A groundbreaking study published in Environmental Science and Pollution Research in 2025 has revealed that date palm seed biomass (DPSB) can effectively remove uranium (VI) ions from contaminated water with an efficiency of up to 76%.
This innovative research, conducted by an international team of scientists, provides a sustainable and low-cost solution to uranium pollution a growing environmental concern near mining sites and nuclear facilities.
Uranium in water causes serious health risks, including kidney damage and cancer, while traditional treatment methods are costly and generate toxic waste.
Therefore, the use of agricultural waste from date processing offers a promising alternative that delivers comparable results at a fraction of the cost.
In this context, the use of DPSB in uranium water treatment presents a significant advancement in sustainable water remediation.
To further explain, uranium (VI) ions are uranium atoms in their hexavalent state, which are commonly found in water as soluble complexes. The oxidation state is crucial because it affects how uranium interacts with adsorbents like DPSB.
Additionally, biomass in this study refers to organic material specifically date palm seeds used as a natural and low-cost adsorbent to remove pollutants from water.
The Problem of Uranium Contamination
Exposure to uranium has been linked to serious health risks, including nephrotoxicity, which is the potential of a substance to cause damage to the kidneys, and an increased risk of cancer as reported by the World Health Organization.
Moreover, mining activities are known to release uranium into nearby water sources, with reported levels ranging between 0.5 and 5 mg/L.Uranium contamination in water is a significant global issue.
These environmental releases contribute to the deterioration of water quality and pose a danger to both human health and local ecosystems.
Furthermore, the economic burden of treating contaminated water is high. Traditional remediation techniques, which use synthetic adsorbents, often exceed costs of $50 per cubic meter, making these approaches less viable for large-scale applications.
In addition, existing solutions such as synthetic resins and chemical precipitation have their own limitations. Synthetic resins tend to lose efficiency after just 5 to 7 cycles, while chemical precipitation generates sludge that requires special disposal methods.
Activated carbon systems, on the other hand, can be extremely expensive, costing between $300 and $500 per kilogram. As a result, there is a growing need for alternative methods that are not only cost-effective but also environmentally friendly.
Unique Chemical Composition and Performance Advantages
Date palm seeds have a unique chemical composition that makes them highly effective for use in water treatment.
Analysis of DPSB reveals that it contains 23% lignin and 75% holocellulose, which contribute significantly to its structure and functionality.
Lignin provides rigidity and chemical resistance, while holocellulose forms the fibrous framework that is crucial for adsorption. Moreover, DPSB contains functional groups such as carboxyl, hydroxyl, and phenolic groups.
These groups are key because they actively interact with uranium ions through chemical bonding, thus enhancing the adsorption process.It is important to note that the advantages of DPSB extend beyond its chemical makeup.
Comparative studies have shown that date palm seed biomass achieves 30% higher uranium uptake than coconut shells, is 45% more efficient than rice husk biochar, and exhibits performance comparable to that of graphene oxide yet at only 1/1000th the cost.
Such high adsorption efficiency, combined with its low price, underscores the potential of DPSB for sustainable uranium water treatment applications.
Biomass Preparation and Process Optimization
The process of preparing date palm seed biomass for uranium water treatment involves several well-defined steps. First, the seeds are washed with n-hexane to remove oils that might interfere with the adsorption process.
Following this, the seeds are dried at 150°C for 24 hours to ensure that all moisture is removed, which is essential for maintaining consistency in the treatment process. After drying, the seeds are ground into fine particles ranging from 150 to 180 μm.
This reduction in particle size is critical because it increases the surface area available for adsorption, thereby enhancing the efficiency of the process.
Notably, no chemical activation is required during this process, which simplifies the procedure and reduces the overall cost.
In addition to the physical preparation of the biomass, the researchers also tested various experimental parameters to determine the optimal conditions for uranium removal.
They experimented with a range of temperatures from 25°C to 55°C, pH levels from 2 to 11, initial uranium concentrations from 1 to 20 mg/L, and contact times from 0 to 180 minutes.
Through this systematic approach, the optimal conditions were found to be a temperature of 55°C, a pH of 7, an initial concentration of 20 mg/L, and a contact time of between 60 and 90 minutes.
Furthermore, the adsorption process was analyzed in detail. For instance, temperature effects were found to be significant at 55°C, the uranium removal efficiency reached 76%, compared to 70% at 25°C.
The equilibrium time—the time required for the adsorption process to stabilize—was reduced from 90 minutes at 25°C to 60 minutes at 55°C. Thermodynamic analysis indicated that the process is endothermic, as evidenced by a positive ΔH° value of 10,794.9 J/mol.
Adsorption Kinetics and Mechanisms
The adsorption kinetics of DPSB were thoroughly investigated, and the process was best described by the pseudo-second-order kinetic model.
This model indicates that chemisorption the formation of chemical bonds between the adsorbate and adsorbent is the rate-limiting step.
In this study, the rate constants varied between 0.089 and 0.713 g/mg/min, indicating a strong chemical interaction between the uranium ions and the DPSB.
This strong interaction is essential for ensuring that the uranium remains bound to the biomass, which is a critical factor in effective uranium water treatment.In addition to kinetics, the isotherm analysis provided further insight into the adsorption process.
The Langmuir isotherm model, which assumes a homogenous surface with a fixed number of adsorption sites, fit the experimental data very well, with an R² value of 0.9995.This suggests that the adsorption occurs as a monolayer on the DPSB surface.
However, the Freundlich isotherm model, which accounts for heterogeneous surface energies, also showed a high correlation, indicating that some level of surface heterogeneity exists.
Both of these models are valuable because they help predict how DPSB will perform under different conditions, further validating its use in uranium water treatment.
Another important aspect of the adsorption process is intra-particle diffusion. The study revealed that this process occurs in three distinct phases.
Initially, there is a rapid surface adsorption phase that occurs within the first 20 minutes, followed by a gradual pore diffusion phase between 20 and 60 minutes.Finally, the process reaches equilibrium after more than 60 minutes.
Economic and Environmental Advantages of DPSB
When comparing DPSB with commercial adsorbents, the advantages become even more apparent. For example, DPSB costs only $0.50 per kilogram and has an adsorption capacity of 8.64 mg/g.
In contrast, activated carbon costs around $300 per kilogram and has a capacity of 9.12 mg/g, while ion exchange resins are even more expensive at $450 per kilogram with a capacity of 10.25 mg/g.
Graphene oxide, another advanced material, costs a staggering $2,000 per kilogram while offering a capacity of 12.40 mg/g.The cost-effectiveness of DPSB is not only economically beneficial but also environmentally friendly.
Despite these differences, DPSB’s low cost and competitive performance make it highly attractive for large-scale uranium water treatment, especially in resource-limited regions.
The use of an agricultural byproduct means that waste materials are repurposed, reducing the environmental impact associated with conventional water treatment methods.
Moreover, the high adsorption efficiency achieved with DPSB implies that fewer chemicals and less energy are needed to treat contaminated water.
This combination of low cost, high efficiency, and reduced environmental impact positions DPSB as a leading candidate in the field of sustainable uranium water treatment.
Practical Applications
The practical applications of DPSB in water treatment systems are extensive. One promising application is the development of column filtration systems that can process up to 500 liters of water per day.
Such systems would be particularly useful in communities near uranium mining sites or areas affected by industrial pollution. The expected operational cost of these systems is as low as $0.02 per liter, making them an affordable solution for large-scale water remediation projects.
Additionally, DPSB offers waste management benefits since global date production of about 9.5 million tons annually provides ample agricultural waste that can be repurposed as an effective uranium adsorbent.
By repurposing this waste, the need for hazardous chemical treatments is reduced, and overall environmental sustainability is improved.
These benefits are particularly important for regions that require reliable and cost-effective uranium water treatment solutions, as well as for areas that aim to reduce their environmental footprint.
Moreover, the success of DPSB in laboratory settings suggests that its application could be expanded to various water treatment systems worldwide.
For instance, communities in developing nations, where the cost of conventional water treatment methods is prohibitive, could benefit immensely from the use of DPSB.
In addition, industries that generate uranium-contaminated wastewater could implement DPSB-based treatment systems as a cost-effective and eco-friendly alternative to traditional methods.
This broad applicability demonstrates the far-reaching potential of DPSB as a transformative material in the field of uranium water treatment.
Limitations and Future Research
Despite its promising performance, the use of DPSB in uranium water treatment does have some limitations. One of the main challenges is that the biomass requires pH adjustment to achieve optimal performance.
The optimal pH for maximum uranium removal is found to be 7, which means that water samples with a pH significantly different from neutral may need to be adjusted before treatment.
Additionally, while the maximum adsorption capacity of DPSB is impressive, it is still lower than that of some synthetic materials. This limitation suggests that there is room for improvement in the efficiency of DPSB.
In light of these challenges, ongoing research is focused on further developing and optimizing DPSB. For example, researchers are currently testing modified DPSB that has been treated with phosphate groups.
Preliminary results indicate that this modification can lead to a 12% increase in uranium removal efficiency. Furthermore, field trials are being planned in Jordanian uranium mining regions to evaluate the performance of DPSB under real-world conditions.
These trials will provide valuable insights into the scalability of the technology and help refine the process for broader application in uranium water treatment.
Future research will likely explore additional modifications to DPSB and investigate ways to further enhance its adsorption capacity.
Researchers are also interested in understanding the long-term performance and regeneration potential of DPSB, as these factors are crucial for the sustainable operation of water treatment systems.
Conclusion
In conclusion, this study shows that date palm seed biomass (DPSB) can remove uranium from water with 76% efficiency at a fraction of the cost of traditional methods. Its natural abundance and simple processing make DPSB a sustainable and economical solution for uranium water treatment.
The findings highlight its potential to improve water quality and public health while reducing environmental impact, paving the way for broader adoption and future innovations in eco-friendly water remediation.
Power Terms
Uranium (U(VI)): A radioactive heavy metal that exists as uranyl ions (UO₂²⁺) in water. It enters water systems through mining, nuclear accidents, or industrial waste, posing serious health risks like kidney damage and cancer. In this study, uranium is removed from contaminated water using date palm seed biomass as a natural filter.
Biosorption: The natural process where biological materials capture and bind pollutants like heavy metals. Unlike artificial filters, biosorption uses cheap, renewable materials like plant waste. Date palm seeds in this research demonstrate excellent uranium-binding capabilities through this eco-friendly method.
Date Palm Seed Biomass (DPSB): Crushed, dried seeds from date palms (Phoenix dactylifera), typically discarded as agricultural waste. Rich in cellulose and lignin, DPSB contains oxygen-rich functional groups that chemically trap uranium ions. Its use transforms waste into a valuable water-purification tool.
Green Remediation: Environmentally sustainable pollution-cleanup methods that minimize chemical use and energy consumption. This study exemplifies green remediation by repurposing DPSB – a natural, biodegradable material – instead of synthetic resins or energy-intensive filtration systems.
Sorption: An umbrella term for processes where substances (like uranium) accumulate on a solid material’s surface (adsorption) or within its structure (absorption). The research examines how uranium sorbs onto DPSB through both physical attachment and chemical bonding.
Adsorption Capacity (qₑ): The maximum amount of uranium (measured in milligrams) that one gram of DPSB can capture. Calculated using the formula
qₑ = (Cᵢ – Cₑ)/S,
where Cᵢ and Cₑ are initial and final uranium concentrations, and S is the DPSB dosage. Higher qₑ values indicate better performance.
pH: A 0-14 scale measuring water’s acidity/alkalinity that dramatically affects uranium removal. At pH 7 (neutral), DPSB achieved 72% uranium capture because both the biomass surface and uranium ions carried optimal charges for binding. Extreme pH values reduced efficiency.
Kinetics: The study of sorption speed and mechanisms. The pseudo-second-order kinetic model
(t/qₜ = 1/k₂qₑ² + t/qₑ)
best described uranium uptake, proving chemisorption – chemical bond formation between uranium and DPSB’s functional groups – controlled the process rate.
Thermodynamics: Analysis of how temperature influences sorption. Uranium removal increased from 70% at 25°C to 76% at 55°C, revealing an endothermic process where heat provides energy for uranium ions to bind more effectively with DPSB sites.
Endothermic Process: A reaction requiring heat absorption to proceed. Like dissolving salt in water, uranium sorption on DPSB works better at higher temperatures because thermal energy helps uranium ions overcome activation barriers to bond with the biomass.
Langmuir Isotherm: A model assuming uranium forms a perfect single molecular layer on DPSB’s homogeneous surface. The linear equation
Cₑ/qₑ = 1/(qₘₐₓb) + Cₑ/qₘₐₓ fit low-concentration data well,
where qₘₐₓ is maximum capacity and b reflects binding strength.
Freundlich Isotherm: A model for heterogeneous surfaces where uranium binds with varying intensities across different DPSB sites. The logarithmic equation ln
qₑ = ln K_F + (1/n)ln
Cₑ worked better at high concentrations, with K_F indicating capacity and 1/n showing favorability.
Chemisorption: Chemical bonding between uranium and DPSB’s functional groups (-OH, -COOH). Unlike weak physical adsorption, these strong bonds were confirmed by the pseudo-second-order model’s excellent fit (R² > 0.99) and temperature-dependent behavior.
Equilibrium Time: Duration until sorption stabilizes. For DPSB, equilibrium occurred faster at higher temperatures (60 min at 55°C vs. 90 min at 25°C) because heat accelerated uranium ion movement and binding site activation.
Activated Carbon: A highly porous, expensive adsorbent compared in studies to DPSB. While effective for uranium removal, its production requires energy-intensive processes, making biomass like DPSB a more sustainable alternative.
Functional Groups: Specific atomic arrangements (like -OH hydroxyl or -COOH carboxyl) on DPSB that chemically interact with uranium. These groups act like molecular “hands” that grab and hold uranium ions through coordination bonds.
Holocellulose: The fibrous framework of plant cell walls comprising cellulose and hemicellulose. DPSB’s 75% holocellulose content provides abundant binding sites, explaining its high uranium adsorption capacity compared to synthetic materials.
Arsenazo III: A purple dye forming colored complexes with uranium for concentration measurement. When added to samples, its color intensity changes proportionally to uranium amount, allowing precise spectrophotometric quantification.
Intra-Particle Diffusion: The slow process where uranium ions migrate into DPSB’s tiny pores after initial surface binding. Multi-stage kinetic plots revealed this as the rate-limiting step at higher uranium concentrations.
Van’t Hoff Equation: ln K = -ΔH°/RT + ΔS°/R relates temperature (T) to equilibrium constant (K). The positive ΔH° (10.8 kJ/mol) confirmed endothermic sorption, while positive ΔS° (27.6 J/mol·K) showed increased molecular randomness during uranium binding.
Gibbs Free Energy (ΔG°): A spontaneity indicator where negative values (-2.6 to -1.8 kJ/mol in this study) confirm uranium sorption occurs naturally without external energy input. More negative ΔG° at higher temperatures showed improved spontaneity.
Pseudo-First-Order Model: A less accurate kinetic alternative (R² < 0.81) suggesting physical forces alone couldn’t explain uranium uptake. Its poor fit reinforced that chemisorption dominated the process.
Dosage (S): The DPSB amount per water volume (g/L), calculated as S = m/v (mass/volume). While higher dosages increase uranium removal, the study optimized at 2 g/L to balance efficiency and material conservation.
Percentage Removal: The cleanup efficiency formula.
%Removal = (Cᵢ – Cₑ)/Cᵢ × 100%.
DPSB achieved 76% maximum removal, comparable to conventional methods but with lower costs and environmental impact.
Heterogeneous Surface: DPSB’s irregular texture with varied binding site energies. This explained why the Freundlich model (for uneven surfaces) outperformed Langmuir at high uranium concentrations where multiple adsorption mechanisms coexisted.
Reference:
Al-Anber, M.A., Almazaydeh, H., Al-Momani, I.F. et al. Efficient uranium capture from water with date palm seed biomass: green remediation. Environ Sci Pollut Res (2025). https://doi.org/10.1007/s11356-025-36259-w
