Assessing Exergy Efficiency in Computer-Aided Modeled Large-Scale Production of Chitosan Microbeads Modified with Thiourea and Magnetite Nanoparticles

Abstract

Chitosan, the deacetylated derivative of chitin, is a biopolymer with many applications in different sectors, such as pharmaceutical, food, and wastewater treatment, amongst others. It can be used as a source for synthesizing bioadsorbents modified with chelators and nanoparticles for the removal of pollutants. In this report, we conducted an exergy analysis to evaluate the large-scale production of chitosan-based bioadsorbents modified with iron nanoparticles and chelators. The objective was to identify energy inefficiencies and propose technological enhancements to improve energy utilization. The process was simulated using Aspen Plus V.10® software, enabling the quantification of chemical and physical exergies for the species and streams involved. We calculated process irreversibilities, exergy losses, waste exergy, and utility exergy flows for each stage and the overall process. These findings provide valuable insights into optimizing energy utilization in the production of chitosan-based bioadsorbents. The overall exergy efficiency was 4.98%, with the washing and drying stages of nanoparticles and adsorbent synthesis accounting for the largest contribution to process irreversibilities and exergy destruction. To increase the global exergy efficiency of the process, it is proposed to implement process improvement strategies, such as mass or energy integration, to obtain better energy performance.