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Abstract Highly functional and robust biobased materials are still in research to produce valuable composites for various applications. The literature shows the gap of new raw biobased materials in market which can functionally tuned and structurally modified for development of 2d/3d architectures. Thus, in the present study, very cheap, easily available agricultural waste, pineapple leaf fiber (PL-raw) was used for the isolation of microcrystalline cellulose (PL-MCC) and further functionalized using upscaled chemical approach to carboxymethyl microcrystalline cellulose (PL-CMMCC). Very advanced techniques like Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDX), X-ray diffraction analysis (XRD), and differential scanning calorimetry (DSC) served to characterize the raw material, high crystalline PL-MCC, and modified carboxy methyl MCC. FTIR determined presence of different absorbed peak at approximately 1620.2 cm−1, and at 1423.8 cm−1, carboxyl groups were assigned to PL-CMMCC. On the other hand, the XRD findings verified that PL-CMMCC’s crystalline structure has decreased. Analysis by SEM revealed a damaged surface morphology for PL-CMMCC. Following chemical treatments, the EDX analysis revealed that each fiber sample contained a highly pure cellulose elemental composition. Thus, results explain the utilization of agricultural waste, pineapple leaf fiber to high valuable products like highly crystalline PL-MCC, in addition further modification of PL-MCC could leads to formation of highly functional material that could be used for other applications too in future.

Abstract This study presents a novel method for nanocellulose production using [Bmim]Cl as a green solvent, with enhanced hydrolysis efficiency achieved through the addition of a transition metal complex as a catalyst. The redox capability of the transition metal complex to break the glycosidic bonds in cellulose is amplified by the addition of an oxidizing agent. This protocol represents the latest innovation in the field of nanocellulose production, resulting in improved yield and reduced particle size. Nanocellulose (NC) was extracted from date seeds using 1-butyl-3-methylimidazolium chloride [Bmim]Cl coupled with a transition metal complex comprising copper metal and pyridine as a ligand along with $${\text{H}}_{2}{\text{O}}_{2}$$ H 2 O 2 as an oxidizing agent. Unlike conventional [Bmim]Cl hydrolysis, which typically yields only microcrystalline cellulose (MCC), this approach resulted in a 25% higher yield of NC than that of MCC. Dynamic light scattering analysis showed a substantial reduction in hydrodiameter from 1200 nm for MCC to 128.7 nm for NC, highlighting the remarkable efficiency of this process. Thermal analysis demonstrated the high stability of NC, which showed a $${T}_{onset}$$ T onset of 286 °C and an activation energy ( $${E}_{a}$$ E a ) of 220.41 kJ/mol. X-ray diffraction analysis indicated that NC possessed a high degree of crystallinity ( $${C}_{rl}=$$ C rl = 70.28%). Furthermore, NC underwent modification with 3-aminopropyltriethoxysilane to replace free hydroxyl groups (–OH), making it redispersal and suitable for various applications. This modification was confirmed through Fourier transform infrared spectroscopy, which showed the presence of characteristic functional groups, and energy-dispersive X-ray spectroscopy, which verified the elemental composition. Zeta potential measurements revealed surface charge differences, with MCC at − 27.87 mV, NC at − 27.28 mV, and modified NC at − 44.72 mV, indicating improved colloidal stability after modification. These findings highlight the protocol's effectiveness and its potential impact on the NC production industry, offering improved yields and the production of nanosized fibers using green solvents.

Abstract Background This study utilized ultrasonication-assisted green extraction techniques to explore the physicochemical, rheological, biological, and prebiotic properties, alongside gut modulation abilities of novel polysaccharides extracted from date pomace. The extraction aimed at enhancing the utilization of date pomace, a by-product of date fruit processing, by investigating its potential as a functional food ingredient. The research focused on optimizing the extraction process, understanding the complex structure of the polysaccharides, and assessing their various health-related functionalities. Results The ultrasonically extracted polysaccharides (UPS) were identified as a mixture of significant bioactive compounds including galacturonic acid, galactose, glucose, arabinose, and fructose, showcasing a high molecular weight of 537.7 kDa. The study found that UPS exhibited outstanding antioxidant activities, with scavenging abilities ranging from 59 to 82% at a concentration of 1000 mg/L. Additionally, UPS demonstrated potent inhibitory effects on α-amylase (83%), α-glucosidase (81%), and ACE-inhibition (45%), alongside strong antiproliferative activities against Caco-2 and MCF-7 cancer cell lines and broad-spectrum antimicrobial properties. Remarkably, UPS also enhanced the abundance of beneficial gut microbiota, including Actinobacteria, Firmicutes, and Proteobacteria, during in vitro fermentations and positively modulated gut metabolic pathways, promoting the production of major short-chain fatty acids. UPS had higher abundance in pathways related to cofactors, vitamins, electron carriers, and prosthetic groups biosynthesis compared to blank. Conclusions The findings affirm the potential of UPS extracted from date pomace as an innovative and promising functional food ingredient. Its high molecular weight, complex sugar composition, significant antioxidant, antimicrobial, antiproliferative activities, and prebiotic properties make it a valuable resource for promoting health and managing diseases. This study paves the way for further research on the bioavailability and physiological effects of UPS in vivo, highlighting the importance of sustainable utilization of agricultural by-products in developing functional foods that support human health. Graphical Abstract

This review aims to comprehensively consolidate the knowledge and understanding of the development of thermal insulation materials for buildings using lignocellulosic waste materials. The building sector currently accounts for approximately 40 % of global energy consumption. Lignocellulosic waste materials are abundantly available worldwide, with their effective repurposing imperative to achieve positive environmental impacts. Lignocellulosic waste can be directly employed as a thermal insulator with minor modifications and binders. These materials consistently exhibit thermal conductivities below 0.1 W/m.K, the defining criterion for effective thermal insulation. An alternative strategy involves incorporating lignocellulosic waste as a filler or reinforcement agent within thermoplastics and thermosets to enhance their physicochemical attributes and render them suitable as thermal insulators. This approach aligns with sustainability principles and enables the replacement of 30–50 % of the polymer content with renewable material, with the resultant thermal conductivity values in these investigations also below 0.1 W/m.K. Moreover, with interest centered on the integration of lignocellulosic waste into the modification of biodegradable polymers to produce thermal insulation materials, prospects are promising for utilizing treated lignocellulose, cellulose, and their derivatives (such as nanocellulose and microcrystalline cellulose) as economical materials for developing biodegradable insulators. This review presents a thorough analysis and comparison of these approaches, providing researchers with insights for designing future research methodologies and addressing existing gaps in knowledge.

This work investigated the effect of hybridization of flax fabric (FF) with carbon/Kevlar fabric (CK) on the flexural, dynamic mechanical analysis and high velocity impact. Hand lay-up technique was used to fabricated different ratio of flax to carbon/Kevlar hybrid composites, which were hot-pressed and then cured. It was revealed that increase in ratio of CK has improved the flexural properties, storage modulus, loss modulus, energy absorption and ballistic limit of the composites. Interestingly, hybrid composite with ratio 25:75(FF:CK) has highest flexural properties, storage modulus and loss modulus among the other composites. The cole-cole plot and damping factor reveals that hybrid composite with ratio 25:75(FF:CK) has the strongest fibre/matrix adhesion. The hybrid composite with ratio 25:75 (FF:CK) displayed the highest Tg. Based on high velocity impact test, it was shown that there is not much different in energy absorption and ballistic of the hybrid composites compared to plain CK composite. FF/CK hybrid composites have the potential to be used in high performance application such as ballistic helmet.

The rising liability to suffer the environment eco-friendly covers the approach to the improvement of materials with bio-natural wastes. This research experimentally aims to study bamboo/oil palm reinforced bio-epoxy hybrid composite. Bamboo (B) and oil palm (O) reinforced bio-epoxy was fabricated as a control. The fabricated biocomposites were characterised by mechanical properties (tensile tests), physical characterisations (density, water absorption (WA) and thickness swelling (TS)), thermomechanical analysis (TMA), and morphological (scanning electron microscopy (SEM)). Among the hybrid composites, 5B5O has the highest tensile strength and modulus which is 35.66 MPa and 4.95 GPa, respectively. Based on the findings, the physical properties, WA and TS capacities (WA and TS) of B and 3B7O biocomposites were increased compared with all corresponding biocomposites while the O biocomposite exhibited lower TS and WA values compared to other samples. The hybrid 3B7O biocomposite sample was attributed to a higher void percentage (6.29%) and lower density (1.25 g/cm3) compared to other biocomposites. Generally, the SEM analysis of hybrid biocomposites confirms a valuable interaction between the filler and the matrix as further penetration for the matrix was permitted into the greatly porous structures of natural fibres. Furthermore, the SEM test of the fracture point confirmed the observations from the mechanical properties. The obtained findings confirmed that hybrid fibres improve the properties of the bio-epoxy matrix and can be utilised as sustainable and renewable biocomposites for several applications such as automotive tools, furniture and medical tools.

ABSTRACT: Making cheese from camel milk (CM) presents various challenges due to its different physicochemical properties compared with bovine milk (BM). In this study, we investigated the chemical composition, proteolysis, meltability, oiling off, texture profile, color, microstructure, and rheological properties of low-fat Cheddar cheese (LFCC) prepared from BM–CM blends. LFCC was produced from BM or BM supplemented with 15% CM (CM15) and 30% CM (CM30), and analyzed after 14, 60, 120, and 180 d of ripening at 8°C. Except for salt content, no significant differences were observed among LFCC from BM, CM15, and CM30. The addition of CM increased the meltability and oiling off in the resulting cheese throughout storage. With respect to color properties, after melting, LFCC CM30 showed lower L* values than LFCC made from BM and CM15, and a* and b* values were higher than those of BM and CM15 samples. LFCC from CM30 also exhibited lower hardness compared with the other cheeses. Moreover, LFCC made from BM showed a rough granular surface, but cheese samples made from BM–CM blends exhibited a smooth surface. The rheological parameters, including storage modulus, loss modulus, and loss tangent, varied among cheese treatments. The determined acetoin and short-chain volatile acids (C2–C6) in LFCC were affected by the use of CM, because CM15 showed significantly higher amounts than BM and CM30, respectively. The detailed interactions between BM and CM in the cheese matrix should be further investigated.

Abstract Extraction of lignin via green methods is a crucial step in promoting the bioconversion of lignocellulosic biomasses. In the present study, utilisation of natural deep eutectic solvent for the pretreatment of kenaf fibres biomass is performed. Furthermore, extracted lignin from natural deep eutectic solvent pretreated kenaf biomass was carried out and its comparative study with commercial lignin was studied. The extracted lignin was characterized and investigated through Infrared Fourier transform spectroscopy, X-ray Diffraction, thermogravimetric analysis, UV–Vis spectroscopy, and scanning electron microscopy. FTIR Spectra shows that all samples have almost same set of absorption bands with slight difference in frequencies. CHNS analysis of natural deep eutectic solvent pretreated kenaf fibre showed a slight increase in carbon % from 42.36 to 43.17% and an increase in nitrogen % from − 0.0939 to − 0.1377%. Morphological analysis of commercial lignin shows irregular/uneven surfaces whereas natural deep eutectic solvent extracted lignin shows smooth and wavy surface. EDX analysis indicated noticeable peaks for oxygen and carbon elements which are present in lignocellulosic biomass. Thermal properties showed that lignin is constant at higher temperatures due to more branching and production of extremely condensed aromatic structures. In UV–VIS spectroscopy, commercial lignin shows slightly broad peak between 300 and 400 nm due to presence of carbonyl bond whereas, natural deep eutectic solvent extracted lignin does not show up any peak in this range. XRD results showed that the crystallinity index percentage for kenaf and natural deep eutectic solvent treated kenaf was 70.33 and 69.5% respectively. Therefore, these innovative solvents will undoubtedly have significant impact on the development of clean, green, and sustainable products for biocatalysts, extraction, electrochemistry, adsorption applications.

Polymer mortars have attracted immense interest as effective and rapid repair materials in the modern construction industry owing to their advantages over conventional Portland cement mortar. Various types of polymer binders, such as unsaturated polyester resin (UPR), have been used in polymer mortar owing to their low cost, excellent strength, high workability, and rapid curing. However, the brittleness of Unsaturated polyester resin mortar (UPRM) limits its applications in construction. Herein, we investigated the feasibility of reutilizing locally available industrial crumb rubber (CR) (CR,

Natural deep eutectic solvent (NADES) composed of choline chloride and formic acid was used to fractionate date waste into lignin and cellulose streams. NADES treatment increased the cellulose content from 44 wt% in raw waste (RW) to 72 wt% in extracted cellulose fibers (CFs). Scanning electron microscopy revealed needle-like fibers, underlining the effectiveness of NADES treatment in removing non-cellulosic components. Additionally, the CFs exhibited improved thermal stability, with an initial decomposition temperature (Tonset) of 265 °C. Kinetic analysis revealed a higher activation energy (Ea) of 100.90 kJ/mol for CFs than 63.10 kJ/mol for RW, indicating higher thermal stability due to enhanced cellulose content. Pyrolysis coupled with gas chromatography/mass spectroscopy analyses of CFs showed a lower release of nitrogen compounds and a higher content of hydrocarbons and cyclic ethers, all of which are beneficial for bio-oil production. Overall, the findings of this study will promote the use of NADES as an inexpensive, nontoxic, and recyclable solvent to advance the field of selective pyrolysis.

The aim of this study was to assess the effects of ultrafiltration (UF) combined with high-pressure processing (HPP) or heat treatment on the quality of yogurts produced from camel milk (CM) or bovine milk (BM). Milk was concentrated by UF (0, 1, and 2-fold) before applying heat (75 °C or 85 °C for 30 min) or HPP (350 MPa or 550 MPa for 5 min). Yogurts were produced using starter cultures (Streptococcus thermophilus and Lactobacillus bulgaricus subsp. delbrückii) and pH, viscoelastic and thixotropic rheological properties, and protein profiles were determined. Compared to HPP, heat-treated yogurts, especially at 85 °C, exhibited the highest rheological storage and loss moduli signifying stronger gels. Lower storage modulus values in HPP treated CM yogurts were explained by the lack of long-range β-lactoglobulin bridges at micelle surfaces and the reassociation of pressure-dissociated caseins by hydrophobic interactions. Percent structural regeneration, which increased with increasing milk concentration, revealed higher thixotropic behavior in the case of heat- than in HPP-treated samples. SDS-PAGE electrophoresis revealed extensive proteolysis in CM compared to BM yogurts suggesting the involvement of some enzyme activities in the low gel strength.

Polysaccharides are abundant macromolecules. The study extracted date seed polysaccharides (UPS) using ultrasound-assisted deep eutectic solvent extraction to valorize date seeds. UPS were subjected to comprehensive characterization and evaluation of their bioactivity, prebiotic properties, and their potential to modulate the gut microbiome. Characterization revealed UPS's heteropolysaccharide composition with galactose, mannose, fructose, glucose, and galacturonic acid respectively in 66.1, 13.3, 9.9, 5.4, and 5.1%. UPS showed a concentration-dependent increase of radical scavenging and antioxidant activities, evidenced by FRAP, TAC, and RP assays. They also displayed antimicrobial efficacy against E. coli O157:H7, S. typhimurium, S. aureus, and L. monocytogenes. Rheological analysis showed UPS's elastic-dominant nature with thixotropic tendencies. UPS inhibited α-glycosidase, α-amylase, and ACE up to 86%, and reduced Caco-2 and MCF-7 cell viability by 70% and 46%, respectively. UPS favored beneficial gut microbiota growth, releasing significant SCFAs during fecal fermentation.

Date palm pit (DPP)-filled poly (-hydroxybutyrate) (PHB) composites were prepared, evaluated, and characterized to determine their thermal insulation ability. Thermal conductivity values ranged between 0.086 and 0.100 W/(m·K). At a maximum filler concentration (50% (w)), the specific heat capacity and thermal diffusivity were 1 183 J/(kg·K) and 0.068 9 mm2/s, respectively. The DPP increased the thermal stability, and the highest compressive strength obtained was 80 MPa at 30% filler content. The PHB-DPP composites exhibited promising water absorption (less than 6%) and tensile strength (6–14 MPa). Date-pit-based PHB composites could be used in sustainable building engineering and cleaner production.

ABSTRACT: The manufacture of camel milk (CM) yogurt has been associated with several challenges, such as the weak structure and watery texture, thereby decreasing its acceptability. Therefore, this study aimed to investigate the effect of whey protein isolate (WPI) addition on the health-promoting benefits, texture profile, and rheological properties of CM yogurt after 1 and 15 d of storage. Yogurt was prepared from CM supplemented with 0, 3, and 5% of WPI and compared with bovine milk yogurt. The results show that the water holding capacity was affected by WPI addition representing 31.3%, 56.8%, 64.7%, and 45.1% for yogurt from CM containing 0, 3 or 5% WPI, and bovine milk yogurt, respectively, after 15 d. The addition of WPI increased yogurt hardness, adhesiveness, and decreased the resilience. CM yogurt without WPI showed lower apparent viscosity, storage modulus, and loss modulus values compared with other samples. The supplementation of CM with WPI improved the rheological properties of the obtained yogurt. Furthermore, the antioxidant activities of yogurt before and after in vitro digestion varied among yogurt treatments, which significantly increased after digestion except the superoxide anion scavenging and lipid oxidation inhibition. After in vitro digestion at d 1, the superoxide anion scavenging of the 4 yogurt treatments respectively decreased from 83.7%, 83.0%, 79.1%, and 87.4% to 36.7%, 38.3%, 44.6%, and 41.3%. The inhibition of α-amylase and α-glucosidase, angiotensin-converting enzyme inhibition, cholesterol removal, and degree of hydrolysis exhibited different values before and after in vitro digestion.

Abstract Exopolysaccharides (EPSs) possess distinctive rheological and physicochemical properties and innovative functionality. This study aimed to investigate the physicochemical, bioactive, and rheological properties of an EPS secreted by Lactococcus lactis subsp. lactis C15. EPS-C15 was found to have an average molecular weight of 8.8 × 105 Da and was identified as a hetero-EPS composed of arabinose, xylose, mannose, and glucose with a molar ratio of 2.0:2.7:1.0:21.3, respectively. The particle size and zeta potential represented 311.2 nm and − 12.44 mV, respectively. FITR exhibited that EPS-C15 possessed a typical polysaccharide structure. NMR displayed that EPS-C15 structure is → 3)α-d-Glcvi (1 → 3)α-d-Xylv (1 → 6)α-d-Glciv(1 → 4)α-d-Glc(1 → 3)β-d-Man(1 → 2)α-d-Glci(1 → . EPS-C15 scavenged DPPH and ABTS free radicals with 50.3% and 46.4% capacities, respectively. Results show that the antiproliferative activities of EPS-C15 revealed inhibitions of 49.7% and 88.1% against MCF-7 and Caco-2 cells, respectively. EPS-C15 has antibacterial properties that inhibited Staphylococcus aureus (29.45%), Salmonella typhimurium (29.83%), Listeria monocytogenes (30.33%), and E. coli O157:H7 (33.57%). The viscosity of EPS-C15 decreased as the shear rate increased. The rheological properties of the EPS-C15 were affected by changes in pH levels and the addition of salts. EPS-C15 is a promising biomaterial that has potential applications in various industries, such as food, pharmaceuticals, and healthcare.

ABSTRACT: During fermentation, camel milk forms a fragile, acid-induced gel, which is less stable compared with the gel formed by bovine milk. In this study, camel milk was supplemented with different levels of soy extract, and the obtained blends were fermented with 2 different starter culture strains (a high acidic culture and a low acidic culture). The camel milk-soy extract yogurt treatments were evaluated for pH value, acidity, total phenolic compounds, antioxidant capacities, degree of hydrolysis, α-amylase and α-glucosidase inhibition, angiotensin-converting enzyme inhibition, antiproliferative activities, and rheological properties after 1 and 21 d of storage at 4°C. The results revealed that some of the investigated parameters were significantly affected by the starter culture strain and storage period. For instance, the effect of starter cultures was evident for the degree of hydrolysis, antioxidant capacities, proliferation inhibition, and rheological properties because these treatments led to different responses. Furthermore, the characteristics of camel milk-soy extract yogurt were also influenced by the supplementation level of soy extract, particularly after 21 d of storage. This study could provide valuable knowledge to the dairy industry because it highlighted the characteristics of camel milk-soy yogurt prepared with 2 different starter culture strains.

The aim of this study was to assess the effects of ultrafiltration (UF) combined with high-pressure processing (HPP) or heat treatment on the quality of soft cheese produced from camel milk (CM) or bovine milk (BM). Milk was concentrated by UF (0, 1, and 2-fold) before treatment with HPP at 350 MPa or 550 MPa for 5 min at 4 °C or by pasteurization at 65 °C for 30 min or at 75 °C for 30 s. Cheeses were produced using starter cultures and camel chymosin and pH, yield, proximate composition, texture profile, rheological properties, and protein profiles were determined. The highest yield of BM cheese (26%) was observed under the treatment with 2-fold UF combined with HPP at 550 MPa. CM cheese had the highest storage and loss moduli as well as the total solid and protein content under this treatment. According to SDS-PAGE electrophoresis, CM cheeses were more susceptible to proteolysis and had a higher number of low-molecular-weight bands, indicating the involvement of some active enzymes compared with BM cheeses. In conclusion, UF combined with HPP can enhance the cheese total solid content and gel structure in CM cheese products compared with heat treatment.

This study introduces a new and waste-to-waste treatment approach to isolate cellulose from lignocellulosic biomass. Rejected brine solution from desalination plant was utilized to remove noncellulosic components from the date palm leaves. Free chlorine available in rejected brine solution was responsible for the separation of cellulose from lignocellulosic structure. The proximate analysis revealed that the isolated cellulose exhibited a substantial volatile content of 83.70%, rendering it well-suited to produce bio-oil. Various other analytical techniques including FTIR, chemical composition analysis, proximate and ultimate analysis, X-ray diffraction (XRD), differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA) were employed to confirm the cellulose enrichment. Cellulose fibers with needle−shaped morphology were obtained. Cellulose fibers were having high thermal stability (Tonset = 250 ○C) and crystallinity index (64.75%) compared to raw waste (Tonset = 226 ○C; 53.58%). In addition, the activation energy (Ea) of both date palm leaves and isolated cellulose were investigated using the Coats−Redfern model−fitting method. The activation energy values obtained were 79.39 kJ/mol for date palm leaves and 103.27 kJ/mol for isolated cellulose. This research shows a completely new process for pretreatment of lignocellulosic wastes to isolate cellulose. This approach helps reduce the waste management cost associated with date palm waste and desalination plants to promote the concept of circular economy. Moreover, enriched cellulose derived from waste palm leaves using desalination brine presents sustainable options for eco−friendly packaging, textiles, biodegradable composites, and enhanced bio-oil production applications.

Developing insulating materials with minimal environmental impacts and enhanced properties has been the primary challenge in recent years. To address these challenges, date palm fiber (DPF) was treated with a silane coupling agent 3-aminopropyl triethoxysilane and two grafting solvents (acetone and ethanol) via the wet chemical method. The treated fibers were used to prepare poly(β-hydroxybutyrate) (PHB)-based composites via melt blending, thermo-compression molding, and annealing. The insulation properties of these green composites revealed that the silylated fiber composites possess an appropriate thermal conductivity, of 0.0901–0.106 W/(m·K). In cold and hot water, the silylated fiber composites drastically decreased water absorption by 20% and 34%, respectively. The tensile strength of the silylated fiber composites reached 18 MPa owing to improved compatibility, and the highest compressive strength was 48.6 MPa with a filler content of 40 wt%. The heat of combustion for silylated fiber composites ranged from 20.79 to 21.94 MJ/kg. The results indicate that silylated DPF-based PHB composites have potential for use in building engineering.

Oil-contaminated wastewater resulting from spills and discharges is a critical environmental pollution issue. In addition to the petrochemical industry, other well-known sources responsible for the discharge of oil-contaminated wastewater include the dairy industry, edible-oil refineries, the poultry-processing industry, and the pharmaceutical industry. Hence, separation of water from contaminated oil/water emulsion is necessary for its further use. Demulsification of oil/water emulsions provides the best alternative to deal with the oil contaminated wastewater and processing of crude oil and water emulsion after recovery before downstream processing. Demulsification techniques, particularly mechanical separation methods, can be highly energy consuming. To reduce operational expenses, energy efficiency is a key factor when developing demulsification systems. Chemical demulsification offers a cost-effective alternative for commercial applications. Recently, miscellaneous nanoparticle-based materials such as layered double hydroxides (LDHs) have been examined as chemical demulsifiers due to their ability to disturb the stability of oil/water emulsion. In particular, the different techniques that are employed to fabricate different types of LDH composites and membranes are considered of primary importance. Various LDH composites and membranes have been evaluated for demulsification of water and oil emulsions, and they have been found to provide excellent surface properties to serve the purpose of efficient separation of oil and water. Several advantages of LDH composites are also discussed. Numerous other applications for LDH composites are mentioned. Environmental concerns and their mitigation have been considered for future green synthesis of LDH composites.

ABSTRACT: Camel (CM) milk is used in variety of ways; however, it has inferior gelling properties compared with bovine milk (BM). In this study, we aimed to investigate the physicochemical, functional, microstructural, and rheological properties of low-moisture part-skim (LMPS) mozzarella cheese, made from BM, or BM mixed with 15% CM (CM15%) or 30% CM (CM30%), at various time points (up to 60 d) of storage at 4°C after manufacture. Low-moisture part-skim mozzarella cheeses using CM15% and CM30% had high moisture and total Ca contents, but lower soluble Ca content. Compared with BM cheese, CM15% and CM30% LMPS mozzarella cheese exhibited higher proteolysis rates during storage. Adding CM affected the color properties of LMPS mozzarella cheese manufactured from mixed milk. Scanning electron microscopy images showed that the microstructure of CM15% and CM30% cheeses had smooth surfaces, whereas the BM cheese microstructures were rough with granulated surfaces. Low-moisture part-skim mozzarella cheeses using CM15% and CM30% showed significantly lower hardness and chewiness, but higher stringiness than BM cheese. Compared with BM cheese, CM15% and CM30% cheeses showed lower tan δ levels during temperature surges, suggesting that the addition of CM increased the meltability of LMPS mozzarella cheese during temperature increases. Camel milk addition affected the physicochemical, microstructural, and rheological properties of LMPS mozzarella cheese.

Date palm and cashew shell wastes are abundant byproducts of the agriculture industry in the UAE, but they are often underutilized and not adequately managed, resulting in environmental problems. For the first time, co-pyrolysis of these wastes was studied to investigate their physicochemical properties, synergistic interaction, thermal degradation behavior, and estimate kinetic and thermodynamic parameters using thermogravimetric analysis with non-isothermal heating rates from 20 to 800 °C and a heating rate of 10 °C/min. The Coats and Redfern method, utilizing twenty-one solid-state reaction mechanisms, was used to perform analyses. The three diffusion models showed the best linear regression with the experimental thermogravimetric data. Co-pyrolysis of cashew shells with date seeds significantly lowered the activation energy (Ea) and produced stable biochar, providing an opportunity to obtain pyrolysis products at better energy efficiency. The estimated Ea for 100% date seeds, 100% cashew shells, and their blend (50:50) were 109, 124, and 113 kJ/mol, respectively. The thermodynamic parameters (ΔH, ΔG, and ΔS) indicated that the pyrolysis process was endothermic but not spontaneous. The novelty of this work lies in investigating the potential of utilizing two underutilized wastes together to produce pyrolysis products. This study is essential for advancing co-pyrolysis of date seeds and cashew shell wastes, optimizing product yields, and understanding their pyrolysis behavior towards experimental pyrolysis.

ABSTRACT: Camel milk (CM) can be used as an ingredient to produce various dairy products but it forms weak rennet-induced and acid-induced gels compared with bovine milk (BM). Therefore, in this study, we aimed to investigate the effect of blending bovine milk with camel milk on the physicochemical, rheological (amplitude sweep and frequency sweep), and microstructural properties of low-fat akawi (LFA) cheese. The cheeses were made of BM only or BM blended with 15% (CM15%) or 30% (CM30%) camel milk and stored at 4°C for 28 d. The viscoelastic properties as a function of temperature were assessed. The LFA cheeses made from blended milks had higher moisture, total Ca, and soluble Ca contents, and had higher pH 4.6–water-soluble nitrogen compared with those made from BM. Analysis by scanning electron microscopy demonstrated that the microstructures formed in BM cheese were rough with granular surfaces, whereas those in blended milk cheeses had smooth surfaces. Hardness was lower for LFA cheeses made from blended milk than for those made from BM only. The LFA cheeses demonstrated viscoelastic behavior in a linear viscoelastic range from 0.1 to 1.0% strain. The storage modulus (G′) was lower in LFA cheese made from BM over a range of frequencies. Adding CM reduced the resistance of LFA cheeses to flow as temperature increased. Blended cheeses exhibited lower complex viscosity values than BM cheeses during temperature increases. Thus, the addition of camel milk improved the rheological properties of LFA cheese.

Numerous people in African, Middle Asian, Middle Eastern, and Gulf Cooperation Council (GCC) countries highly value camel milk (CM) as it plays a vital role in their diet. The protein composition of CM as well as the structure of its casein micelles differs significantly from bovine milk (BM). Cheeses made from CM have a weak curd and soft texture compared to those made from BM. This review article presents and discusses the effect of milk protein composition, processing conditions (pasteurization and high-pressure treatment), and coagulants (camel chymosin, organic acids, plant proteases) on the quality of CM cheeses. CM cheese's weak texture is due to compositional characteristics of the milk, including low κ-casein-to-β-casein ratio (≈0.05 in CM vs. ≈0.33 in BM), large micelle size, different whey protein components, and higher proteolytic activity than BM. CM cheese texture can be improved by preheating the milk at low temperatures or by high pressure. Supplementing CM with calcium has shown inconsistent results on cheese texture, which may be due to interactions with other processing conditions. Despite their structure, CM cheeses are generally well liked in sensory studies.

As we enter the twenty-first century, the aviation sector is expected to thrive as flying becomes the primary mode of transportation between states or nations. With such a demand, there is a corresponding need to manufacture aircraft components. The study focused on recycling carbon fiber composites received from the STRATA company, which were cut-off/waste material generated during the manufacture of airplane components. The cut-offs were then reduced to powder form using a standard face milling machine in three sizes (90, 150, and 250 µm). After, the powder was utilized to fabricate vinyl ester composites with four weight percentages (10%, 20%, 30%, and 40%). The results demonstrate that the tensile strength of all composites had risen by 30.2%, 21.3%, and 17.6% for 90, 150, and 250 µm respective with the addition of 20 wt% of reinforcement. Furthermore, subsequently decreased with the additional reinforcement for all particle sizes. The compressive strength increased by 30% from 187.5 MPa to 244 MPa with 10 wt% of recycled carbon powder composite of 90μm particle size. However, samples prepared with 150 μm and 250 μm fiber size show approximately 17% and 1% increase in the compression strength with the addition of 10wt% of recycled carbon powder. A similar trend was observed for the flexural strength with an highest increase of 9% for 90 µm particle size with addition of 20 wt% reinforcement. Nonetheless, the SEM images revealed that the fiber–matrix bonding was weak, proved through the clean pullout fibers at the fracture surfaces.

Some of the major challenges of the twenty-first century include the continued increase in energy consumption and environmental pollution. One approach to overcoming these challenges is to increase the use of waste materials and environmentally friendly manufacturing methods. The high energy consumption in the building sector contributes significantly to global climatic changes. Here, by using date palm surface fibers, a high-performance green insulation material was developed via a simple technique that did not rely on any toxic ingredients. Polyvinyl alcohol (PVA) was used as a binding agent. Four insulation samples were made, each with a different density within the range of 203 to 254 kg/m3. Thermal conductivity and thermal diffusivity values for these four green insulators were 0.038–0.051 W/m·K and 0.137–0.147 mm2/s, respectively. Thermal transmittance (U-value) of the four insulation composites was between 3.8–5.1 W/m2·K, which was in good comparison to other insulators of similar thickness. Thermogravimetric analysis (TGA) showed that insulating sample have excellent thermal stability, with an initial degradation temperature of 282 °C, at which just 6% of its original weight is lost. Activation energy (Ea) analysis revealed the fire-retardancy and weakened combustion characteristics for the prepared insulation composite. According to differential scanning calorimetry (DSC) measurements, the insulating sample has a melting point of 225 °C, which is extremely close to the melting point of the binder. The fiber-based insulating material’s composition was confirmed by using Fourier transform infrared spectroscopy (FTIR). The ultimate tensile range of the insulation material is 6.9–10 MPa, being a reasonable range. Our study’s findings suggest that developing insulation materials from date palm waste is a promising technique for developing green and low-cost alternatives to petroleum-based high-cost and toxic insulating materials. These insulation composites can be installed in building envelopes during construction.

In this work, the effect of alkaline treatment on the thermal insulation and mechanical properties of date palm wood fibers (DPWF) and polylactic acid (PLA) green composite was studied. Alkaline treatment was applied to DPWF using two different solutions: sodium hydroxide (NaOH) and potassium hydroxide (KOH), with concentration of 2 vol.%. The fibers were later incorporated into PLA with weight percentages from 10 to 40 wt.%, to form three composite types: PLA with untreated fibers (PLA-UTDPWF), PLA with KOH treated fibers (PLA-KOH), and PLA with NaOH treated fibers (PLA-NaOH). The prepared composites were for use as a green thermal insulation material. The composites were tested to assess the effect of treatment on their physical (density and degree of crystallization), thermal (thermal conductivity, specific heat capacity, thermal diffusivity, thermal degradation, glass transition, and melting temperature), and mechanical properties. Moreover, the composite structural characteristics were investigated using FTIR and SEM analysis. The alkaline treatment significantly increased the crystallinity of the composites, specifically for higher filler loadings of 30 and 40 wt.%. The crystallinity for the 40 wt.% increased from 33.2% for PLA-UTDPWF, to 41% and 51%, for PLA-NaOH and PLA-KOH, respectively. Moreover, the alkaline treatment reduced the density and produced lighter composites than the untreated specimens. For instance, the density of 40 wt.% composite was reduced from 1.43, to 1.22 and 1.30 gcm3 for PLA-NaOH and PLA-KOH, respectively.

Petroleum-based plastic is widely used in almost all fields. However, it causes serious threats to the environment owing to its non-biodegradable properties, which necessitates finding biodegradable alternatives. Here, date palm rachis (DPR) waste was used as a filler (30, 40, and 50 wt%) to form a biodegradable composite with polylactic acid (PLA) and achieve cost–performance balance. DPR–PLA composites were prepared using a melt-mixing extruder at 180 °C by varying mixing time, DPR composition, and plasticizer type and composition. The biodegradable testing specimens were prepared by compression molding and analyzed using physical, thermal, and mechanical characterizations. Scanning electron microscopy images indicated a uniform dispersion of DPR (90 μm) in the PLA matrix. The esterification reaction resulting from this interaction between DPR and PLA was confirmed by Fourier transform infrared spectroscopy. The 30 wt% DPR–PLA composite was considered the optimal composite with the lowest melt flow index (16 g/10 min). This work confirmed the superior effect of addition of 10 wt% of triethyl citrate (TEC) compared with polybutylene adipate terephthalate (PBAT) by the improvement in the elongation at break of the optimal composite from 2.10% to 4.20%. Moreover, the addition of 10 wt% of PBAT to the optimal composite resulted in a lower tensile strength (21.80 MPa) than that of the composite with 10 wt% of TEC (33.20 MPa). These results show the potential of using the proposed composite as an alternative material for single-use plastics such as cutlery.

The massive production of Polyurethane foam from various products generates an extensive amount of waste, mostly in the form of dust that is emitted while cutting, trimming, or grinding the foam. In this research, the polyurethane dust (PUD) waste is incorporated into unsaturated polyester resin (UPR) to fabricate a heat insulation composite material to be used in construction. Filler percentages ranging from 10% to 50% were used to make the UPR-PUD composite materials. The thermal and mechanical properties of the material were studied in order to evaluate the ability of the composites for this type of application. Thermogravimetric Analysis and Differential Scanning Calorimeter tests were applied to determine the thermal stability of the material. In addition, the microstructure of the prepared composites and the incorporation of PUD filler into the polyester matrix were investigated by Scanning Electron Microscopy, X-ray diffraction (XRD), and Fourier-transform infrared spectroscopy (FTIR) analysis. The FTIR and XRD analyses suggested that adding PUD improved the curing process of unsaturated polyester and enhanced its crystalline structure. The experimental results showed promising thermal insulation capability, with low thermal conductivity in the range of 0.076 to 0.10 W/m·K and low water retention. Moreover, the composites exhibited compression strength between 56 and 100 MPa and tensile strength between 10.3 and 28 MPa, much higher than traditional thermal insulators and many building materials.

The utilization of greens resources is a grand challenge for this century. A lot of efforts are paid to substitute toxic ingredients of the conventional drilling mud system with nontoxic natural materials. In this paper, the effect of the natural polymer chitosan on the rheology and stability of sodium-bentonite drilling mud was investigated in the polymer concentration range of 0.1–3.0 wt.%. Both the shear and time dependent rheological properties of pure chitosan, pure bentonite and bentonite–chitosan dispersions were studied. Moreover, zeta potential measurements were used to evaluate the stability of bentonite-chitosan suspension. Adding chitosan improved the natural properties of drilling mud, namely: yield stress, shear thinning, and thixotropy. The viscosity of bentonite suspension increased significantly upon the addition of chitosan in the concentration range of 0.5 to 3.0 wt.% forming network structure, which can be attributed to the interactions of hydrogen bonding between -OH clusters on the bentonite surface with the NH group in the chitosan structure. On the other hand, dispersed chitosan–bentonite suspension was observed at low chitosan concentration (less than 0.5 wt.%). Increasing both bentonite and chitosan concentrations led to the flocculation of the bentonite suspension, forming a continuous gel structure that was characterized by noteworthy yield stress. The desired drilling mud rheological behavior can be obtained with less bentonite by adding chitosan polymer and the undesirable effects of high solid clay concentration can be avoided.

This study is aimed at developing a thermoplastic composite based on date pit powder waste for use as a thermal insulator in building industries. Date pits are the by-product of date stoning, either for the production of pitted dates or for the manufacture of date paste. The date pit powder (DPP) used in this study was obtained from the UAE University farm in Al Foah, UAE. DPP waste contents ranging from 0 wt.% to 50 wt.% were used to prepare the DPP-polystyrene composite. Date pit powder was mixed with polystyrene using a melt extruder, and then the mixture was transferred to the hot press to produce the final sample. The thermal and physical characteristics of the produced composites were measured experimentally and analyzed theoretically in terms of date pit and polystyrene properties. The characterized properties of the DPP-polystyrene composites, namely, density, thermal conductivity, water retention, thermal stability, and microstructure, showed that a stable composite material with insulation and construction capacity can be formed by the addition of date pit powder to the polystyrene matrix. The theoretical modeling of the measured thermal conductivity and the scanning electron microscope (SEM) monographs supported the hypothesis of date pit agglomeration in the composite matrix. The prepared composites showed low thermal conductivity (0.0515-0.0562 W/m K at 25°C) and very low density (457-630 kg/m3), thus demonstrating their potential for use as a thermal insulator for building materials. In addition, replacing one-third of the classical construction wall content with DPP-polystyrene composite showed promise for constructive applications as a thermal insulator with 85% reduction in the overall thermal conductivity. Indeed, these properties are similar to those of other conventional insulating materials. This will lead to produce an inexpensive insulation material that exploits a common waste product in date fruit-producing countries.

Bauxite residue (BR) is one of the most commonly generated industrial wastes in the world. Thus, novel techniques for its proper utilization must be urgently developed. Herein, seawater-neutralized BR–unsaturated polyester resin (UPR) composites are presented as insulating construction materials with promising mechanical performance. Composites with different BR content (0–60 vol.%) were prepared to evaluate the influence of BR content on the compressive, tensile, and flexural strengths as well as the moduli of BR–UPR composites. Experimental results revealed that adding BR particles to the polyester matrix increased the compressive properties (strength, modulus, and strain). The composites containing 20 vol.% BR showed the maximum compressive strength (108 MPa), while the composites with 30 vol.% BR exhibited the maximum compressive modulus (1 GPa). Moreover, the reduction in tensile and flexural strengths with an increase in the BR content may be attributed to the lower efficiency of stress transfer between the BR particle–polyester interface due to weak adhesion at the interface, direct contact between particles, and presence of voids or porosity. Although the tensile strength and failure stress decreased with increasing filler content, the produced composites showed outstanding tensile strength (4.0–19.3 MPa) compared with conventional insulating materials. In addition, the composite with 40 vol.% BR demonstrated a flexural strength of 15.5 MPa. Overall, BR–UPR composites showed excellent compatibility with promising mechanical properties as potential insulating construction materials.

This work aims to provide an extensive evaluation on the use of polylactic acid (PLA) as a green, biodegradable thermal insulation material. The PLA was processed by melt extrusion followed by compression molding and then subjected to different annealing conditions. Afterwards, the thermal insulation properties and structural capacity of the PLA were characterized. Increasing the annealing time of PLA in the range of 0–24 h led to a considerable increase in the degree of crystallization, which had a direct impact on the thermal conductivity, density, and glass transition temperature. The thermal conductivity of PLA increased from 0.0643 W/(m·K) for quickly-cooled samples to 0.0904 W/(m·K) for the samples annealed for 24 h, while the glass transition temperature increased by approximately 11.33% to reach 59.0 °C. Moreover, the annealing process substantially improved the compressive strength and rigidity of the PLA and reduced its ductility. The results revealed that annealing PLA for 1–3 h at 90 °C produces an optimum thermal insulation material. The low thermal conductivity (0.0798–0.0865 W/(m·K)), low density (~1233 kg/m3), very low water retention (