Journal of Chemical Engineering and Industrial Biotechnology
The Journal of Chemical Engineering and Industrial Biotechnology (e-ISSN: 0126-8139) is an international, peer-reviewed, open-access journal published by Universiti Malaysia Pahang Al-Sultan Abdullah Press (UMPSA Press) in Kuantan, Malaysia. As a non-profit academic journal, it strives to facilitate the dissemination of scientific knowledge. It provides a strong, high-quality platform for researchers, scholars, and industry professionals worldwide to publish significant discoveries and technological advancements. The journal’s aims and scope are designed to encourage interdisciplinary collaboration and address critical contemporary challenges. The journal invites high-quality contributions in four main scientific areas: chemical engineering, environmental science, advanced materials, and industrial biotechnology. By emphasizing these related fields, the journal aims to publish cutting-edge research that supports sustainable industrial practices, promotes progress in advanced materials, and bridges the gap between fundamental laboratory research with scalable biotechnological applications. To maintain the highest standards of academic excellence, scientific integrity, and reproducibility, all submissions are subject to a thorough, unbiased, single-anonymised peer review. The journal encourages a wide variety of scholarly manuscripts to support comprehensive scientific discussion. This encompasses original full-length research articles with significant, empirically validated findings; in-depth review articles that analyse existing literature, highlight key knowledge gaps, and provide authoritative future research directions; and detailed case reports that share practical insights for the applied science community. The Journal of Chemical Engineering and Industrial Biotechnology is dedicated to promoting open scientific exchange. With the backing of UMPSA Press, it functions under an open-access publishing model. All published content is freely accessible to users and their institutions upon publication. They can read, download, copy, distribute, print, search, link to full articles, crawl for indexing, transmit data to software, or utilise the content for any lawful purpose without requiring prior permission from the publisher or authors. This policy eliminates financial, legal, and technical barriers, enhancing access to scholarly materials and aiding the global research community by boosting the visibility, reach, and impact of authors' work.
Mathematical Modelling of Rare Earth Elements Recovery by Ion Exchange Leaching from Ion Adsorption Clays
The establishment of a mathematical model for the ion exchange leaching process is key to creating a theoretical basis for the recovery of rare earth elements (REEs) from ion adsorption clay. Given the complexity of the process and limitations of experimental methods, modelling and simulation provide a promising, cost-effective approach to understanding ion exchange leaching mechanisms for REE extraction. Therefore, this study aims to develop a such a model, employing the Shrinking Core Model and utilizing MgSO4 as the leaching solution. A kinetic model was successfully developed based on the rate-determining step equation which belonged to the internal diffusion control. The calculated k value was 0.005, and the initial n value of 1.53 was later modified to 1.33 due to a deviation exceeding 10% in the Normalized Root Mean Square Error (NRMSE) value. The statistical model validation demonstrated a high level of agreement with the index values of d = 0.978, indicating an excellent agreement with experimental data, and a low value of NRMSE = 7.9 %, indicating an excellent performance model. The model consistently exhibits exponential growth in REE leaching efficiency, eventually reaching a maximum of 100% as leaching time progresses, demonstrating the leaching behaviour of REE extraction observed in this model follow the patterns observed in the leaching experiment. In conclusion, the developed kinetic model has the potential to provide reliable data on REE leaching efficiency at different leaching times across various concentrations of MgSO4solution.
Copyright (c) 2025 The Author(s) https://creativecommons.org/licenses/by-nc/4.0/
Development and Application of the Douglas-Xu Model for the Extraction of Rare Earth Elements: A Case Study of Extraction of Extraction from Saprolitic ionic Adsorption Clay
The extraction of rare earth elements is complex and resource-intensive, requiring innovative approaches to optimize technical and economic outcomes. This study introduces the Douglas-Xu model, which integrates the Douglas design methodology with Xu's counter-current principle to enhance economic evaluation and process optimization of REE separation. The model comprises five hierarchical levels—input information, operation mode, input-output structure, recycling, and separation/filtration—each incorporating economic potential analysis to ensure cost-effective design. Applied to a case study on extracting REEs from Malaysian saprolitic ionic adsorption clay for a 10,000-ton production target, the study emphasizes economic viability, process integration, and environmental considerations. The results demonstrate that the Douglas-Xu model effectively balances process optimization with economic performance, offering a comprehensive approach that addresses the limitations of existing methods. This model shows promise for improving the sustainability and profitability of REE extraction, particularly in regions outside China, where resource availability and market dynamics differ.
Copyright (c) 2026 The Author(s) https://creativecommons.org/licenses/by-nc/4.0/
Utilization of Fermented Moringa and Trichanthera Gigantea Leaves as Protein Sources in Fish Meal Production
The increasing demand for sustainable protein sources in aquaculture drives innovation in fish meal production. This study investigates the use of fermented leaves, specifically Moringa leaves and Trichanthera gigantea leaves, as alternative protein sources. The objective is to identify the optimal ratio of these fermented leaves in fish meal to enhance protein concentration. Fish feed formulations with varying ratios undergo fermentation and drying, followed by analysis of their protein, lipid, moisture, and ash content. The protein content is standardized using a Bovine Serum Albumin (BSA) calibration curve and assessed pre-fermentation via the Lowry assay. Additionally, the floatability of the fish pellets is evaluated to determine their suitability in aquatic environments. Results indicate that a formulation containing 45 w/w% Moringa leaves, 45 w/w% rice bran, and 10 w/w% starch is the most promising, with a protein content of 28.94 %, lipid content of 10.37 %, moisture content of 10.08 %, and ash content of 7 %. The conclusion emphasizes that Moringa leaves serve as a superior protein source compared to Trichanthera gigantea leaves for fish meal production, thereby supporting sustainable aquaculture practices.
Magnetic CNT Microfibrillated Cellulose of Sugarcane Bagasse (mCNT-MFCSCB) Foam as Oil Sorbent
Adsorption/absorption methods are among the popular approaches to clean oil contaminants on water surfaces due to their simplicity, efficiency, and low cost. To date, there is still ongoing research to develop oil sorbent material with high oil selectivity and, thus, high sorption capacity using environmentally friendly approaches. Herein, we proposed the development of a new oil sorbent in the form of porous carbon foam prepared from plant-based microcellulose fiber that is eco-friendly, non-toxic, reasonably cheap, and efficient, thereby promising a potential industry-adaptable approach. Three-dimension (3D) crosslinked microfibrillated cellulose of sugarcane bagasse (MFCSCB) foams were first prepared as base material, and magnetic ferrite nanoparticles (Fe3O4) and carbon nanotubes (CNTs) were further mixed into the structure of MFCSCB foam to impose hydrophobic property and introduce magnetic behavior required as a good oil sorbent material. The foam comprises a 3D interconnected structure of cellulose microfiber with high porosity embedded with CNT/Fe3O4 nanocomposite. Maximum oil sorption efficiency is achieved using Design Expert Software, where the response surface method (RSM) with a three-level, three-factor full factorial design was used. Independent factors selected in the preparation of the mCNT-MFC composite foams were the percentage of CNTs, freezing temperature, and sonication time. The sample with the highest oil sorption performance (5.05 g/g) was obtained at 0.75% CNT, -140 °C freezing time, and a sonication time of 20 min. The optimum sample was further characterized in detail using FESEM, FTIR, and XRD to understand the mechanism of oil sorption. The recyclability potential and oil sorption kinetic of the sample were also investigated. The mCNT-MFCs can selectively remove the oil from the oil/water interface with good oil sorption efficiency due to the presence of a highly porous structure and hydrophobic properties possessed by the composite, as well as easy oil recovery by a solvent removal approach.
Contemporary Advancement in Green Demulsification Technique: A Review
Emulsion has been confirmed to be a major challenge in the production and transportation of crude oil. Emulsion typically forms as soon as the well begins to produce and the water volume subsequently inclines with years of production. Corrosion of facilities, reduction of pumping efficiency of pumps, crude oil quality reduction and poisoning of refinery catalysts are some of the negative impacts of oilfield emulsion. Technological advancements have aided the incorporation of different classes of demulsification techniques to overcome the challenges imposed by emulsions. The techniques are mechanical, chemical and biological methods. The chemical method which is the most widely utilized, uses synthesized chemicals termed demulsifiers to separate emulsion components. The chemical method is posed with different forms of limitations regarding the high cost, ineffectiveness of demulsification process, unavailability of demulsifiers, negative effect on crude oil quality and environmental consequences from disposal of separated formation waters. Due to these challenges, green demulsifiers have been identified as a major alternative to the synthetic demulsifiers. Green demulsifiers, derived from plant sources, offered advantages such as biodegradability, renewability and sustainability. This review examined the current state of green demulsifiers for oil-water separation, highlighting their sources, performance, factors influencing their performances, opportunities and future challenges. The review also encompassed emulsion classes, stability and summary of other demulsification techniques. From the review, green demulsifiers showed potential for emulsion treatment in a laboratory scale with a maximum efficiency of 97.5%. Limitations such as slow separation rates, scalability and industrial application, reproducibility and variability in performance need to be addressed. Further research is necessary to investigate the environmental impact of these green demulsifier formulations. Nonetheless, green demulsifiers have the potential to enable oil companies to adopt sustainable and environmentally friendly demulsification practices if fully improved on and harnessed.
Biodegradable Saponins from Fenugreek Seeds as Eco-Friendly Wax Deposition Inhibitors in Crude Oil
Wax deposition in crude oil pipelines, caused by temperatures dropping below the wax appearance temperature (WAT), leads to paraffin build-up and blockage. While chemical inhibitors can prevent this, they are costly and harmful to the environment. This study explored biodegradable saponins extracted from fenugreek seeds as a sustainable alternative to inhibit wax deposition, improve the rheological behavior, and compare it with commercial saponins. Saponin was extracted using chemical methods, producing white crystals in samples A, B, and C at different rotational speeds (150, 200, and 250 rpm), while commercial saponin was named Sample D. Characterization using FTIR, GC-MS, and TGA confirmed the presence of saponin, with Sample C showing the closest match to the commercial version. Cold finger analysis evaluated the wax deposition reduction, with Sample C achieving the highest paraffin inhibition efficiency (PIE) of 67.13% at 20°C and 350 rpm, 51.33% at 1 h, and 90.76% at 800 ppm. Sample C emerged as the most effective inhibitor, offering a promising and biodegradable alternative to conventional wax inhibitors used in pipelines. Future research should focus on scaling up the extraction process and testing it under various pipeline conditions.
Effect of Processing Variables on Fish Oil Extraction
The accumulation of fish waste from seafood processing poses significant environmental and economic concerns. Therefore, there is a need to explore an efficient and sustainable extraction process for producing biodiesel, particularly through the extraction of fish oil rich in fatty acid methyl esters (FAME). This study investigated the effects of different processing variables, such as solvent type, temperature, and extraction time on the oil yield and FAME composition. The oil and FAME were extracted using a soxhlet extraction method. The optimal extraction conditions were ethanol, 60 °C, and 4 h, which yielded 49.0% oil yield with a high concentration of oleic acid (C18:1), ranging from 42% to 66%. These findings demonstrated that the oil extracted from fish waste has significant potential for cost-effective biodiesel production.
Innovative Use of Pineapple Peel as a Coagulant: Insights from Factorial Analysis
This study aims to optimise the preparation and application of pineapple peel coagulant to maximise turbidity reduction from simulated wastewater. The investigated factors include the drying time (0 and 24 h), settling period (0 and 24 h), coagulant dosage (1 and 2 ml), and agitation speed (10 and 50 rpm). The turbidity values were measured using the HACH Portable Turbidimeter (model 2100Q) and the viscosity values were obtained using the Brookfield Viscometer (model LV-DVII). Design Expert software designed the experimental setup and a two-level factorial design was used to analyze the data in accordance with that. Based on the analysis, the best condition to maximise turbidity reduction was suggested using 24 h dried pineapple peel and a settling period of 24 h. At this condition, the highest turbidity reduction of 71% was achieved, from 40 to 11.6 NTU. In contrast, undried pineapple peels with no settling period achieved a significant 61.69% turbidity reduction, demonstrating practical and time-efficient benefits. The p-value of 0.0003 shows that the chosen model is significant. The R2 value of 0.8795 explains the fitted model for turbidity reduction. Therefore, investigating the production of coagulants from pineapple peel waste may be an alternative method to reduce turbidity while producing a useful product.
Green microwave extraction of antioxidants and phenolic compounds from Moringa oleifera leaf: An optimization study using response surface methodology
Moringa oleifera is a good source of nutrition and very beneficial for health improvement. This study aimed to optimize the process parameters for the extraction of bioactive substances from M. oleifera leaf using microwave-assisted extraction (MAE). The Response Surface Methodology (RSM) based on Box-Behnken designs (BBD) was used to optimise the process parameters including solid-to-solvent ratio (1 to 3 g/100 mL), microwave power (100 to 200 W), and extraction time (15 to 25 min) on the total phenol content (TPC) and antioxidant activity (AA). The optimum conditions were 2.01 g/100 mL solid-to-solvent ratio, 152.7 W microwave power, and 20.54 min extraction time to obtained to obtain the optimum TPC and AA. The optimum TPC and DPPH were 529.801 mg GAE/g dry sample and 87.67%, respectively. The results were successfully fitted into the second-order polynomial model with R2 values of 0.9958 and 0.9865, respectively. The predicted TPC and AA deviate from the experimental data by 1.40% and 2.69%, respectively. Thus, the model accuracy is proved for the modelling of M. oleifera leaves extraction by MAE.
Copyright (c) 2024 The Author(s) https://creativecommons.org/licenses/by-nc/4.0/
Essential Products of Thermal Methanolic Processing of Gmelina arborea Leaves
In the quest to search for industrial raw materials from waste products, research was carried out on the thermal methanolysis of waste leaves of Gmelina arborea using barium chloride as a catalyst at 60oC reaction temperature. The products were analyzed with gas chromatography and mass spectroscopy (GC-MS). The GC-MS analysis revealed the presence of benzofuran-2-carboxaldehyde, 2,5-dimethyl 3-(H) furanone (DMHF), and 9-octadecenamide. They are significant metabolites in the food, cosmetic, and pharmaceutical industries. Their highest yields were 195.24 mg/g, 79.96 mg/g, and 364.76 mg/g constituting 4.94%, 1.95%, and 8.89% respectively in 20, 10, and 10 minutes of reaction times. The production of the metabolites would further add value to the Gbmelina arborea plantation.
Phyto-Derived Surfactants Offer Vast Promise for Optimized Hydrocarbon Extraction: A Review and Future Directions
The escalating global demand for energy, juxtaposed with the dwindling hydrocarbon reserves, necessitates the investigation of innovative recovery methodologies. A substantial fraction, roughly sixty percent, of OIP remains entrapped in reservoir rocks’ void spaces post-primary and secondary extraction. Chemical flooding constitutes a promising strategy to recuperate the residual oil. Surfactant facilitates oil recovery augmentation through IFT mitigation and modulating wettability, thereby decreasing the capillary number and improving oil mobilization. Laboratory experiments have validated the efficacy of surfactant-enhanced waterflooding, yet, the implementation of this technique in situ presents several challenges. Fortunately, botanical sources of natural surfactant offer a resource-efficient solution, boasting Inherent eco-compatibility, in stark contrast to their synthetic counterparts. Saponins, a phytochemical constituent of plants, exhibit Outstanding surficial dynamics and oil mobilization potential, rendering them a viable alternative for ameliorating energy production. This review presents a definitive and erudite analysis of the cutting-edge advancements in harnessing phyto-derived surfactants to enhance liquid hydrocarbon recovery. The analysis encompasses plant-based surfactant properties, extraction techniques, natural sources, and their role in reducing IFT and rock wettability upturn. This review highlights leaves and plant parts with saponin as reliable sources for natural surfactant extraction. Temperature, structure, salinity, and other factors impact surfactant performance. Plant-derived natural surfactants have achieved preeminent IFT reduction, contact angle optimization and substantial oil recuperation in laboratory settings. Phyto-derived surfactants in nanotechnological applications have demonstrated augmented efficacy in laboratory settings, surpassing their non-nanoparticularized counterparts. As such, Future research should explore mechanisms, scale up, and combine natural surfactant nanomaterials for optimal efficiency. This paradigm shift could revolutionize various industries, yielding innovative solutions and transformative outcomes.
Investigating the role of oxygen and residence time in the torrefaction of empty fruit bunch
This research investigates the oxidative torrefaction of Empty Fruit Bunch (EFB) as a renewable energy source. EFB samples from the LCSB palm oil mill were torrefied at 250°C with residence times (RT) of 10, 20, and 30 minutes and oxygen concentrations (OC) of 0, 5, 15, and 21%. Each experiment was repeated three times. Visual observations indicated that the EFB color darkens with increasing RT, particularly at 5% OC, where torrefaction was found to be optimal. Higher OCs of 15% and 21% led to combustion but were ineffective due to insufficient incineration. Mass yield decreased with increasing RT due to moisture and volatile loss. The torrefaction severity index (TSI) showed a linear increase in the enhancement factor with increasing TSI, while energy yield decreased as the enhancement factor exceeded mass yield. The optimal condition for torrefaction was identified as 5% OC and 30 minutes RT, balancing energy efficiency and mass retention.
Factors influencing hydrothermal pretreatment of banana peel for high recovery of pectin oligosaccharides (POS)
Utilizing banana peels creates opportunities for technological advancement in the direction of production strategies for food ingredients. Banana peel is an inexpensive by-product that can be processed into oligosaccharides with significant added value that has been reported to benefit food, animal feed and human health. Recently, pectin oligosaccharides (POS) have been the main research subject on banana peel polysaccharides. Biomass conversion from banana peel to pectin oligosaccharides has yet to be thoroughly studied. In order to fulfill the aforementioned gap, the present research study was designed to identify the best hydrothermal pretreatment conditions (temperature, pH and substrate ratio) for high recovery of POS. Prior to the pretreatment, the banana peel hydrolysate was characterized to measure the C, N, and H elements as well as the cell wall’s morphology. Next, the hydrothermal pretreatment method started by varying the temperature with three different values 105°C, 120°C, and 135°C by using an autoclave followed by pH varied at (3, 4, and 5), lastly different substrate ratio (1:5, 1:10, and 1:15 of solid: liquid ratio, w/v). After that, DNS method was chosen to determine the amount of reducing sugar i.e. POS in each sample. The study's findings suggest that the highest amount of reducing sugar POS was achieved by using UV/Vis spectroscopy at an absorbance of 540 nm were at a temperature of 135°C, pH of 5, and a substrate ratio of 1:15 (w/v). The study successfully investigated the hydrothermal pretreatment conditions of lignocellulosic biomass, specifically for banana peel to recover high POS. At 135°C, pH of 5, and a substrate ratio of 1:15 (w/v), the highest POS measured was 44.60 mg/mL.
Innovative Biomass Blending: Improving Oil Palm Trunk (OPT) Pellet Characteristics with Acacia mangium Wood for Bioenergy Production
The increasing consumption of renewable resources is mostly associated to the demand of global energy and the increase of fossil fuel prices but also to the depletion and limited availability of petroleum. The usage of these biomass has lower the environmental impact as compared with other non‐renewable fuels. Currently, pellet production from non‐woody biomass has increasing and one of the important aspects is for the sustainable use as bioenergy sources because of its quality. Due to the abundant sources of non-woody biomass materials like oil palm trunk (OPT) especially in Sarawak, its potential for pellet utilization was investigated. The pellet properties from OPT was improved by blending with fast growing species wood like Acacia mangium at different blending ratio in terms of its physical, chemical and energy properties. Both biomass in fibre forms were used for pellet production by using pelletizing machine. The properties of pellet produced were analysed to evaluate the quality of pellet in terms of its moisture content, bulk density, ash content and calorific value. Blending biomass pellet has decreased slightly the ash content from 2.1 to 2.0% and the calorific values of blending biomass pellet has increased significantly from 17.4 to 18.4 MJ/kg when 30% OPT blended with 70% A. mangium. The result obtained comparable to the standard requirements for commercial pellet that is available in the market. The characteristics of blending biomass pellet is differed from pure biomass pellets which contribute to the further improve its quality, make it has highly potential as bioenergy product.
Application of two-level full factorial design for the extraction of antioxidant activity from Decapterus Maruadsi waste by wet rendering method
Fisheries has emerged as one of the growing sectors in Malaysia. However, the fisheries sector creates considerable fish waste and directly disposed into the sea, river, sewer and onto land, resulting in environmental pollution. Fish wastes can be exploited into value-added products due to the presence of antioxidants and other bioactive components. The objective of this research is to evaluate the parameters of wet rendering method in the extraction of antioxidants from Decapterus Maruadsi waste using a two-level factorial design. The antioxidants recovery was randomized into 16 runs by Design Expert software, and its activity was determined by ABTS (2,2’-azino-bis-3-ethylbenzthiazoline-6-sulphonic acid) Radical Scavenging Assay. Then, an additional confirmation experiment was subsequently conducted by using the optimal value of the most optimum condition to verify the validity of the model developed by the Design Expert. The optimized result obtained was 58.04 mg/L with deviation of 0.08% between experimental and predicted values from Design Expert. Thus, the fish waste from Decapterus Maruadsi waste can be proposed to be used as natural antioxidant.
Effect of Nanocellulose Reinforced Recycled Paper Towards Tensile Strength
The idea of paper recycling was done due to environmental issue. However, the properties of recycled paper like tensile will decrease each time it is recycled. Addition of reinforcing filler may increase the properties of recycled paper. Thus, in this research, nanocellulose was used as reinforcing filler in recycled paper. The objectives of this research are to fabricate papers from recycled paper and to investigate the effect of different nanocellulose and pressure of compression molding in paper fabrication towards tensile strength of recycled paper. Two types of nanocellulose used were commercialized cellulose nanofiber (CNF) and cellulose nanocrystals (CNC). CNC from filter paper and empty fruit bunches (EFB) were isolated via acid hydrolysis. The recycled paper was fabricated using traditional me. thods (net) and further processed with compression molding. All samples with nanocellulose increase in tensile strength. The tensile strength recorded 114% improvement at 15.28 N/mm2 with 5wt% of CNF.
Optimization of Starter Bokashi Bran From Expired Mushroom Blocks Using Central Composite Design
Mushroom production as the largest solid-state fermentation industry globally. It draws attention to a significant economic and environmental challenge, specifically the storage and disposal of expired mushroom blocks (EMBs) remaining after harvest. Importance of ongoing biotechnological research focused on fungi utilizing various agro-industrial wastes to produce biofertilizer for industrial. The paper proposes using EMBs as a substrate for Bokashi fermentation as fertilizer, focusing on the development of starter Bokashi Bran. The study identifies and optimize bacterial and fungal growth in Bokashi Fermentation using ADA starter Bokashi bran sample from ADA Fresh Farm, Johor Bharu using Response Surface Methodology (RSM). Factors affecting growth both microbes were analysed: EMB content (2 g/ml to 10 g/ml) and fermentation durations (5 days to 9 days). The analysis analysed the highest bacterial and fungal growth in Starter Bokashi Bran using the Design Experts (DE) software Version 7.0 predicting maximum growth at 8 days and 4g/ml respectively. The quadratic model showed a good fit, with an R-squared value exceeding 0.80 and a confidence level surpassing 95%.The research demonstrated that EMBs can be utilized as alternative medium for starter bokashi bran that are eco-friendly and sustainable biofertilizer.
Phytochemical and pharmacological activities of Commiphora gileadensis: A review
Background: Commiphora gileadensis is an important medicinal plant with a variety of uses in medicine. Secondary phytoconstituents of the plant are medicinally important through their pharmacological actions, which include antioxidant, antibacterial, cytotoxic, anti-cancer, and antiviral properties. Objective: The aim of this review is to identify the phytochemical, pharmacological, and toxicological properties of the C. gileadensis. Method: The study’s review methodology is based on a thorough search of the literature, with data drawn from book chapters, research articles, review articles, and conference papers. Results: According to the findings, pharmacological studies support the use of C. gileadensis extracts in folk medicine, where the phytochemical research revealed that this plant is high in saponins, flavonoids, proteins, triterpenes, lipids, sterols, fibers, amino acids. Conclusion: As a result, this review presented an overview of C. gileadensis’ bioactive components, phytochemical and pharmacological capabilities, as well as its toxicity. The review suggests that more attention be paid to the stem, bark, and leaf of C. gileadensis because extending research materials could lead to the discovery of novel bioactive components.
Sustainable Materials in Concrete Railway Sleepers: A Review of Current Developments and Future Prospects
Concretes have been the favoured material to make concrete railway sleepers due to better accessibility and weather compared to their timber counterparts. Railway sleepers are crucial infrastructure and 5% of concrete sleepers fail prematurely. Sleeper failure could result in catastrophic railway accidents. Hence, improvement is needed in the concrete sleeper mixes. Previous literature has identified two methods of improving concrete strength in concrete mixes with wastes, through replacement of concrete constituents or the use of alkali-activated materials. Use of wastes as partial concrete material replacements reduces the volume of concrete materials while alkali-activated material forms a concrete-like compound that eliminates the use of cement. These methods improve the strength performance and sustainability aspects of the concrete. While many studies have been conducted on these two types of sustainable concrete, their application in concrete railway sleepers has not been investigated. Thus, this paper looks to review the two different types of sustainable concretes through some previous literature that has been conducted on its application in concrete railway sleepers as well as those that have yet to be studied. Ultimately, identifying the best sustainable materials for concrete railway sleepers.
Parametric Factorial Analysis of Fermentation Conditions for Protease Production from Pineapple Waste
Pineapple waste is abundant in cellulose, hemicellulose, lignin, complex carbohydrates, and protein. One simple way to use pineapple waste as a substrate is to utilize it with the probiotic beverage to produce enzymes through submerged fermentation. Studies on fermentation using pineapple waste have mainly focused on cellulose, xylanase, and pectinase, with little information on protease fermentation. Future studies on pineapple waste-based protease fermentation should be conducted. The present work aims to investigate the significant process parameters affecting protease fermentation from pineapple waste. The parametric screening was performed using the two-level fractional factorial design by Design Expert 7.1.6. In this work, four process parameters were manipulated for protease fermentation which is incubation time from 24 hours to 72 hours, temperature from 20.0 °C to 40.0 °C, substrate concentration from 10.0 % to 30.0 % and pH value from 4.0 to 8.0. The result showed that the most significant process parameters affecting protease fermentation were temperature, pH value and incubation time. This study investigated that the highest protease activity, 0.118 U/mL can be obtained with 48 hours of incubation time, 30.0 °C of temperature, 20.0 % of substrate concentration and pH 6.0.
Effect of Process Parameters on Immobilization of Recombinant Escherichia coli on Coconut Fiber
Escherichia coli (E. coli) is the earliest and most widely used host to produce recombinant proteins, one such example being cyclodextrin glucanotransferase (CGTase) which has found application in numerous industries such as food, environmental engineering and pharmaceutical. The recombinant protein in E. coli was applied to overcome the low output of CGTase from Bacillus species such as Bacillus lehensis and Bacillus licheniformis. However, cell lysis and plasmid instability have been some of the stumbling blocks during the production of recombinant protein in E. coli. Therefore, cell immobilization has been proposed as a way to increase CGTase production while maintaining high cell stability. The objective of this study is to immobilize recombinant E. coli on coconut fiber. The effect of the process parameters, namely pH level (5, 6, 7, 8, and 9), contact time (12, 15, 18, 21, 24, and 27 hours), and temperature (20, 25, 30, 35, and 40 °C), towards the immobilization of recombinant E. coli onto coconut fiber was studied. The optimal pH resulted in the highest immobilization yield was pH 8 (58.90%). The best contact time for the highest immobilization yield (57.59%) was 24 hours. The optimum temperature was identified at 25 °C with immobilization yield of 58.78%. Hence, the optimum conditions could improve the immobilization of recombinant E. coli on the carrier and the coconut fibre was an appropriate carrier material for cell immobilization process for the high CGTase production with high cell stability.
Mechanical, thermal, and morphological properties of poly(lactic acid) (PLA)/ recycled tyre rubber waste compatibilised with chain extender
The accumulation of waste tires in our society is a pressing issue due to their short lifespan and increasing demand. This research delves into effective methods for recycling waste tires, with a particular focus on utilising biopolymers. Polylactic acid (PLA), a completely biodegradable polymer, has gained popularity for its biocompatibility, biodegradability, mechanical strength, and ease of processing. To overcome its toughness and thermal stability limitations, PLA has been blended with commercial polymers, such as rubber. Furthermore, the addition of 10% recycled tyre waste to 90% PLA has been shown to increase its durability and strength. Joncryl® ADR is used as a chain extender and reactive compatibiliser to enhance the chemical interactions in the binary blend. The samples were prepared using a twin-screw extruder with the temperature between 150 and 190 ºC and 60 rpm of screw speed. These blends are then analyzed using a range of characterization techniques, including Fourier transform infrared (FTIR) spectroscopy, differential scanning calorimetry (DSC), scanning electron microscopy (SEM), tensile testing, and notched Izod impact testing. The blends were then characterized by chemical changes, thermal transitions, and thermal degradation. It was found that the 90/10/0.6 (PLA/RW/ADR) nanocomposite exhibited maximum thermal degradation.
Copyright (c) 2023 The Author(s) https://creativecommons.org/licenses/by-nc/4.0/
Optimization of Solvent Systems for Color Fractionation of Monascus Pigment
Monascus fungi are unique among the various microorganisms that produce edible pigments, which consist of red, orange, and yellow. These pigments are typically present in a mixture. Hence, pigment separation is needed. This study aims to optimize solvent systems that can effectively fractionate the pigments. The optimization was carried out using column chromatography and the data was analyzed using Central Composite Design (CCD). The interaction of the solvent systems ethyl acetate : formic acid : acetic acid : water was optimized. The optimal solvent system obtained was 98 : 14 : 12 : 28 (vol/vol.) for ethyl acetate : formic acid : acetic acid : water, respectively. The red and yellow pigment obtained were 2.42 mg and 0.93 mg, respectively. Based on the finding, 72.2% of the total Monascus pigments was red while remaining was yellow.
Molecular Dynamics Simulation Study of the Diffusion of Carbon Dioxide in Heptane: Application in Natural Gas Cleaning
Using solvents to remove carbon dioxide is an effective way to purify natural gas. Diffusion of solute in solvent is key to natural gas purification. In this study, molecular dynamics (MD) simulations of the diffusion of carbon dioxide in heptane at different temperatures and pressures were performed to simulate the conditions of industrial purification process. The diffusion coefficients were measured in two different configurations: pure solvent and binary solute-solvent systems. The diffusion coefficients of the binary system were observed to be in the order of 10-9 m2/s. An increased temperature was observed to increase the diffusion coefficient of the carbon dioxide in heptane while an increase in pressure reduced the value of the diffusion coefficient. The diffusion coefficient was also observed to follow an Arrhenius-type relationship with respect to temperature. The activation energy of the system increased from 9.228 kJ/mol to 11.139 kJ/mol with pressure increase. A linear relationship was detected between the diffusion coefficient and the viscosity of the system and an increased viscosity of the system results in a decreased diffusion coefficient. The results of the research showed that carbon dioxide behavior in heptane offers the theoretical backing for the development of a new natural gas desulphurization solvent.
Aging Dynamics of Bio-Coagulants: Implications for Oily Wastewater Treatment Efficiency
Inadequate treatment of oily wastewater discharge can contribute to an increase in the levels of both biological oxygen demand (BOD) and chemical oxygen demand (COD) in the water. Various studies have highlighted the effectiveness of natural bio-coagulants in particular chitosan as an alternative to the chemical coagulants available in the market. However, minute studies have been reported in discussing the correlation between the aging effect of the bio-coagulant and its performance. Thus, this paper presents research on the aging effect of bio-coagulants for treating oily wastewater. In this study, G-Treat was used as the bio-coagulant, which was produced from chitosan powder, acetic acid, and deionized water. The experimental procedure started by filling 500 mL of oily wastewater into a beaker. Next, 10 wt. % of G-Treat was added into the beaker for the jar test, which was mixed for 30 min at 150 rpm, followed by 2 hours settling time. Then, the mixture was separated using filter paper. The analysis of oily wastewater characteristics was conducted using five types of analyses, which are pH, chemical oxygen demand (COD), biological oxygen demand (BOD), total suspended solids (TSS), and oil and grease (O&G) under the parameters of days (0–7 days), weeks (0–6 weeks), and months (0–3 months). From the result, the best performance of G-Treat was achieved at the optimum parameters during week 2, with 33.16%, 65.75%, 35.73%, 28.58%, and 0% removal of pH, COD, BOD, TSS, and O&G, respectively. In conclusion, the studied bio-coagulant demonstrated higher removal of pH, COD, BOD, TSS, and O&G at optimum parameters, and eventually, the level of effectiveness will drop.
Effect of Custard Apple (Annona squamosa L.) Seeds Extracts on In-Vitro Activity of Malassezia globosa
Scalp is unique among skin areas in humans. It is characterized by a thick skin layer with high follocular density and sebaceaous glands. The presence of these glands along the dark and warm environment of the scalp makes it more prone to mycotic infections like dandruff. This research was aimed to ascertain the potential of custard apple seed phytoconstituents on dandruff causing Malassezia globosa. The alkaloid, flovonoid, saponin and tannin extracts were not effective on M. globosa. However, glycoside extract was more effective than the crude extract. Glycoside extract had inhibition zones of 35±0.3, 20±0.5, 14±0.2 and 12±1mm at 100, 50, 25 and 12.5mg/ml respectively while crude had zones of 15±0.4, 12±0.2, 10±0.1 and 0±0mm at 100, 50, 25 and 12.5mg/ml respectively. This study suggests the glycoside extract of custard apple seed could offer potential therapeutic benefits in the treatment of dandruff due to its fungicidal properties.
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Ferromagnetic Enhancement of Microcrystalline Cellulose via Chemical Reduction Method
Iron oxide nanoparticles (NPs) have potential in biological, biomedical, and environmental applications because of their characteristics such as magnetic susceptibility, stability and biocompatibility. However, it also has limitation, such as aggregation of magnetic NP. As a result, coating materials should be used to modify the particles’ outer surface. In this paper, we focused on the synthesis of iron oxide by chemical reduction method and coating it with Fe(III) nitrate, polyvinylpyrrolidone (PVP) and hydrazine. In order to determine effective and economical usage conditions, the coating solution at two different concentrations were prepared. The effect of coating iron oxide with microcrystalline cellulose (MCC) was prepared at different concentrations of iron (III) nitrate on the nanomaterials with respect to morphological, thermal, magnetic susceptibility. A good morphology images of FeNp-MCC were proved by Scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Energy dispersive X-ray (EDX) spectra reveals the presence of carbon, oxygen and iron in the synthesized microparticles. TGA analysis showed iron material was successfully formed into the surface of MCC. Lastly, the magnetism results proved that cellulose is strongly interacting with magnetite nanoparticles.
Facile Synthetical Method of Squalene from Vegetable Residue
The proscription of the use of shark liver oil for the production of squalene by the International Ocean Conservation and Advocacy Organization (IOCAO) for the protection of sharks in 2005, leads to a great reduction in its quantity in circulation. The quantity in circulation is not enough to meet its growing demand. Therefore, the research for the synthesis of squalene was extended to the use of Gmelina arborea leaves. This was carried out by treating the dry leaves of Gmelina arborea with methanol and a barium chloride catalyst at 90 °C at varying reaction times in minutes. The products were analyzed using gas chromatography and mass spectrometry (GC-MS). The GC-MS revealed the following results; 162.39, 171.98, 145.69, 92.43, 108.32 and 118.83 mg/g for the reaction times of 10, 20, 30, 40, 50 and 60 minutes, respectively. The maximum yield achieved was 171.98 mg/g at a reaction time of 20 minutes and the minimum yield was 92.43 mg/g at a time of 40 minutes. This method is fast, safe, cost-efficient and economically viable for squalene production. Hence, Gmelina arborea has the potential for squalene production to meet up with the global demand.
THE EFFECT OF BLENDING RATIO ON BIODIESEL PROPERTIES, EMISSIONS AND ENGINE PERFORMANCE
This work presents the effects of biodiesel blending on its properties, emissions, and performance. The rubber seed oil (RSO) and waste cooking oil (WCO)-based biodiesel were prepared using a transesterification method in the presence of a heterogeneous catalyst. Several formulations were derived from two types of biodiesels (RSO and WCO) and tested according to the ASTM D6751 specification for acid value, free fatty acid (FFA), kinematic viscosity, pour point, cloud point, density, and calorific value. For the WCO-based biodiesel, the best blend was WCO B5, with properties closely matching those of petrodiesel. Significantly, the formulations with higher WCO content (e.g., B10 and above) suffered from serious drops (above 8%) in calorific value. In contrast, the RSO diesel blend showed less than 5% drops in calorific value for formulations up to a 20% biodiesel blend (B20). In addition, an indiscernible difference was obtained between the WCO B5, RSO B5, and petrodiesel in terms of engine power, torque, and CO2 emissions, although the RSO B5 did produce less NOx (158 ppm) than both the WCO B5 (390 ppm) and the petrodiesel (220 ppm). The results showed that blending of WCO and RSO with petrodiesel up to 10%, i.e., B10, is practically applicable for diesel cars with power reduction less than 10%.
Fabrication and Characterization of Semi-refined Carrageenan Films Incorporated with TiO2 Nanoparticles
In this study, a packaging film was developed using semi-refined carrageenan, incorporating varying concentrations of TiO2 nanoparticles. The aim of this study was to investigate the effect of TiO2 nanoparticles on the properties of the SRC-based film. The films were prepared through a casting method, and the resulting samples were characterized in terms of their functional, mechanical, and physical properties. The SRC film containing 1 wt% of TiO2 nanoparticles demonstrated the highest tensile strength. However, with the addition of TiO2 nanoparticles at any concentrations (1, 3, 5, and 7 wt%), the elongation at break of the SRC film decreased in comparison to the SRC film without TiO2 nanoparticles. Moreover, as the concentration of TiO2 nanoparticles increased from 1 to 7 wt%, the moisture content, and water solubility of the SRC films decreased. The FTIR spectra analysis provided valuable information on the interaction between SRC and TiO2 nanoparticles. The results suggest that incorporating TiO2 nanoparticles into semi-refined carrageenan films shows promise for developing packaging materials with improved mechanical strength and physical performance.