Materials for Renewable and Sustainable Energy

Abstract This study employed low-cost biomass wastes for the synthesis of biodiesel that is cost-effective and environmentally friendly. The major raw material (oil) was obtained by steam distillation (SD) from Croton heliotropiifolius Kunth leaf (CHKL) and was characterized for its aptness for biodiesel production. Dwarft green coconut husk ash (DGCHA) was used as a bio-adsorbent for acid value reduction of Croton heliotropiifolius Kunth leaves oil (CHKLO). A novel, highly potassium-based catalyst was derived from Karpuravalli banana peels (KBP), calcined, and characterized using TGA, ZETA, FTIR, SEM-EDX, XRF-FS, and BET analysis. Biodiesel was synthesized using a microwave-assisted method, characterized, and compared with the recommended standard. The catalytic strength of the calcined Karpuravalli banana peel powder (CKBPP) was tested using a reusability test, and the cost evaluation of production was estimated. Results showed that the CHKL was rich in oil (43% wt./wt.), and the oil is highly acidic (5.23 mg KOH/g oil). At high particle size, the dwarf green coconut husk ash (DGCHA) bagasse reduced the acid value to a minimum (1.4 mg KOH/g oil) at 3 days. The developed novel catalyst from CKBPP indicated high potassium-calcium contents for base transesterification. Process optimization indicated that the predicted response data of 95.285% (wt./wt.) at T1 = 90 min, T2 = 60 oC, T3 = 4.5% (wt.), and T4 = 9 (vol./vol.) was validated in triplicate, and the average data value of 95.10% (wt./wt.) was established. Dataset on the quality of biodiesel showed that the produced biodiesel properties were in line with recommended standards. Economic appraisal data showed that the cost of producing 20 L of CHKLOB (biodiesel) was $4.73 at 1,500 to $1. The study concluded that the production of biodiesel from waste can be cost-effective and environmentally friendly if wastes are harness. Graphical Abstract

Abstract Here, we describe the analysis of the capacitive performance of activated carbon materials derived from the biowaste of lemon. Lemon peel discarded by restaurants after juice extraction is carbonized at 400 0C followed by chemical activation using ZnCl2. The porosity of carbon materials is tailored by varying activation conditions, such as the mass ratio of carbonized lemon peel and ZnCl2, duration of heating, and temperature. The Brunauer–Emmett– Teller (BET) surface area and pore volume of carbon materials prepared at different activating conditions range from 1380 to 2120 m2g−1 and 0.38 to 0.69 cm3 g−1 respectively. The derived carbon materials are amorphous indicated by the broad peaks in the XRD pattern as well as disordered structure of the carbon materials is revealed by the Raman spectroscopic analysis. The systematic analysis of capacitive performance of activated carbons by employing electrochemical techniques like Cyclic Voltammetry (CV), Galvanostatic charge/Discharge (GCD) cycles, and electrochemical impedance spectroscopy (EIS) in acidic (H2SO4) and alkaline (KOH) media indicates that optimum condition for activation of lemon peel is 600 °C for 60 min with 1:1 mass ratio of carbonized lemon peel and ZnCl2. The superior performance of (ALP-600) is attributed to its high surface area and well-connected hierarchical porous structure. The tiny hump at ~ 0.2 V in CV might be due to the pseudocapacitive nature of oxygen functional groups indicated by FTIR. ALP-600 exhibits the highest specific capacitance of 180 Fg−1 and retains 99.7% of its initial capacitance after 5000 cycles in the acidic electrolyte. The maximum capacitance achieved with ALP-600 symmetric cell in CR2032 coin cell configuration is 0.90F.

Abstract In the ongoing quest for sustainable construction practices, the exploration of innovative materials is paramount, and cork has emerged as a remarkable eco-friendly building material with vast untapped potential. Cork, harvested from the bark of cork oak trees without harming them, possesses a unique combination of qualities that make it an ideal candidate for environmentally conscious construction. Cork is exceptionally renewable and biodegradable. What makes cork even more promising is its compatibility with various existing construction materials, including cement, plastic, and plywood. By integrating cork with these materials, we can improve their structural integrity, thermal performance, and acoustic insulation, while reducing their environmental impact. By harnessing the potential of cork and seamlessly merging its exceptional performance with a planet-conscious approach, the construction industry can significantly reduce its ecological footprint. Cork emerges as a compelling contender in shaping a greener, more resilient construction landscape, offering a sustainable alternative that aligns with our growing commitment to environmentally responsible building practices. This eco-friendly material not only benefits the environment but also enhances the overall quality and sustainability of our built environment.

Abstract Sulfonated poly (ether ether ketone) (SPEEK) has received substantial attention for its potential to improve the electrochemical behavior and thermomechanical capabilities of direct methanol fuel cells. This study examines how the integration by solution casting of microcrystalline cellulose (MCC) and 2,3-dialdehyde cellulose (DAC) onto highly sulfonated PEEK (with a sulfonation degree of 80%) affects its physicochemical properties and morphological structures. The mechanical attributes and proton conductivity of the polymer matrix are impacted by MCC and DAC inclusion into SPEEK membrane. The maximum proton conductivity was seen in the SPEEK/MCC membranes at 70 °C (up to 0.1 S cm−1). The proton conductivity in methanol vapor was increased by SPEEK/DAC membranes at high temperatures as opposed to pristine SPEEK and SPEEK/MCC membranes.