccant performance but also improved re-use efficiency of polymer desiccants.

Original languageBritish English
Article number106712
JournalApplied Clay Science
Volume230
DOIs
StatePublished - 15 Nov 2022

Keywords

  • Solid polymer desiccants
  • Super-porous hydrogels
  • Water vapors adsorption

Fingerprint

Dive into the research topics of 'Utilization of clay based super-porous hydrogel composites in atmospheric water harvesting'. Together they form a unique fingerprint.

Cite this