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Exploring the new non-edible source of biomass for green energy production becomes extremely important with the increase in global energy crises. The primary objective of this work is to evaluate the potential of halophyte (Phragmites australis), a salt-tolerant plant for syngas production, and provide it as a promising alternative biofuel for sustainable energy production. This study is based on the steady-state chemical equilibrium model simulation of steam gasification of halophyte biomass (Phragmites australis) with CO2capture through sorbent (CaO) using ASPEN PLUS®. The simulation model works on the principle of Gibbs free energy minimization. The operating parameters such as temperature, steam to biomass ratio (STBR), and CaO/biomass ratio have been varied over a wide range. The effect of high heating value (HHV), low heating value (LHV), H2/CO, carbon conversion efficiency (CCE), and cold gas efficiency (CGE) has been investigated for syngas production. The results showed that with the increase of temperature from 600 to 700 °C, H2concentration increased from 69.52 to 75.16 vol %, respectively. A reduction in CO2concentration from 16.91 to 5.4 vol % is observed by increasing the CaO/biomass ratio from 0.1 to 0.9. It has been observed that the product gas hydrogen yield rises with increased temperature. At an optimum temperature of 700 °C with an STBR of 0.4 and CaO/biomass ratio of 1.42, the maximum hydrogen yield is 75.16 vol % with a minimum CO2content of 5.4 vol %. At these optimum conditions, the values of HHV, LHV, CCE, and CGE are 13.32 MJ/Nm3, 15.20 MJ/Nm3, 42.91%, and 78.63%, respectively. In addition, the developed model is validated against published literature data, and the results show good agreement with the published data. The relative error for hydrogen and carbon monoxide is within limits, i.e., 3.02% and 0.67% at 700 °C, 5.30% and 3.61% at 600 °C, and 10.62% and 35.03% at 500 °C, respectively, which validates the proposed model. It can be concluded that the sorption-based biomass gasification process is a promising technique for greener syngas production.

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The current work is based on the simulation modeling of steam gasification of palm kernel shell (PKS) with CO2capture through sorbent (CaO) using Aspen plus. The simulation model is developed using a Gibbs free energy minimization method. The objective of this work is to investigate the effect of key parameters like temperature, steam/biomass ratio, and CaO/biomass ratio on syngas yield. The system performance was also evaluated through carbon conversion efficiency, cold gas efficiency and gasification efficiency, lower and higher heating values by varying the gasification temperature, steam/biomass ratio, and CaO/biomass ratio. The H2concentration increased from 65 to 79.32 vol % with the increase of temperature from 650 to 700 °C. The CO2content was reduced from 20 to 5.32 vol % by increase in CaO/biomass ratio from 0.5 to 1.42. The maximum hydrogen content predicted is 79.32 vol %, and the minimum CO2content is 5.42 vol % found at operating parameters including a temperature of 700 °C, steam/biomass ratio of 1.5, and CaO/biomass ratio of 1.42. In addition the simulation model predicted results were compared with experimental data obtained from the experimental set up used in the simulation.

In the ongoing effort to reduce carbon emissions on a worldwide scale, green hydrogen, which is generated through environmentally responsible processes, has emerged as a significant driving force. As the demand for clean energy continues to rise, it is becoming increasingly important to have a solid understanding of the technological and economic elements of modern techniques of producing green hydrogen. In the context of green hydrogen generation understanding green hydrogen production's techno-economic features is necessary to reduce carbon emissions and transition to a low-carbon economy. associated with breakthroughs in technology, the present study examines the most fascinating and relevant aspects of techno-economic analysis. Despite challenges, green hydrogen can help the world move to a cleaner, more sustainable energy future with solid analytical frameworks and legislation.

•Absorption refrigeration system (ARS) can utilize waste heat to produce cooling.•Organic Rankine cycle (ORC) can utilize waste heat to produce power.•A novel configuration employing ARS and ORC is proposed for waste heat recovery .•Thermo-economic analysis and parametric study is performed.•The optimized configuration possessed better thermodynamic and economic performance.

The objective of this research work was to utilize machine learning tools for predicting the yield and hydrogen contents of bio-oil (H-bio-oil) based on biomass compositions of feedstock and pyrolysis conditions. In this regard, multiple linear regression (MLR) and random forest (RF) method was successfully applied and compared. The results verified RF’s larger feasibility than MLR for predicting bio-oil yield and H-bio-oil. Moreover, the profound information behind the model was extracted. The compositions of feedstock exerted more influences on both yield (60%) and H-bio-oil (77%). Besides, the proximate analysis information was preferable to determine yield, which was inverse for H-bio-oil. The modes of each variable affecting yield and H-bio-oil were described by partial dependence analysis. This research provided a reference for upgrading the bio-oil and extended the knowledge into biomass pyrolysis process.

This study focuses on the thermal, morphological and physical properties of spray-dried chicory root inulin using a thermogravimetric analyzer, environmental scanning electron microscopy, X-ray diffractogram and modulated differential scanning calorimetry. Different spray-drying conditions were investigated by varying inlet temperature, outlet temperature and aspirator speed. The starting material was semicrystalline. A feed temperature of 95°C was employed, which produced a completely transparent solution for spray drying. At that particular temperature, the powder samples obtained were entirely amorphous and morphology resembled each other except for higher solid content. The low glass transition temperature (Tg) (106.83°C) was evident by treating low-molecular-weight samples, whereas high-molecular-weight samples exhibited high Tg(125.81°C). The semicrystalline samples due to the high concentration and milky dispersion exhibited high decomposition temperature. The feed temperature, molecular weight and concentration of the samples tend to have a significant effect on the properties of spray-dried inulin.

This study investigates the co-pyrolysis of sugar cane bagasse (B), sewage sludge (S), and their blends of different proportions (100% B, 70% B/30% S, 50% B/50% S, 30% B/70% S, and 100% S) through thermogravimetric analysis–differential thermal analysis at 20 °C/min. The purpose of this study to assess the synergistic effect of the addition of sugar cane bagasse into sewage sludge and investigate the co-pyrolysis process kinetics and thermodynamics by employing five major reaction mechanisms with 17 models using the Coats and Redfern method. The kinetic result indicates a synergistic effect of bagasse and sewage sludge. The active co-pyrolysis zone was divided into two reaction zones: zone I (200–400 °C) and zone II (400–600 °C). In both zones, 100% bagasse has the highest Ea(F1–F3, 20.77–106.54 kJ/mol; D1–D4, 1.59–89.27 kJ/mol; N1–N4, 2.33–43.69 kJ/mol; and P0.5–Pi, 2.15–39.88 kJ/mol) and A(F1–F3, 2.22 × 10+2–6.4 × 10+10min–1; D1–D4, 3.20 × 10+2–3.72 × 10+2min–1; N1–N4, 2.33 × 10+2–3.20 × 10+2min–1; and P0.5–Pi, 2.33 × 10+2–3.20 × 10+2min–1) compared to 100% sewage sludge Ea(F1–F3, 6.20–51.06 kJ/mol; D1–D4, 1.85–68.01 kJ/mol; N1–N4, 2.07–32.06 kJ/mol; and P0.5–Pi, 0.91–29.25 kJ/mol) and A(F1–F3, 2.66 × 10+2–4.0 × 10+2min–1; D1–D4, 2.66 × 10+2–4.32 × 10+2min–1; N1–N4, 2.06 × 10+2–2.66 × 10+2min–1; and P0.5–Pi, 2.06 × 10+2–2.66 × 10+2min–1) for all reaction mechanisms. Among blends in zones I and II, 70% B/30% S showed the highest Ea(F1–F3, 17.15–82.77 kJ/mol; D1–D4, 4.34–89.15 kJ/mol; N1–N4, 1.83–42.44 kJ/mol; and P0.5–Pi, 2.27–39.82 kJ/mol) and A(F1–F3, 2.24 × 10+2–3.40 × 10+2min–1; D1–D4, 4.76 × 10+2–12 × 10+5min–1; N1–N4, 2.32 × 10+2–2.43 × 10+2min–1; and P0.5–Pi, 2.32 × 10+2–2.34 × 10+2min–1) compared to all other blends for all reaction mechanisms.

This study investigates the co-pyrolysis behavior of bituminous coal (100%BC), algae consortium (100%AC), and their blends at various blending ratios. The pure and coal-biomass blends were characterized using CHN-S, GCV, and FTIR analysis. Whereas, the co-pyrolysis of blends were performed in a TGA. The deviation between the experimental and calculated values of weight loss (WL%), the residue left (RL%), and the maximum rate of weight loss (wt%/min) was used to calculate the synergistic effects. Kinetic parameters were investigated using the Coats-Redfern integral method through eighteen (18) reaction mechanistic models. The activation energy (Ea) for 100%BC was 85.04 kJ/mol through the F3 model, whilst for 100%AC showed 78.22 kJ/mol using the D3 model. Thermodynamic parameters such as Enthalpy (∆H) and Gibbs free energy (∆G) showed positive values, while Entropy (∆S) was negative for each coal-biomass blend. The catalytic co-pyrolysis of the optimum blend (20BCE-80AC) was studied using CeO2loaded MgNiAl (CeO2@MNA) as a multifunctional catalyst. The increased WL% displayed a positive effect toward a higher yield of volatile matter. Eaof the optimum blend in co-pyrolysis was further reduced through catalytic co-pyrolysis and Eain the first and second stages was 72.48 kJ/mol and 13.76 kJ/mol, while 3 wt% catalyst loading further reduced its Eain both stages to 67.82 kJ/mol and 41.21 kJ/mol. The use of CeO2@MNA at 3 wt% loading showed a reduction in the peak devolatilization temperature (Tp) of the optimum blend substantially increasing the reaction rate, and reducing the Earequired for the decomposition process.

Rice husk is considered as a massive agricultural lignocellulosic biomass residue for the production of bio-based fuels and chemicals products. The purpose of this study is to investigate the physiochemical properties of the pyrolysis-oil derived from wet and dried rice husk fast pyrolysis process. The experiments were performed in a drop type fixed-bed pyrolyzer at the pyrolysis temperature of 350 to 600 °C. The products, char, pyrolysis-oil and gas, yield are investigated. The pyrolysis-oil derived from dried rice husk contained higher Carbon and Hydrogen and less oxygen contents than the pyrolysis-oil obtained from wet rice husk. FT-IR results showed the oxygenated compounds present in both pyrolysis-oil. The pyrolysis oil from dried rice husk has higher concentration of hydrocarbons as compared to wet rice husk pyrolysis-oil. The dried rice husk pyrolysis-oil produced more phenols and less carboxylic acid as compared to wet rice husk pyrolysis-oil at 500 °C. More volatile released in dried rice husk conversion produced more volatile compounds. These findings suggest that the original moisture present in biomass samples is the major influencing parameter on the thermal degradation of biomass during fast pyrolysis process.

The waste-derived CaO promoted Mg-Ni-Al (MNA) based hydrotalcite hybrid catalysts were synthesized by co-precipitation and wet impregnation method and tested for sorption enhanced steam methane reforming (SESMR) for hydrogen (H2) production. The catalysts were characterized using X-ray diffractometer (XRD), Field emission scanning electron miscroscopy (FESEM), Scanning electron microscopy (SEM) with energy dispersive X-ray (EDX) analysis, Brauner Emmett teller (BET), laser particle size analyzer, Temperature programmed reduction (TPR), Thermogravimetric analysis (TGA), and Fourier transform infrared spectroscopy (FTIR). Various CaO loadings varying from 0-15% into the MNA-based hydrotalcite catalysts (MNA HTc) were assessed for SESMR in a fixed bed reactor. The results revealed that 10% CaO@MNA exhibited the best performance in terms of a longer pre-breakthrough period with respect to other compositions. The CH4fraction, H2purity, and CO2production in the absence of CaO were marked at 60%, 55%, and 14% respectively. However, the CH4fraction and H2purity increased to 77% and 80%, while CO2decreased to 3% in the pre-breakthrough period for 10% CaO @ MNA at 650 °C, WHSV 2000 mL CH4g-1h-1and S/C of 2.0. The nanocomposite 10%CaO@MNA was tested over three consecutive SESMR at 650 °C to analyze its regeneration capacity. The hybrid catalyst was also tested at various temperatures from 650-850 °C to investigate the effect of CaO sorbent. It was found that elevated temperatures >750 °C likely reduced the carbonation reaction and shifted the technique to SMR. The spent catalyst exhibited negligible carbon formation on the catalyst surface. The catalytic performance of the reported catalyst-sorbent system is encouraging for further regeneration studies for SMR and other reforming techniques.

In this work, the biomass fly ash (BFA) was investigated as a potential catalyst for the thermo-catalytic decomposition of methane and attractive approach for hydrogen (H2) production. The BFA based CeO2nanowires promoted cobalt catalyst was synthesized for catalytic methane (CH4) decomposition and was tested in a fixed bed reactor. The physicochemical properties of the catalyst were investigated using various techniques such as X-ray powder diffraction, scanning electron microscopy, energy-dispersive X-ray spectroscopy, thermal gravimetric analysis, and Fourier transformed infrared. The pure crystalline micro-flake BFA was modified using synthesized CeO2nanowires and the resulted micro flakes cross-linked with nanowires shown thermal stability up to 900 °C. The high stability of the catalyst makes it suitable for the thermal catalytic decomposition of methane. The activity of the catalyst was tested at 850 °C to analyze the H2production and CH4conversion. The obtained results revealed that support and promoter exhibit a strong impact on the CH4conversion and H2yield in catalyst screening tests. A maximum conversion of 71% for CH4with 44.9% H2yield was recorded for 34 h on stream activity while using 5% Co/CeO2-BFA as the catalyst. While BFA and Co-BFA as catalyst showed 36% and 47% conversion of CH4, respectively which indicates that the addition of promoter shows an increase in values of both conversion of CH4and H2yield. Compared to traditional catalyst support, the use of waste-sourced catalyst support for CH4decomposition provides a greener and more economical route for H2production.