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.

Titanium-doped indium tin oxide thin films were synthesized via a sol-gel spin coating process. Surface chemical bonding states and mechanical properties have been investigated as a function of titanium content (2 and 4 at%) and annealing temperature ranging from 400 to 600 °C with increments of 100 °C. Raman analysis was performed to study the phonon vibrations for the prepared samples and the results revealed the existence of ITO vibrational modes. The elemental compositions, bonding states and binding energies of the film materials were investigated using X-ray photoelectron spectroscopy (XPS) technique. The XPS results indicated that the ratio of the metallic elements (In, Sn, Ti) to the oxygen on the surface of the thin film coatings decreased due to the increase of the oxide layer on the surface of the thin films. Also, by increasing the annealing temperature up to 600 °C, the Ti 2p and Cl 2p signals were no longer detected for both 2 and 4 at% Ti contents, respectively, due to the thicker surface oxidation layer. Mechanical properties of the synthesized films were also evaluated using a nanoindentation process. Variations in the hardness (H) and the elastic modulus (E) were observed with different Ti at% and annealing temperatures. The hardness is within the range of 6.3–6.6 GPa and 6.7–6.8 GPa for 2 and 4 at% Ti content samples, respectively, while the elastic modulus is within the ranges of 137–143 and 139–143 GPa for 2 at% and 4 at% Ti contents samples, respectively. A combination of the highest H and E were achieved in the sample of 4% Ti content annealed at 600 °C. Furthermore, the H/E ratio ranges from 4.5 × 10−2 to 5.0 × 10−2 which reflects a reasonable level of wear resistance

In the present study, the ability for novel carbon microspheres (CMs) derived from date palm (Phoenix dactylifera) biomass using a hydrothermal carbonization (HTC) process and activated using phosphoric acid to remove methylene blue dye was investigated. Three types of palm-based wastes (seeds, leaflet, and inedible crystallized date palm molasses) were used and converted to CMs via the HTC process. The prepared samples were then activated using phosphoric acid via the incipient wetness impregnation method. The CMs samples before and after activation were analyzed using scanning electron microscopy (SEM), elemental analysis and scanning (CHNS), and the Fourier transform infrared (FTIR) and Brunauer–Emmet–Teller (BET) methods. The samples exhibited high BET surface areas after activation (1584 m²/g). The methylene blue adsorption results showed good fitting to the Langmuir, Fruendlich, and Temkin isotherm models for all activated samples. The maximum adsorption capacity achieved was 409.84 mg/g for activated CM obtained from the palm date molasses, indicating its high potential for application as a dye-based adsorption material.

This study investigates the extraction of cellulose from Saudi Arabia-based date palm biomass utilizing a natural deep eutectic solvent (NaDES) integrated with a microwave-assisted process. A comprehensive life cycle assessment (LCA) was conducted in accordance with the ISO 14040 standard, encompassing four key stages: goal and scope definition, life cycle inventory analysis (LCI), life cycle impact assessment (LCIA) and interpretation. The analysis was confined to a gate-to-gate boundary in which two impact assessment methods, namely, ReCiPe Midpoint (H) 2016 and ILCD 2011 Midpoint, were used to assess the environmental impacts. The OpenLCA software (version 2.1.1) with the European Life Cycle Database 3.2 (ELCD 3.2) was used in the study. The ReCiPe method identified impact categories such as fossil resource scarcity, terrestrial ecotoxicity, freshwater ecotoxicity, water consumption, human carcinogenic toxicity and marine ecotoxicity. Conversely, the ILCD method identified freshwater ecotoxicity, water resource depletion, mineral, fossil and resource depletion, human toxicity and cancer effects. The results indicate that freshwater ecotoxicity presents the most substantial environmental impact across both assessment methods, surpassing other categories. Fossil resource scarcity, even though originally appearing impactful, demonstrated a relatively lower normalized score compared to freshwater ecotoxicity. Terrestrial ecotoxicity and water consumption were found to be negligible in their impact. Our findings provide important insights into sustainable material science and waste management, affording potential applications for biomass utilization in the Gulf region.

The removal of lead metals from wastewater was carried out with carbon microspheres (CMs) prepared from date palm leaflets using a hydrothermal carbonization process (HTC). The prepared CMs were subsequently activated with phosphoric acid using the incipient wetness impregnation method. The prepared sample had a low Brunauer–Emmet–Teller (BET) surface area of 2.21 m²·g⁻¹, which increased substantially to 808 m²·g⁻¹ after the activation process. Various characterization techniques, such as scanning electron microscopy, BET analysis, Fourier transform infrared, and elemental analysis (CHNS), were used to evaluate the morphological structure and physico-chemical properties of the CMs before and after activation. The increase in surface area is an indicator of the activation process, which enhances the absorption properties of the material. The results demonstrated that the activated CMs had a notable adsorption capacity, with a maximum adsorption capacity of 136 mg·g⁻¹ for lead (II) ions. This finding suggests that the activated CMs are highly effective in removing lead pollutants from water. This research underscores the promise of utilizing activated carbon materials extracted from palm leaflets as an eco-friendly method with high potential for water purification, specifically in eliminating heavy metal pollutants, particularly lead (II), contributing to sustainability through biomass reuse.