Multiresponse Optimization of Mechanical and Physical Adsorption Properties of Activated Natural Fibers Hybrid Composites

In the current scenario, natural fiber-based biodegradable composites have increased because natural composite fibers are very cheap, biodegradable, lightweight, fireproof, and nontoxic. The present research work was carried out to optimize the mechanical properties of hybrid composites reinforced by Calotropis gigantea and hemp. To achieve these objectives, the following process parameters were determined, and RSM carried out optimization with the Box-Behnken experimental setup at three different levels: compression molding temperature (degrees C), pressure (bar), and time (min). The fibers were pretreated for 4 hours with a 5% NaOH solution to prevent moisture absorption. Regression equations were constructed to evaluate the mechanical properties, and the best process parameters were established. The results reveal that a pressure of 35 bar, a time duration of 7 minutes, and a temperature of 176 degrees C are the best conditions for compression molding. The second aim was to compare CGF and hemp fiber-derived activated carbon adsorbents by determining physical adsorption properties, chemical compositions, and scanning electron microscope. Natural fibers were shown to be ideal candidates for manufacturing mesoporous activated carbon adsorbents with high surface area (1389-1433 m(2)/g), high mesopore percentage (63-68%), and high carbon content (80-87%). Even though hemp activated carbon had a greater mesoporous structure (69%) than CGF-derived activated carbons, the CGF-derived activated carbons had larger surface areas and higher C content.

Automated summary

In the current scenario, the use of natural fiber-based biodegradable composites has increased due to their low cost, biodegradability, lightweight nature, fireproof properties, and non-toxicity. This research focuses on optimizing the mechanical properties of hybrid composites reinforced by Calotropis gigantea and hemp. By optimizing compression molding temperature, pressure, and time, the best process parameters for achieving the desired mechanical properties were determined. Additionally, the physical adsorption properties, chemical compositions, and microscopic structures of activated carbon adsorbents derived from CGF and hemp fibers were compared. The results highlight natural fibers as ideal materials for manufacturing activated carbon adsorbents with high surface area, mesopore percentage, and carbon content.