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The purpose of the current study is to identify the potential of energy-efficient hydrogen (H 2) production from date seeds as biomass via steam gasification process along with heat integration in Gulf countries. A reaction kinetics model has been established for steam gasification with in-situ carbon dioxide (CO 2) capture of date seeds using MATLAB software. The kinetics of reactions involved in the gasification process was calculated using the optimization parameters fitting approach. The heat integration model has been developed via mixed integer nonlinear programming (MINLP) in MATLAB. In the parametric study, temperature and steam/biomass ratio considered their impact on syngas composition and energy recovery. Results showed that both variables have a strong positive effect on H 2 production and depicted maximum production of 68 mol% at a temperature of 750 °C with steam/biomass ratio of 1.2. Methane (CH 4) and CO 2 production were low in the product gas, which showed the activity of water gas shift reaction, methanation reaction, and carbonation reaction. Utilization of waste heat via process heat integration within the system reduced system's external heat load. More than 70% of energy recovered, which could be utilized for gasification and steam production. Energy analysis and process heat integration proved a prospective approach for energy-efficient and sustainable hydrogen production from date seeds. [Display omitted] • Reaction kinetic model developed for the steam gasification of date seeds. • Kinetics of reactions calculated using parameters fitting approach. • Heat integration model developed via mixed-integer non-linear programming. • Energy analysis and process heat integration carried out for the heat recovery. [ABSTRACT FROM AUTHOR]

[Display omitted] • Thermal degradation behavior, kinetic and thermodynamic analyses of surface fibers of date palm. • Kinetic analysis was performed on the devolatilization region using the Coats–Redfern model–fitting method. • Surface fibers pyrolysis governed by two diffusion models: one–way transport and Valensi equation. • E a and A were estimated to be 91.40 kJ/mol and 1.59 × 103 –29.39 × 103 min−1, respectively. The potential of the least-exploited date pam waste was presented as feedstock for bio-oil production. The surface fibers of the date palm are widely available as waste material in the Gulf region, the Middle East, and Africa. Chemical composition analysis and physiochemical characterization showed that surface fibers are valuable feedstock for energy production. Surface fibers were analyzed thermogravimetrically at different heating rates (10, 20, and 30 °C /min) in an inert atmosphere. Decomposition was carried out in three stages: dehydration, devolatilization, and solid combustion. Kinetic analysis was performed on the devolatilization region using the Coats–Redfern model–fitting method using twenty–one reaction mechanisms from four different solid-state reaction mechanisms. Two diffusion models: one–way transport (g(x) = α2) and Valensi equation (g(x) = α+(1-α) × ln(1-α)) showed the highest regression coefficient (R2) with the experimental data. The activation energy (E a) and the pre-exponential factor (A) was estimated to be 91.40 kJ/mol and 1.59 × 103 –29.39 × 103 min−1, respectively. The kinetic parameters were found to be dependent on the heating rate. The surface fibers' thermodynamic parameters ΔH, ΔG, and ΔS were 80–97, 151–164, and −0.17- −0.18 kJ/mol, respectively. This indicates that the pyrolysis of surface fibers is endothermal and not spontaneous. Since there is not much experimental work on the pyrolysis of surface fibers available in the literature, the reported results are crucial for designing the pyrolysis process. [ABSTRACT FROM AUTHOR]