Pyrolysis has been demonstrated to be a highly effective thermochemical process for converting complex biomaterials into biochar and syngas rich in hydrogen. The pyrolysis of mixed date palm seeds from Saudi Arabia was conducted using a fixed-bed pyrolyzer that was custom made for the purpose. The influence of the pyrolysis temperature (200–1000 °C) on the various physicochemical parameters of the date seed biochar generated through the pyrolysis process and the hydrogen-rich syngas was investigated. Proximate and ultimate analyses indicated a high carbon content in the lignocellulosic constituents such as cellulose, hemicellulose, and lignin. Using energy-dispersive X-ray (EDX) analysis, it was discovered that the elemental composition of biochar changes with the pyrolysis temperature. The date seeds pyrolyzed at 800 °C were found to have the maximum carbon concentration, with 97.99% of the total carbon content. The analysis of the biochar indicated a high concentration of carbon, as well as magnesium and potassium. There was a potential for the production of hydrogen-rich syngas, which increased with the pyrolysis temperature. At 1000 °C, the highest hydrogen and carbon monoxide compositions of 40 mol% and 32 mol%, respectively, were obtained. The kinetic data of the date seed pyrolysis were fitted using linearized model-free methods, such as Friedman, Flynn–Wall–Ozawa (FWO) and Kissinger–Akahira–Sunose (KAS), as well as non-linear methods such as Vyazovkin and advanced Vyazovkin. The activation energies obtained from Friedman, FWO, and KAS varied in the range of 30–75 kJ/mol, 30–65 kJ/mol, and 30–40 kJ/mol, respectively, while those of Vyazovkin and advanced Vyazovkin were found in the range of 25–30 kJ/mol, and 30–70 kJ/mol, respectively. The analysis showed that the FWO and KAS models show smaller variation compared to Friedman.

The discharge of textile wastewater into aquatic streams is considered a major challenge due to its effect on the water ecosystem. Direct blue 78 (DB78) dye has a complex structure. Therefore, it is difficult to separate it from industrial wastewater. In this study, carbon obtained from the pyrolysis of mixed palm seeds under different temperatures (400 °C and 1000 °C) was activated by a thermochemical method by using microwave radiation and an HCl solution in order to improve its adsorption characteristics. The generated activated carbon was used to synthesize a novel activated carbon/chitosan microbead (ACMB) for dye removal from textile wastewater. The obtained activated carbon (AC) was characterized by a physicochemical analysis that included, namely, particle size, zeta potential, SEM, EDX, and FTIR analyses. A series of batch experiments were conducted in terms of the ACMB dose, contact time, pH, and activated carbon/chitosan ratios in synthetic microbeads for enhancing the adsorption capacity. A remarkable improvement in the surface roughness was observed using SEM analysis. The particle surface was transformed from a slick surface with a minor-pore structure to a rough surface with major-pore structure. The zeta potential analysis indicated a higher improvement in the carbon surface charge, from −35 mv (before activation) to +20 mv (after activation). The adsorption tests showed that the dye-removal efficiency increased with the increasing adsorbent concentration. The maximum removal efficiencies were 97.8% and 98.4% using 3 and 4 g/L of AC_400°C MB-0.3:1 and AC_1000°C MB-0.3:1, respectively, with initial dye concentrations of 40 mg/L under acidic conditions (pH = 4–5), and an optimal mixing time of 50 min. The equilibrium studies for AC_400°C MB-0.3:1 and AC_1000°C MB-0.3:1 showed that the equilibrium data best fitted to the Langmuir isothermal model with R² = 0.99. These results reveal that activated carbon/chitosan microbeads are an effective adsorbent for the removal of direct blue 78 dye and provide a new platform for dye removal.

Biochar is gaining recognition as a sustainable material, with several applications in soil amendment, carbon sequestration, nutrient dynamics, the remediation of organic contaminants from soil, and water filtration. However, understanding its characteristics is limited due to its intricate structure. This study used response surface methodology (RSM) and artificial neural networks (ANNs) to optimize and predict the production of biochar from the pyrolysis of palm kernel shells. To determine how residence time, nitrogen flow rate, and pyrolysis temperature affected biochar production, a Box–Behnken experimental design was employed. The prediction of the biochar yield was modeled using four different models of ANNs: narrow, medium, wide, and optimum. The physicochemical properties of the biochar produced at pyrolysis temperatures ranging from 400 to 800 °C were determined using X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDX), nitrogen (N₂) physisorption analysis, and field emission scanning electron microscopy (FESEM). With a p-value significantly lower than 0.05, the response surface quadratic model was found to be the most suitable to optimize the biochar yield obtained from the PKS pyrolysis. Biochar production was very sensitive to the three operating parameters: pyrolysis temperature, nitrogen flow rate, and pyrolysis time. With a coefficient of determination (R²) of 0.900, root mean square error (RMSE) of 0.936, and mean absolute error (MAE) of 0.743, the optimized ANN outperformed the other three ANN models tested. When compared to the optimized ANN, the response surface quadratic model with an R² of 0.989 had better prediction of biochar yield. At optimized experimental conditions for nitrogen flow rate (150.01 mL/min), temperature (799.71 °C), and pyrolysis time (107.61 min), a biochar yield of 37.87% was obtained at a desirability function of 1.

It is compulsory for final-year undergraduate engineering students to take a senior design class, commonly known as the senior capstone design project. This project is set up to help students deeply understand and apply what they have learned since beginning their quest for a bachelor’s degree in science. Capstone preparation involves many elements including the contribution of faculty members and academic programs that give students the technical and management skills needed to establish a career in engineering. Moreover, the capstone usually requires funding, which often comes from the industry sector. The engineering faculty at King Abdulaziz University (KAU) encourages students to complete this course showing high-quality levels of achievement. The university’s mechanical engineering department led the effort in organizing the senior design project course, which meets the Accreditation Board for Engineering and Technology (ABET) requirements. This paper presents an overview of a program that promises an outstanding engineering capstone experience for two KAU engineering colleges in Rabigh and Jeddah, Saudi Arabia. This paper delineates the process, leadership skills, ABET involvement and evaluation. The capstone project presented here has provided overall satisfaction from both faculty members and students. Moreover, course management improvements led to a more cost-efficient program.

Cold thermal storage can be used to manage peak load when the energy demand is exceeding the capacities of the electric companies. Latent heat thermal storage is more effective because it requires less spacing and has higher thermal capacity than other types. Solidification and melting are taking place in CTS and need more investigation for better performance. Phase change materials properties vary and need more investigation to select the most suitable for a certain application. The analytical equations are needed for design of CTS and get the maximum efficiency out of it. Cost effectiveness is also described.