This work investigated low shrinkage curing techniques and characterization of unsaturated polyester (UPE-8340) and vinyl ester (VE-922) reinforced composite. The reinforced polymeric composite was composed using various amounts (0.1 vol.% to 0.5 vol.%) of methyl ethyl ketone peroxide (MEKP) and the proportion of UPE and VE (5 vol.%) was kept fixed throughout the study. The epoxy matrix was formed using a 3D printed acrylonitrile butadiene styrene (ABS) dumbbell shape mold and the specimen was cured in the presence of air and an inner gas (carbon dioxide) using a customized ambient closed chamber system. The influence of MEKP on UPE and VE reinforce composites was studied by investigating curing kinetics, shrinkage, tensile properties, contact angle, and thermal stability. The CO₂-cured results show a significant lower shrinkage rate and higher tensile strength and flexural modulus of UPE and VE reinforced composite articles compared with air-cured reinforced composite. These macro-scale results correlate with the air-cured structure, an un-banded smooth surface was observed, and it was found that the lowest amount of MEKP revealed significant improvement in the contact angle of UPET and VE reinforced composites.

The global water crisis is growing so severe that there is a need for innovative technologies for effective desalination. The utilization of cutting-edge techniques for the treatment of seawater and saline water using membrane distillation (MD) has several advantages that are significant benefits. This study investigates how swirling flow configurations can improve the performance of Direct Contact Membrane Distillation (DCMD) modules. Swirling flow can be used to create turbulence, which lowers temperature polarization (TP) and concentration polarization (CP). This makes it easier for heat and mass to move through the system. An experimental DCMD system has been set up to study the effect of varying permeate flow rates and temperature differences on permeate flux. The results reveal that higher flow rates and temperature differences significantly enhance the overall performance, up to a limit. This study highlights the potential of swirling flow techniques to improve the efficiency and scalability of MD systems in a bid to enhance the desalination or treatment of water.

In this work, a comprehensive shrinkage and tensile strength characterization of unsaturated polyester (UPE-8340) and vinyl ester (VE-922) epoxy matrices and composites reinforced with multiwall carbon nanotubes (MWCNTs) was conducted. The aspect ratio of UPE and VE with methyl ethyl ketone peroxide (MEKP) was kept at 1:16.6; however, the weight of the MWCNTs was varied from 0.03 to 0.3 gm for the doping of the reinforced nanocomposites. Using a dumbbell-shaped mold, samples of the epoxy matrix without MWCNTs and with reinforced UPE/MWCNT and VE/MWCNT nanocomposites were made. The samples were then cured in a typical ambient chamber with air and an inner gas (carbon dioxide). The effect of the MWCNTs on UPE- and VE-reinforced composites was studied by observing the curing kinetics, shrinkage, and tensile properties, as well as the surface free energy of each reinforced sample in confined saline water. The CO₂ curing results reveal that the absence of O₂ shows a significantly lower shrinkage rate and higher tensile strength and flexural modulus of UPE- and VE-reinforced nanocomposite samples compared with air-cured reinforced nanocomposites. The construction that was air- and CO₂-cured produced results in the shape of a dumbbell, and a flawless surface was seen. The results also show that smaller quantities of MWCNTs made the UPET- and VE-reinforced nanocomposites more stable when they were absorbed and adsorbed in concentrated salt water. Perhaps, compared to air-cured nanocomposites, CO₂-cured UPE and VE nanocomposites were better at reducing shrinkage, having important mechanical properties, absorbing water, and being resistant to seawater.

Gas hydrate‐based desalination is a promising energy‐efficient alternative to traditional seawater desalination technologies, yet slow formation kinetics and salt inhibition limit its practical application. This study investigates the effect of bronze particles (91% Cu, 8% Sn, and 1% Mn; ≤1 mm) on CO ₂ gas hydrate formation in natural seawater (38,000 mg/L total dissolved solids [TDSs]), aiming to evaluate their potential as a nontoxic, nanoporous catalytic promoter for desalination applications. Bronze particles were mechanically produced and ultrasonically dispersed in seawater to achieve even suspension. Isochoric experiments were conducted at 40 bar and 2°C in a bench‐scale high‐pressure crystallizer, comparing a bronze‐promoted system against an unpromoted seawater baseline over three consecutive formation‐dissociation cycles. Observations using sapphire windows showed that the bronze catalytic system was faster in forming hydrates compared to the noncatalytic system, with hydrates forming even on the surface of the particles. The bronze‐promoted system generated 28,718 data points over a duration 6.24 times longer than the baseline, demonstrating substantially extended and more stable hydrate formation. The total pressure drops increased by 9.6% to 2.85 bar. In comparison, the mean operating temperature decreased by 20.5% to 15.04°C, indicating improved dissipation of exothermic crystallization heat due to bronze’s high thermal conductivity (≈100 W · m ⁻¹ ·K ⁻¹ ). Peng–Robinson Equation of State (PR‐EOS) analysis confirmed that the fundamental CO ₂ –water phase equilibrium was unaffected by the addition of bronze, with compressibility factors (0.6436 vs. 0.6414) and fugacity coefficients (0.7373 vs. 0.7371) remaining nearly identical across both systems. The kinetic promotion phenomenon is evidenced by the persistent negative rate of change in pressure during material formation and the lack of induction periods, whereas the thermal promotion phenomenon is evidenced by the 20.5% decrease in the average operating temperature. These observations confirm that bronze acts exclusively as a kinetic and thermal promoter without modifying thermodynamic phase boundaries. Unlike conventional chemical promoters, bronze produces no foam and introduces no separation challenges, offering a robust, nonintrusive method to enhance hydrate formation under saline conditions for desalination. For desalination applications, the 9.6% increase in net gas consumption and the enhanced cycling performance imply that, with bronze‐promoted systems, more water may be recovered per cycle while reducing energy usage due to improved heat transfer, and continuous operation can be maintained without chemical separations. Although the results of water quality (efficiency of recovery and salt rejection) are beyond the current scope of the thermodynamic and kinetic study, the increased active cycle time and higher consumption of gas with the bronze alloy may indicate that the formation time will be shorter and throughput higher in the desalination process based on hydrates.