Palm oil mesocarp fiber (POMF), a lignocellulosic biomass generated in large quantities during palm oil production, is a potential feedstock for sugar production via steam explosion. In this study, the steam explosion of POMF was simulated using Aspen Plus® to evaluate the effects of POMF composition, steam explosion temperature (110–220°C), and residence time (3.5–20 min) on cellulose and hemicellulose conversions as well as on the yields of sugars and degradation products. Variations in POMF composition had no significant impact on cellulose or hemicellulose conversion, nor on the resulting product yields. Across all samples, glucose yields remained constant at approximately 14%, while xylose yields remained stable at approximately 6%. Furfural and 5-HMF yields were minimal at ~0.5% and ~0.2%, respectively. In contrast, product yields were highly sensitive to steam explosion temperature. Glucose yield increased moderately from ~12.7 to ~14.3% at intermediate temperatures before declining sharply between 170 and 210°C. Xylose increased from 0.47 to 10.1% as the temperature rose from 130 to 160°C, then decreased substantially at higher temperatures. At elevated temperatures, sugars became unstable and degraded, leading to significant increases in furfural and 5-HMF formation above 160°C. Residence time had a stronger influence than temperature. Prolonged exposure intensified sugar degradation, with glucose decreasing from ~14.1 to 2.3% and xylose decreasing to 1.4% as residence time increased from 3.5 to 20 min. Correspondingly, furfural and 5-HMF yields increased gradually with time, indicating enhanced secondary degradation pathways. Overall, the Aspen Plus® model successfully described the steam explosion behavior of POMF over a wide range of process conditions. While POMF composition exerted minimal influence, both steam explosion temperature and residence time strongly affected sugar release and the formation of degradation products.

Microalgal polysaccharides represent a high-value class of bioactive macromolecules with growing demand in pharmaceutical, nutraceutical, and functional food industries. Yet, inefficient and unsustainable extraction technologies severely constrain their industrial exploitation. Chlorella pyrenoidosa is a particularly attractive biomass source due to its rapid growth and high polysaccharide content, but its highly recalcitrant cell wall remains a major barrier to efficient recovery. The objective of this study was to optimize microwave-assisted extraction (MAE) conditions to maximize polysaccharide yield from Chlorella pyrenoidosa and to evaluate the effects of critical process variables using response surface methodology (RSM). Accordingly, a Box–Behnken experimental design was employed to systematically model and optimize the effects of extraction temperature, solid-to-liquid ratio, and irradiation time. Under optimized conditions (60 °C, 1:80 g/mL, 10 min), a maximum polysaccharide yield of 60.22% was achieved. The quadratic regression model exhibited excellent predictive accuracy (R² = 0.9893, p < 0.05), as confirmed by ANOVA. Compared with conventional extraction methods, the optimized MAE process delivered markedly higher extraction efficiency, substantial reductions in processing time and solvent usage, and superior alignment with green chemistry principles. Collectively, this work provides a scalable and industrially relevant green extraction framework that advances the valorization of microalgal biomass and supports the transition toward sustainable biorefinery platforms.

A hydroponic planting technique employing organically treated anaerobic digestion digestate liquid fertiliser is becoming popular. This study examines the biological treatment of digestate from food processing waste anaerobic digestion using Cosmoball® uncoated and activated carbon-coated plastic media. In a pilot-scale recirculating hydroponic system (RHS), ammonia-to-nitrate conversion and plant development were assessed at varying digestate ammonia concentrations. Bench tests suggest that AC-coated Cosmoball® successfully treats digestate. After 21 days, the nitrate level reached 80 ppm, and 100% ammonia elimination and over 90% of the carbon oxygen demand (COD) were observed. The RHS maintained 116-ppm nitrate but reduced COD treatment to only 62–66%. High pH at the start of the RHS trial required pH control until day 40, after which it stabilised at 6.8. 15-ppm ammonia additions caused a substantial pH drop. Maintaining the pH at 5.8 on the RHS boosted plant growth. Finally, AC-coated media improves nitrification and produces plant-growth nitrate.

Photocatalytic oxidation is an effective method for degrading organic pollutants in air and water, but suspended photocatalysts, such as titanium dioxide (TiO2), face challenges including recovery difficulties, a large band gap, and a low surface area. In this study, titanium oxide and mesoporous siliceous phosphotungstic acid (TiO2-MPTA) were incorporated into polyvinylidene difluoride (PVDF) membranes as an alternative to bare TiO2 for methylene blue (MB) removal. Both opaque (O-PVDF/TiO2-MPTA) and translucent (T-PVDF/TiO2-MPTA) membranes were fabricated with TiO2 loadings of 0.5–2.5 wt.% via blending, with translucency designed to enhance light penetration for improved photocatalytic activity. Membranes were characterized by SEM, FTIR, and UV-vis-NIR spectroscopy to assess morphology, chemical composition, and optical properties. Photocatalytic performance was strongly dependent on TiO2-MPTA content. Neat T-PVDF and O-PVDF showed negligible MB removal (~0.8% and ~0.7%, respectively) due to the absence of a photocatalyst. MB degradation increased with loading, reaching 74% for T-PVDF/1.5TiO2-MPTA and 59% for O-PVDF/1.5TiO2-MPTA, before declining at 2.5 wt.% due to catalyst agglomeration. The translucent T-PVDF/1.5TiO2-MPTA membrane outperformed its opaque counterpart by 15%, highlighting the role of light penetration. Enhanced performance is attributed to the mesoporous structure and high surface area (154–625 m²/g) of MPTA-Si, which provides abundant active sites, promotes photon absorption, and reduces electron-hole recombination. These results demonstrate that PVDF/TiO2-MPTA nanocomposite membranes, particularly translucent membranes with optimized loading, are promising for efficient photocatalytic removal of organic dyes from wastewater.

The energy crisis and environmental impacts of fossil fuels encourage the development of environmentally friendly alternative energy sources. Hydrogen is a promising candidate as a future energy carrier. This research aims to optimize hydrogen production through seawater electrolysis using Ni–Mo/Cu electrodes with a photovoltaic energy source. Ni–Mo/Cu electrodes were prepared via electrodeposition at a varied durations of 2, 4, and 6 minutes. Electrode characterization was conducted using X-Ray Diffraction (XRD) and Scanning Electron Microscope-Energy Dispersive X-Ray (SEM–EDX). Photovoltaic systems were designed using fuzzy logic to optimize solar energy absorption. The electrolysis process was carried out at voltages of 10–30 V. The results showed that a 4-minute electrodeposition produced the most significant Ni–Mo layer. The highest hydrogen production rate of 0.7417 cm³/s was obtained at 25 V using a Ni–Mo/Cu electrode. These findings demonstrate the feasibility of producing hydrogen from seawater using renewable energy sources under the studied conditions.

Biogas has emerged as a promising sustainable resource due to its abundant methane content, which can be converted into valuable chemicals. This study investigates benzene production from biogas using a Mo/HZSM-5 catalyst in a packed bed reactor, aiming to provide an alternative feedstock for the petrochemical industry. A process model was developed using DWSim software to simulate and optimize the benzene production process. The simulation demonstrated that with a biogas feed of 7.5 kiloton/year, benzene production reached 1.2 kiloton/year, yielding 0.16% with a reactor conversion efficiency of 43.89%. Key process parameters were analyzed to ensure feasibility and sustainability, including energy consumption (0.6 MW heating, 0.8 MW cooling, and 0.2 MW electricity). The separation of CO₂ and light gases was achieved using a mixed-matrix membrane, followed by benzene purification through absorption and distillation, achieving a final purity of over 98%-mol. Compared to conventional benzene production methods from shale gas or LPG, this process offers lower energy requirements and improved yield, making it a viable approach for industrial implementation. This study not only presents a detailed simulation but also highlights the potential of biogas as a renewable feedstock for benzene synthesis, contributing to sustainable chemical production. Further techno-economic analysis and experimental validation are recommended to assess scalability and commercial feasibility.

Crystal size distribution (CSD) is an essential criterion for determining the production of high-quality crystals since it influences the efficiency of the crystallization process. Producing specified CSD in the crystallization process represents a main challenge as it depends on temperature control, which indirectly regulates the solution’s concentration and affects the crystal’s evolution. Different temperature profiles may influence the distribution of crystal products, and a suitable optimization algorithm is required to produce an optimum temperature trajectory that produces the desired CSD. Thus, this study aims to maximize the CSD of the grown seed crystals while minimizing the nucleus-grown crystals by employing the best optimization algorithm for the potash alum crystallization process. The crystallization process was developed and simulated in Matlab software using a potash alum in the water system. Four optimization algorithms were proposed with different objective functions, such as maximizing mean crystal size (I), minimizing coefficient of variation (II), minimizing nucleus-grown crystals (III), and maximizing CSD (IV). Based on the simulation results, optimization IV, which maximizes CSD, performs best with a large mean crystal size of 490 µm. Furthermore, the number of fine crystals was among the lowest at a volume distribution of 0.00071 m3/m compared to the linear profile at 0.00191 m3/m. Optimization IV employs a dissolution strategy, which manipulates two quality specifications in one algorithm (size of crystals and number of fines), which is considered the best optimal cooling profile for seeded batch crystallization by maximizing CSD and minimizing the generation of nucleus-grown crystals.

Calcium alginate beads have been used to control release gases and volatile compounds for agricultural applications, drug delivery, waste treatment, and food product enhancement. The release rate of the gas and vapor depends on the diffusion of gas and vapor through the Ca-alginate gel matrix. However, the knowledge about the effect of process variables on the diffusion rate of gas and vapor still needs to be improved. Therefore, this study aims to investigate the effect of alginate concentration, gas release agent concentration, and bead size on the concentration of gas released from Ca-alginate beads. In this study, calcium carbonate was used as the model gas release agent, encapsulated in Ca-alginate beads to release carbon dioxide when the beads reacted with an acetic acid solution. The results showed that the concentration of carbon dioxide released by the beads depended on the bead diameter. The gas release rate was increased when the diameter of the beads was increased. The total amount of gas produced by the large beads was observed to be higher than that of small beads. Compared to small beads, large beads take longer to react completely to produce carbon dioxide gas. It was also found that the amount of carbon dioxide produced by the Ca-alginate beads was inversely proportional to alginate concentration but directly proportional to calcium carbonate concentration. The results indicated that the gas diffusion rate of the Ca-alginate beads can be tailored by adjusting the process variables of the Ca-alginate bead encapsulation process.

Ulva lactuca is a green seaweed and commonly referred to as sea lettuce and contains sulphated polysaccharides that have biological activity. Strong acids (HCl) and strong bases (NaOH) are commonly used as solvents in the conventional extraction process for ulvan, despite its lack of ecological sustainability. Deep Eutectic Solvent (DES) is an alternative to ulvan extraction solvent which is more environmentally friendly and has low toxicity. Ulvan extraction using DES with a temperature of 85-95ºC for 1 hour, and adding 2% peracetic acid pretreatment, 0.1%, 0.5%, and 2% peracetic acid posttreatment were conducted. Peracetic acid pre- and post-treatment (PAA) was carried out with a 1:10 (w/v) ratio at room temperature for 30 minutes. This study aims to optimize the use of DES in ulvan extraction with pre- and post-treatment of ulvan quality. The analysis performed included moisture content, yield, functional groups, sulphate content, and color. The test results revealed that ulvan treated with 2% PAA pretreatment had the highest moisture content and sulphate content, at 18.71% and 33.39%, respectively, while ulvan treated with 0.1% PAA posttreatment had the highest yield, at 41.96%. The addition of peracetic acid concentration can increase the color quality of the ulvan. PAA pre- and post-treatment had a significant effect on all ulvan quality parameters.

Improved absorption of rubber backbone on filler surfaces is necessary to enhance the physical properties of rubber vulcanizate. One of the ways to repair the surface of the filler is through modifying using surfactant. Hence, this study aims to compare the physical properties of natural rubber vulcanizates using clay filler and modified clay with cetyltrimethylammonium bromide (CTAB). The processes that were followed to achieve the objectives of this research were the design of rubber formulas, mastication and milling of rubber, and testing of the physical properties of rubber vulcanization. The clay characterization and its modification using FTIR and XRD were also carried out. Characterization using FTIR and XRD showed that there was indeed a clay modification with CTAB. Natural rubber compounds were also analyzed using SEM. The torque on the rheometer for modified clay with CTAB is 12.34 kg-cm higher than for original clay, which is 7.05 kg-cm. Elongation at break and tensile strength for vulcanizate using CTAB-modified clay filler is lower than that using original clay, with 300% modulus and hardness increase. Thus, clay modification using CTAB as a filler has a good effect on the curing characteristics and physical properties of natural rubber vulcanization compared to only using local clay as a filler.