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In this study, the impact and flexural properties of woven basalt fiber/phenolic (BFP), woven carbon fiber/ phenolic (CFP) and woven basalt/woven carbon hybrid phenolic (BCFP) composites are investigated. The hybridization effect of woven basalt and woven carbon fibers on the impact energy absorption and flexural properties is investigated for various weight ratios of basalt/ carbon hybrid fibers such as 1:0, 0.83:0.17, 0.68:0.32, 0.61:0.39, 0.34:0.66 and 0:1. It is found that the impact properties of the composites are strongly improved when the basalt fiber increased. Impact energy absorption of CFP composite showed a regular trend of increase with increasing weight ratio of basalt fiber in hybrid fiber composite. The lowest impact energy absorption values are found for the composites with weight ratio 0:1 (CFP), with average of 70 kJ/m 2 . Corresponding values for energy absorptions are obtained for 0.83:0.17, 0.68:0.32, 0.61:0.39, 0.34:0.66 basalt/carbon weight ratio in hybrid composites. The impact energy absorption of hybrid composites (BCFP) shows the highest value with an average of 219 kJ/m 2 , when the weight ratio of 0.83:0.17 is used. Finally, the impact energy absorption of BFP composites with the weight ratio of 1:0 shows the highest value of 268 kJ/m 2 . The experimental evidence shows that the hybrid composites based on combinations of stiff carbon fibers and tough basalt fibers have good flexural properties and therefore, they can be used as promising materials in a number of engineering sectors such as the protective structures.

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Herein, an efficient adsorbent based on an activated carbon and metal−organic framework was developed for the adsorption of heavy metals from an aqueous solution. The structural and morphological characterizations of the Cr-MOF/ AC composite were evaluated by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM), exhibiting the formation of crystalline cubicshaped particles. The Cr-MOF/AC composite showed 3-fold higher specific surface area (2440 m 2 /g) than AC. The response surface methodology was employed to find the optimum adsorption conditions for the fast and efficient removal of lead and cobalt ions. The study of the kinetics of adsorption showed that the metal ions adsorption followed the pseudo-second-order model. The resultant composite was proved to be an excellent and highly efficient adsorbent with the adsorption capacity as high as 127 and 138 mg/g for lead and cobalt, respectively, under optimal conditions (pH = 5, an adsorption time of 40 min, adsorbent content of 25 mg, and metal ion concentration of 70 ppm). A further investigation on the reusability of adsorbent was also carried out, demonstrating the almost unchanged structure of the Cr-MOF/AC composite after five regeneration cycles. The Cr-MOF/AC composite exhibits a great potential for heavy metal adsorption and wastewater treatment.