Utilizing a novel metal-organic framework for clean water production: Synergistic evaporation boost in double slope distiller

Abstract

This study experimentally investigates the integration of Fe-Co-Al @ BTC Metal-Organic Framework (MOF) into a double slope solar still (DSSS) to enhance the evaporation rate. Three configurations were tested: MOF as a nanofluid in the basin water (Case I), MOF as a nanofluid with an atomizer (Case II), and MOF for thin film evaporation (Case III). A comprehensive 4E analysis—Energy, Exergy, Economic, and Environmental—evaluated the performance of the DSSS relative to conventional solar still (CSS). The MOF improved DSSS performance through its superior thermal properties and large surface area. Performance results showed notable improvements. Energy efficiency increased significantly, with Case III improving by 103 %, Case II by 82.3 %, and Case I by 53.3 %. Exergy efficiency witnessed more dramatic enhancements, with Case III rising by 162 %, Case II by 137 %, and Case I by 70.6 %. Accumulated distillate followed a similar pattern, with Case III rising by 92.12 %, Case II by 68.54 %, and Case I by 34.66 %. Case III demonstrated the most promising outcomes, achieving the lowest freshwater cost at 0.0122 $/L—a 26.22 % reduction from CSS. Additionally, the MOF integration resulted in CO2 mitigation ranging from 1.49 to 2.2 tons annually, generating carbon credits between 37.13 and 54.94 $/year. © 2025 The Authors