Date Palm Tree Waste Recycling: Treatment and Processing for Potential Engineering Applications

Evaluation, optimization study, and life cycle assessment of novel eco-friendly PVA-based nanocomposite hydrogel adsorbents for methylene blue and paracetamol removal

In this study, an eco-friendly and novel hydrogel based on a crosslinked polyvinyl alcohol (PVA), iota carrageenan (IC) and polyvinylpyrrolidone (PVP) scaffold, containing a large amount (10-50 wt%) of nanoscale palm fronds (NPF) as additives, for water purification was demonstrated. A life cycle assessment (LCA) findings on NPF as biomass waste incorporated into PVA_PVP_IC polymer matrix was presented, and the results highlight the necessity of focused actions to reduce environmental impact and support the palm waste utilization in a sustainable manner. The multicomponent nanocomposite hydrogels were examined as adsorbents in a system work in batches for methylene blue (MB) and paracetamol (PCT) removal. The results show that, the presence of NPF, which dispersed in the hydrogel PVA_PVP_IC scaffolds containing both covalent and non-covalent cross-linking bonds, greatly enhanced the MB and PCT adsorption efficiency. A response surface methodology (RSM) model was used to find the best operating parameters of contaminant adsorption, including time, adsorbent dose, and starting concentration of pollutants. By using this statistical model, it was found that the optimal conditions for the adsorption reaction to achieve the complete removal of MB are 66.7 h adsorption time duration, 98.5 mg L-1 starting concentration, and an adsorbent dose of 5.9 mg, while for the complete removal of PCT, it is 57.6 h adsorption time duration, 80 mg L-1 starting concentration, and an adsorbent dose of 6 mg. The reusability of the nanocomposite hydrogels were tested for 5 cycles, all showed high adsorption capacity, indicating the potential for practical application of this nanocomposite hydrogel system. This study indicates that the prepared nanocomposite hydrogel raises the standard used for treatment of wastewater and also gives a solution to protect the environment and mitigate global warming.

Effect of benzoyl chloride treatment on morphological, thermal, mechanical, and hydrothermal aging properties of date palm/polyvinyl chloride (PVC) composites

The use of natural fibers has seen a significant rise in the composites sector, resulting in the creation of polymer composites with exceptional strength. These environmentally-friendly alternatives offer a compelling substitute for synthetic composites. This study explores the use of date palm waste as reinforcement for the fabrication of polyvinyl chloride (PVC) composites. A surface modification method was essential for improving the binding interaction between palm fibers and PVC composites. The two-hour benzoyl chloride treatment at 140 °C played a crucial role. The study examined the effects of hydrothermal aging on mechanical properties of composites, using various techniques such as surface morphology analysis, Fourier Transform Infrared spectroscopy, and Thermogravimetric Analysis, on composites made of untreated fibers and those treated with benzoyl chloride. Although the treatment of palm fiber-reinforced composites with benzoyl chloride improved their mechanical properties, it is crucial to note that hydrothermal aging reduced their tensile strength by 10%. Despite this, these composites prove to be well-suited for applications requiring moderate strength and stiffness in mild environmental conditions. These composites, while utilizing benzoyl chloride for surface treatment, still represent a more sustainable alternative to traditional synthetic composites by incorporating renewable date palm waste and enhancing mechanical properties, which potentially reduces overall environmental impact.

Synthesis of hydrochar from date palm seeds using microwave-enhanced hydrothermal carbonization and its application in dyes removal

This work reports new findings on the preparation of hydrochar from date palm (Phoenix dactylifera) seeds through the application of the microwave hydrothermal carbonization (HTC) method. Optimization investigations involving temperatures and reaction times were conducted to establish the highest yield, achieving a maximum yield of 60.87%. The prepared material was then impregnated in phosphoric acid and carbonized in the tube furnace at 550 °C for 1.5 h with a nitrogen flow of 50 CCM. The samples were characterized via scanning electron microscopy (SEM), Brunauer-Emmet-Teller (BET) and Fourier transform infrared (FTIR). The samples showed remarkable BET surface areas following activation, reaching up to 992 m2·g-1. The substance was subsequently used to absorb methylene blue with good fitting to the Freundlich and Redlich-Peterson isotherm and achieved a peak adsorption capacity of 196.6 ± 3.9 mg·g-1.

Removal of heavy metals from wastewater by aerogel derived from date palm waste

Cellulose that has been sourced from date palm leaves as a primary component was utilised. This cellulose served as the foundational material for the development of an aerogel composite. During this process, MXene (Ti3C2Tx) played a pivotal role in enhancing the overall composition of the aerogel. To ensure the stability and durability of the resulting aerogel structure, calcium ions were introduced to the mix. These ions facilitated the cross-linking process of sodium alginate molecules, ultimately leading to the formation of calcium alginate. This cross-linking step is crucial for the enhanced mechanical and chemical stability of the aerogel. Incorporating alginate and Ti3C2Tx into the cellulose aerogel enhanced its structural integrity in aqueous conditions and increased its adsorption capacity. When evaluated with synthetic wastewater, this composite exhibited remarkable adsorption capacities of 72.9, 114.4, 92.9, and 123.9 mg/g for As, Cd, Ni, and Zn ions, respectively. A systematic study was carried out to see the effect of various parameters, including contact time, MXene concentration, pH, and temperature on the adsorption of these elements. Peak adsorption was achieved at 60 min, favoring a pH range between 6 and 8 and exhibited optimal sorption efficiency at lower temperatures. The adsorption kinetics adhered closely to a pseudo-second-order, while the Freundlich model adeptly described the adsorption isotherms. An interesting result of this research was the aerogel's regenerative potential. After undergoing a basic acid treatment, the MXene/cellulose/alginate aerogel composite could be restored and reused for up to three cycles, all while maintaining its core performance capabilities even after the rigorous cross-linking processes. In three consecutive cycles, the removal percentages for As, Cd, Ni, and Zn were 48.15%, 80.38%, 56.51%, and 86.12% in cycle 1; 37.35%, 65.63%, 45.97%, and 78.42% in cycle 2; and 28.60%, 56.22%, 34.70%, and 65.83% in cycle 3, respectively. The composite was tested in conditions resembling seawater salinity. Impressively, the aerogel continued to demonstrate a significant ability to adsorb metals, reinforcing its potential utility in real-world aquatic scenarios. These findings suggest that the composite aerogel, integrating MXene, cellulose, and alginate, is an effective medium for the targeted removal of heavy metals from aquatic environments.

Using Date Palm Waste as an Alternative for Rockwool: Sweet Pepper Performance under Both Soilless Culture Substrates

The degradation of soil quality due to environmental conditions and improper management practices has caused a shrinkage in land areas suitable for crop cultivation. This necessitates a transition towards soilless culture systems, which offer desirable conditions for crop growth and development and increase resource use efficiency. One of the growth-limiting factors in soilless culture systems is the type of growing substrate. The use of more sustainable resources and environmentally friendly growing substrates is a challenge that affects the soilless culture industry. This work evaluates the efficacy of date palm waste (DPW) and rockwool as growing substrates for sweet pepper (Capsicum annuum L.) under greenhouse conditions. The plant height, stem diameter, average total leaf area, φPSII, and Fm' of leaf fluorescence show significant increases when plants are grown in rockwool. No differences are found in terms of the total yield or the number of marketable fruits and fruit quality between the two substrates. However, the DPW substrate shows a significant decrease in the number of unmarketable fruits and number of Blossom End Rot (BER) fruits. Plants grown in both growing substrates consume equal water amounts for the optimal fruit production, while the water use efficiency of rockwool is better than that of DPW. Our results highlight DPW's role in soilless production and as a key solution for resource-saving production systems.

Promising anti-Helicobacter pylori and anti-inflammatory metabolites from unused parts of Phoenix dactylifera CV 'Zaghloul': in vitro and in silico study

CONTEXT

Date palm waste is an agricultural waste that accumulates in massive amounts causing serious pollution and environmental problems.

OBJECTIVES

Date palm trees, Phoenix dactylifera Linn CV 'Zaghloul' (Arecaceae) grown in Egypt, leave behind waste products that were investigated to produce compounds with anti-Helicobacter pylori and anti-inflammatory activities.

MATERIALS AND METHODS

Chromatographic workup of P. dactylifera aqueous methanol extract derived from fibrous mesh and fruit bunch (without fruit) afforded a new sesquiterpene lactone derivative, phodactolide A (1), along with ten known compounds (2-11), primarily identified as polyphenols. Chemical structures were unambiguously elucidated based on mass and 1D/2D NMR spectroscopy. All isolated compounds were assessed for their activities against H. pylori using broth micro-well dilution method and clarithromycin as a positive control. The anti-inflammatory response of isolated compounds was evaluated by inhibiting cyclooxygenase-2 enzyme using TMPD Assay followed by an in silico study to validate their mechanism of action using celecoxib as a standard drug.

RESULTS

Compounds 4, 6 and 8-10 exhibited potent anti-H. pylori activity with MIC values ranging from 0.48 to 1.95 µg/mL that were comparable to or more potent than clarithromycin. For COX-2 inhibitory assay, 4, 7 and 8 revealed promising activities with IC₅₀ values of 1.04, 0.65 and 0.45 μg/mL, respectively. These results were verified by molecular docking studies, where 4, 7 and 8 showed the best interactions with key amino acid residues of COX-2 active site.

CONCLUSION

The present study characterizes a new sesquiterpene lactone and recommends 4 and 8 for future in vivo studies as plausible anti-ulcer remedies.

Life Cycle Assessment of Production of Hydrochar via Hydrothermal Carbonization of Date Palm Fronds Biomass

This study presents novel life cycle assessment (LCA) findings on hydrochar production from Saudi-Arabia-based date palm fronds biomass waste using hydrothermal carbonization (HTC). The LCA procedure incorporated normalization, weighting, and improvement assessment. The system boundary encompassed water consumption and energy requirements within a lab setting representing a gate-to-gate process. The OpenLCA 1.11.0 software with the European Life Cycle Database 3.2 (ELCD 3.2) was utilized for the study and we employed the ReCiPe Midpoint (H) 2016 and Environmental Footprint 3.0 (EF 3.0) impact assessment methods. The results indicated that fossil fuel usage represented the most significant impact category with the HTC and drying processes identified as major contributors. It was also observed that the HTC process exerted far greater detrimental impacts on the environment than the biomass grinding process. The overwhelming impact of fossil fuel resources could be mitigated by optimizing the batches of biomass or hydrochar samples in each operation, which could alleviate fossil fuel consumption by up to 94%. The findings emphasize the need for targeted interventions to mitigate the environmental burden and contribute to sustainable hydrochar production.

Sustainable Preparation of Graphene Quantum Dots from Leaves of Date Palm Tree

The date palm (Phoenix dactylifera), a subtropical and tropical tree, included in the family Palmae (Arecaceae) is one of the oldest cultivated plants of mankind. Date palm is a major agricultural product in the semi-arid and arid areas of the world, particularly in Arab countries. These trees generate high quantities of agricultural waste in the form of dry leaves, seeds, etc. In this study, dried date palm leaves were used as green precursors for synthesizing graphene quantum dots (GQDs). This work reported the preparation of GQDs using two different sustainable methods. GQD-1 was developed using a simple, hydrothermal technique at 200 °C for 12 h in water, with no requirement of reducing or passivizing agents or organic solvents. GQD-2 was prepared using a hydrothermal technique at 200 °C for 12 h in water, with the usage of just distilled water and absolute ethanol. The compositional analysis of the leaf extract was performed, along with the morphological, compositional, and optical examination of the sustainably developed GQDs. The characterization results confirmed the successful formation of GQDs, with average sizes ranging from 3.5 to 8 nm. This study helps to obtain GQDs in an economical, eco-friendly, and biocompatible manner and can assist in large-scale production and in recycling date palm tree waste products from Middle East countries into value-added products.

Epoxy–Date Palm Fiber Composites: Study on Manufacturing and Properties

Epoxy-date palm fiber (DPF) composites have been synthesized and characterized successfully with various reinforced ratios of DPF (i.e., 5, 10, 15, and 20 wt%), where the mixture of Epoxy–DPF is poured into different prepared silicone molds. The first type of silicon molds is prepared to produce the samples of the Epoxy–DPF composites to conduct mechanical tests (i.e., impact, creep, and tensile). When the ratio of DPF is increased in the Epoxy matrix, a significant improvement was observed in the results of the mechanical tests. The Epoxy–DPF composites with 15 wt% exhibit a high hardness of 38.4 in comparison with other composite specimens. Maximum impact strength, creep strain, and tensile strengths were recorded to be 0.13 J/mm2, 0.03112, and 23.4 N/mm2, respectively, using 20 wt% DPF.

Lignin-Containing Cellulose Nanofibrils from TEMPO-Mediated Oxidation of Date Palm Waste: Preparation, Characterization, and Reinforcing Potential

Lignin-containing cellulose nanofibrils (LCNFs) have emerged as a new class of nanocelluloses where the presence of residual lignin is expected to impart additional attributes such as hydrophobicity or UV-absorption. In the present work, LCNFs with a lignin content between 7 and 15 wt% were prepared via a TEMPO-mediated oxidation as chemical pretreatment followed by high-pressure homogenization. The impact of the carboxyl content (CC) on the properties of the resulting LCNF gel, in terms of lignin content, colloidal properties, morphology, crystallinity, and thermal stability, were investigated. It was found that lignin content was significantly decreased at increasing CC. In addition, CC had a positive effect on colloidal stability and water contact angle, as well as resulting in smaller fibrils. This lower size, together with the lower lignin content, resulted in a slightly lower thermal stability. The reinforcing potential of the LCNFs when incorporated into a ductile polymer matrix was also explored by preparing nanocomposite films with different LCNF contents that were mechanically tested under linear and non-linear regimes by dynamic mechanical analysis (DMA) and tensile tests. For comparison purposes, the reinforcing effect of the LCNFs with lignin-free CNFs was also reported based on literature data. It was found that lignin hinders the network-forming capacity of LCNFs, as literature data shows a higher reinforcing potential of lignin-free CNFs. Nonetheless, the tensile strength of the acrylic matrix was enhanced by 10-fold at 10 wt% of LCNF content.

Development of Hybrid Composite Utilizing Micro-Cellulose Fibers Extracted from Date Palm Rachis in the Najran Region

Environmental effects can be reduced by using renewable resources in various applications. The date palm fibers (DPF) used in this study were extracted from waste date ranches of the Najran region by retting and manual peeling processes. The biocomposites were developed by reinforcing the silane-treated DPF (SDPF) at different wt.% in eugenol phthalonitrile (EPN) and difunctional benzoxazine (BA-a) copolymer. The impact strength, tensile, flexural, and dynamic mechanical properties and thermogravimetric analysis were evaluated to understand the mechanical, thermomechanical, and thermal properties. Results confirmed that 30 wt.% SDPF-reinforced poly (EPN/BA-a) composites produced the highest mechanical and thermomechanical properties, and were considered optimized SDPF reinforcement. Furthermore, hybrid composites with 30 wt.% SDPF and 15 wt.% silane-treated glass fibers (SGF) reinforcement having different lamination sequences were also studied. The lamination sequences showed a significant impact on the mechanical and thermomechanical properties, as properties were further enhanced by adding a core layer of SGF in hybrid composites. However, the thermal properties of SDPF/SGF laminates were higher than SDPF biocomposites, but the SGF lamination sequence did not produce any impact. According to the limiting oxygen and heat resistance indexes, the developed SDPF/SGF laminates are self-extinguishing materials and can be used in temperature-tolerant applications up to 230 °C.

Treatment of heavy metals contaminated water: use of B. mojavensis BI2 derived lipopeptide and palm waste flour

In the present work, we demonstrated the potential use of newly identified lipopeptides produced by B. mojavensis BI2 along with palm waste flour for the bioremediation of heavy metals contaminated water. The enhancement of radish seeds germination was used to evaluate the treatment efficiency. Firstly, better enhancement in the order of 3.8, 2.52, 1.5 and 5 were recorded respectively for 200 mg/L copper, lead, cobalt and mercury with respective lipopeptide quantities of the order of 200, 300, 200 and 400 mg/L. When studying the sequestration of increasing heavy metals concentration, BI2 lipopeptide was effective. Secondly, a mixed bioprocess was evaluated using palm waste flour as heavy metals sequester and BI2 lipopeptides as improver. Optimal biosorption of lead, copper, cobalt and mercury were obtained with 10 g/l waste, 1,000 mg/l metal and 200 mg/l BI2 lipopeptide for 1 hour. The addition of 200 mg/l BI2 lipopeptide improves the efficiency of the treatment significantly.

Facile Preparation and Analytical Utility of ZnO/Date Palm Fiber Nanocomposites in Lead Removal from Environmental Water Samples

This study reports a facile approach for preparing low-cost, eco-friendly nanocomposites of ZnO nanoparticles (NPs) and date palm tree fiber (DPF) as a biomass sorbent. The hypothesis of this research work is the formation of an outstanding adsorbent based on the date palm fiber and ZnO nanoparticles. ZnO NP/DPF nanocomposites were synthesized by mixing the synthesized ZnO NPs and DPF in different mass ratios and evaluating their efficacy in adsorbing Pb2+ from aqueous solutions. The structure and surface morphology of the developed ZnO NP/DPF nanocomposite were critically characterized by XRD, FESEM, and TEM techniques. Compared to ZnO NPs, the ZnO NP/DPF nanocomposites displayed significantly enhanced Pb2+ uptake. Pb2+ adsorption was confirmed via various isotherm and kinetic models and thermodynamics. The computed Langmuir sorption capacity (qm) was found to be 88.76 mg/g (R2 > 0.998), and the pseudo-second-order R2 > 0.999 model was most appropriate for describing Pb2+ adsorption. Impregnating the biomass with ZnO NPs enhanced the spontaneity of the process, and the value (−56.55 kJ/mol) of ΔH displayed the exothermic characteristics of Pb2+ retention. Only the loaded ZnO NP/DPF achieved the removal of a high percentage (84.92%) of Pb2+ from the environmental water sample (seawater). This finding suggests the use of ZnO NP/DPF nanocomposites for removing heavy metals from environmental water samples to purify the samples.

Mechanical Behavior of Epoxy Reinforced by Hybrid Short Palm/Glass Fibers

Natural fibers (NFs) have recently been the center of attention among researchers due to their low cost, availability, ease of manufacture, and potential environmental friendliness as reinforcing agents in composites. The present work deals with the mechanical behavior of palm fiber-reinforced epoxy-based composites with different weight percentage (Wt.%) ratios, ranging from 6% to 31.6%. Glass and hybrid fiber-reinforced epoxy-based composites were also examined. The indirect tensile test, i.e., diametral tensile test (DTT) and the small punch test (SPT), were used in the present work to determine the mechanical properties of the epoxy reinforced with discontinuous random oriented short fibers. Furthermore, short glass fibers were used to compare with palm fiber-reinforced epoxy. In addition, morphology observations of epoxy residue clinging to the natural fibers were carried out using the optical microscope and Scanning Electron Microscopy (SEM). The results showed that the natural fiber has a better adhesion bonding between the palm fiber/epoxy than that of glass fiber/epoxy. Therefore, adding palm fibers improves epoxy’s mechanical properties compared with synthetic glass fibers. The composite with high Wt.% of NF showed the highest diametral tensile strength (DTS), 21.74 MPa, over other composites. The DTS of composites with medium and low Wt.% of NF was lower than that of the high Wt.% by 14% and 30%, respectively.

Review of Bioenergy Potential from the Agriculture Sector in Iraq

Bioenergy is one of the most important renewable-energy sources worldwide, accounting for more than two-thirds of the renewable-energy mix. Biomass accounted for 13–14% of the primary energy consumption in 2018, and by 2050, it is expected to account for 50% of the global primary energy consumption. This article studies the biomass potential in Iraq. The potential of this country to be one of the leading producers of bioenergy is discussed, remarking on the importance of agricultural crop waste. Nowadays, Iraq generates a great quantity of biomass every year. Unfortunately, instead of contributing to the energy industry and economic progress, these wastes are burned directly, potentially causing a slew of environmental issues. Based on earlier studies, the theoretical energy potential of Iraq agricultural wastes is assessed. It is concluded that 10 million tons of dry agricultural leftovers can create 115 PJ of energy per year. According to the findings of this study, 10 million heads of cattle in Iraq could generate 72 million m3 of biogas per day, with a total potential power of 946 TJ per year from animal wastes, mainly cattle dung. On the other hand, bioenergy potential is heavily reliant on the geographical distribution, availability, and accessibility of real waste. Wasit, Qadisiyah, and Mosul are the most feasible locations for this agricultural waste potential. This might lead to the development of a long-term economic plan for the successful and sustainable utilization of important accessible waste for bioenergy generation.