Innovative Methods to Achieve Ultra-Low Coke Rate for Carbon-Neutral Blast Furnaces

The progressive decarbonization of the steel industry is being undertaken through the transformation of blast furnace operations, notably through the reduction of coke consumption. Lower coke rates may affect gas permeability in the cohesive zone, a viscous and impermeable layer formed by the softening and melting of iron-bearing materials. Controlling the cohesive zone, its shape, thickness, and permeability, is essential for efficient blast furnace performance. The choice of adapted raw materials, i.e. their softening and melting properties, is a straightforward way to control the cohesive zone and to increase permeability. This study investigates the melting behavior of iron ore pellets with varying chemical compositions (acidic vs. fluxed) under conditions representative of the cohesive zone. Pellets were pre-reduced using the BORIS® counter-current pilot up to 1000 °C under representative conditions of the blast furnace. Reduced pellets were then subjected to melting tests via differential thermal analysis (DTA) and quenching furnace experiments. These analyses make it possible to better understand the softening and melting behavior of pellets in a blast furnace and results show that basic pellets generate less liquid phase at high temperatures, improving mechanical properties and improved reductive gas distribution. This result also implies a deeper and thinner cohesive zone inside the blast furnace. Attention was paid to the microstructure of the iron ores as the deformation of reduced materials is triggered by the partial melting of pellets and the formation of primary slag. Results also indicate that thermodynamic modelling could be a suitable and rapid tool to anticipate the behavior of different pellets at the cohesive zone level of blast furnaces, though existing databases must be refined to better reflect real phase equilibria in commercial iron ores.

Pre-reduction of Iron Ore with Ammonia and Its Utilization to Reduce Coke Rate and CO2 Emission in the Blast Furnace

Hydrogen is rapidly emerging as a cornerstone of sustainableenergystrategies, and unlocking its full potential depends on innovativetechnologies that harness renewable raw materials. In this context,this study explores a promising route: hydrogen production using anABE (acetone–butanol–ethanol) mixture derived from thefermentation of various biomass substrates. A Ni/MgO-Al2O3 catalyst (20 wt % of NiO and 10 wt % of MgO) was preparedand compared with Ni/Al2O3 in ABE (3:6:1 massratio, 10% v/v) steam reforming at 400–600 °C. The MgO-promotedcatalyst demonstrated significantly enhanced activity due to its superiorNi dispersion and increased basicity. At 500 °C, the Ni/MgO-Al2O3 catalyst achieved 92% global ABE conversionand a hydrogen yield of 55% while maintaining stable performance over30 h on stream. Moreover, the coking rate was substantiallyreduced compared with that of Ni/Al2O3, andthe deposited carbon was less amorphous, indicating an improved resistanceto deactivation. These findings highlight Ni/MgO-Al2O3 as a promising catalyst for sustainable hydrogen productionfrom biomass-derived ABE mixtures.

This paper presents the results of an investigation into the catalytic activity and selectivity of rhodium-based catalysts supported on natural zeolite clinoptilolite from the Shankanai field (Kazakhstan) in the dehydrogenation of light alkanes from associated petroleum gas (APG). Three modifications of the catalyst have been studied: basic 1%Rh/HCpt, modified with tin 1%Rh/10%SnO/HCpt, and combined with additives of tin and potassium 1%Rh/10%SnO/5%K2O/HCpt. It has been shown that the addition of tin contributes to increased thermal stability and a decreased coking rate, while the addition of potassium suppresses side reactions (cracking and isomerization), increasing the selectivity for olefins. The highest yield of olefins (~30%) is achieved with the 1%Rh/10%SnO/5%K2O/HCpt catalyst in the presence of water vapor. Using scanning electron microscopy (SEM) and high-resolution transmission electron microscopy (HRTEM), improved distribution of active components and reduced catalyst deactivation have been confirmed. The obtained data demonstrate the potential of the developed systems for the efficient processing of APG and the selective synthesis of olefins.

This study presents a comprehensive and integrative approach to optimizing fuel consumption in blast furnace operations, with a focus on the interdependence of PCI–Coke fuel ratio, oxygen-enriched air injection, and precise control of the Raceway Adiabatic Flame Temperature (RAFT). Based on the principles of combustion thermodynamics, reduction kinetics, and gas flow through the burden, the work analyzes critical performance indicators such as coke reactivity (CRI), post-reaction strength (CSR), and mechanical properties (M40, M10). The influence of raw material granulometry, burden distribution, moisture, alkalis, and zinc is also evaluated. Findings confirm that maintaining optimal RAFT and high-quality burden conditions enhances energy efficiency, reduces coke rate, and ensures greater process stability, while offering a sustainable pathway for advanced blast furnace management.

Nonthermal Plasma‐Catalytic Dry Reforming of Methane in Parallel‐Plate Dielectric Barrier Discharge Reactor Using Mg‐Modified Ni Catalysts

As an important nonoil route for acquiring aromatics, the highly efficient conversion of methanol to aromatics over Zn/ZSM-5 zeolites remains an ongoing challenge. In this work, we developed a uniform loading approach of zinc and further combined it with a hollow capsule structure to design the high-performance Zn/ZSM-5 catalyst. The electrostatic assembly among EDTA3-, n-butylamine+ and negative silica-alumina gel gave rise to an "Inorganic-Organic Hybrid Sphere" in form of Na(l+m+n+3x)-(y+z)·{[(SiO)4Al-]l/(SiO-)m(n-butylamine+)y(EDTA3-)x(n-butylamine+)z(SiO-)n, which further transformed into mesoporous aluminosilicates sphere (MASS) through calcination. The characteristic of abundant mesopore guaranteed MASS fantastic ability to evenly incorporate Zn ingredient inside, and the resultant Zn/MASS further served as a "hard template" for the direct synthesis of Hollow Zn/ZSM-5 capsules, rather than after impregnation. When tested in the methanol-to-aromatics (MTA) process, the direct synthesis method not only facilitated the homogeneous dispersion of the Zn ingredient, but also benefited for the generation of more (ZnOH)+ sites and strengthened their synergism with zeolite acid for the superior aromatics selectivity (50.63%). Meanwhile, the hollow capsule structure increased the contact time of MTA intermediate products with the Zn/ZSM-5 shell, and it increased the coke-admitting capacity and suppressed the coke rate, which maintained quite an excellent stability (131 h). Therefore, the above combination of hollow capsule structure and uniform load of Zn ingredient brings forward a wide prospect to develop zeolite materials with excellent properties in catalysis.

Abstract Expandable graphite (EG) is widely used in rigid polyurethane (PU) foam (RPUF) as flame retardant, however, the mechanical properties of RPUF would deteriorate with the increase of its content. To alleviate this problem, PU‐coated EG (PUEG) is prepared by coating PU on the surface of EG via interface polymerization. PUEG is characterized by FTIR, XPS, and SEM. The results show that PUEG is successfully prepared. Compared with the RPUF add with the pure EG, the compressive strength and flame retardancy of the RPUF prepared by adding 15% PUEG have been improved to varying degrees. A 15% PUEG and 20% PUEG modify RPUFs obtained both UL‐94 V‐0 rating with LOI values of 29.7% and 31.2%, respectively. The improvement in the flame retardancy and compressive strength of RPUF is due to the good interfacial compatibility between the RPUF and PU on the surface of the EG and the increased coking rate of the EG, which accelerates the formation of the thermal barrier carbon layer. The preparation process of PUEG is simple and suitable for large‐scale production.

Favorable formation of needle-shaped NiAl2O4 phase over macroporous Ni/CexZr1-xO2–Al2O3 catalysts in one-pot preparation and coke-resistant catalytic performance in dry reforming of methane

Fluoride- and OSDA-free synthesis of ZSM-5 with controllable b-axis orientation: Insights into the role of medium alkalinity and seed induction

Enhancement of non-thermal plasma-catalytic CO2 reforming of CH4 using Ni/Mg–Al2O3 catalysts in a parallel plate dielectric barrier discharge reactor

An improved coking model for simulating reactive transport phenomena and coking behavior in sucrose hydrolysis

Process optimization, exergy analysis, and GHG emissions of ammonia production systems by gasification of high-sulfur petroleum coke with CO2 capture

Due to the high sulfur content of high sulfur petroleum coke, sulfur-containing gas will be produced in the production process, reducing product quality and other problems, resulting in increased production costs and equipment corrosion. How to reduce the sulfur content of high sulfur petroleum coke is of great significance to improve the utilization rate of high sulfur petroleum coke and the sustainable development of related industries. In this paper, the desulfurization of high sulfur petroleum coke was carried out by using the additive-assisted high-temperature calcination method. It was found that the desulfurization effect of different kinds of desulfurization additives was different, among which MO1, MC2, MC1 desulfurization effect was better, and the desulfurization rate could reach 68%, 58%, 56%. After compounding the three desulfurizers, the desulfurization rate can be up to 75%, and then the influence of calcination temperature and time on the desulfurization rate was investigated. Finally, the physicochemical properties of petroleum coke before and after desulfurization were analyzed by X RD, FT-IR.

A series of quaternary ammonium or phosphonium salts were applied as zeolite growth modifiers in the synthesis of hierarchical ZSM-5 zeolite. The results showed that the use of methyltriphenylphosphonium bromide (MTBBP) could yield nano-sized hierarchical ZSM-5 zeolite with a "rice crust" morphology feature, which demonstrates a better catalytic performance than other disinfect candidates. It was confirmed that the addition of MTBBP did not cause discernable adverse effects on the microstructures or acidities of ZSM-5, but it led to the creation of abundant meso- to marco- pores as a result of aligned tiny particle aggregations. Moreover, the generation of the special morphology was believed to be a result of the coordination and competition between MTBBP and Na+ cations. The as-synthesized hierarchical zeolite was loaded with Zn and utilized in the propane aromatization reaction, which displayed a prolonged lifetime (1430 min vs. 290 min compared with conventional ZSM-5) and an enhanced total turnover number that is four folds of the traditional one, owing to the attenuated hydride transfer reaction and slow coking rate. This work provides a new method to alter the morphological properties of zeolites with low-cost disinfectants, which is of great potential for industrial applications.

A series of Zn-modified HBeta (Zn/HBeta) catalysts were prepared via the wetness impregnation method with different zinc precursors such as ZnSO4·7H2O, ZnCl2, C4H6O4Zn·2H2O and Zn(NO3)2·6H2O, and their catalytic performance in the conversion of ethanol to propylene reaction was evaluated. Results indicate that the amount and strength distribution of the acid sites of the Zn/HBeta catalysts were easily tuned by employing different types of zinc precursors. More importantly, when the zinc species were introduced to the HBeta, the propylene yield was significantly enhanced, whereas the yields of ethylene and C2–C4 alkanes were remarkably suppressed. For the catalyst prepared by using the ZnCl2 precursor, a higher propylene yield of up to 43.4% for Zn/HBeta-C was achieved as a result of the moderate amount and strength distribution of acid sites. The average coking rate of the used Zn/HBeta catalysts strongly depended on the amount of total acid sites, especially the strong acid sites, i.e., the higher the amount of total acid sites of the catalyst, the greater the average coking rate. For the catalyst prepared by using the ZnSO4·7H2O precursor, Zn/HBeta-S exhibited a better stability even after depositing more coke, which was due to the higher amount of strong acid sites.

Hydrogen production by biogas reforming using Ni/MgO-Al2O3 catalysts

Alkaline earth metal modified La-Fe based perovskite enhances hydroxyl radicals for efficient coke cleaning

Blast furnace (BF) hydrogen-rich smelting is an important way for the green and low-carbon development of iron and steel industry. The injection volume of hydrogen-rich gas is limited due to the need for hearth activity, which is related to the stable and smooth operation of BF. In this study, the change of coke properties after hydrogen-rich smelting was summarized, the detailed evolution process of hearth activity after hydrogen-rich smelting was analyzed. The results show that: the pores on the surface of coke are enlarged after hydrogen-rich smelting. The gasification rate of coke with H2O is significantly higher than that of CO2 due to the lower activation energy and smaller molecular diameters of H2O and H2. The interlayer spacing of coke decreases and the stacking height further increases rapidly, the degree of coke graphitization is the highest after hydrogen-rich smelting. The weakening of carbon anisotropy is the fundamental reason for the increase in the degree of graphitization of coke. The strong gasification reaction causes the coke to lose a lot of carbon, and its matrix becomes loose and incomplete, so the strength after reaction decreases sharply. The wetting model is established to analyze changes in wettability. The rough surface of coke improves the wettability between slag iron and coke at high temperature. The good wettability makes it easier for slag iron to adhere to the surface of coke. The smoothness of slag iron passing through coke is reduced, the retention amount of liquid slag iron in coke layer increases. It leads to a decrease in hearth activity, the stable and smooth operation of BF is difficult to guarantee. This is the main issue limiting the injection volume of hydrogen-rich gas in BF.