Experimental methods in chemical engineering: specific surface area and pore size distribution measurements—BET, BJH, and DFT

The separation of hydrogen sulfide (H2S) from gas streams has significant economic and environmental repercussions for the oil and gas industries. The present work reviews H2S separation via nonreactive and reactive adsorption from various industrial gases, focusing on the most commonly used materials i.e., natural or synthetic zeolites, activated carbons, and metal oxides. In respect to cation-exchanged zeolites, attention should also be paid to parameters such as structural and performance regenerability, low adsorption temperatures, and thermal conductivities, in order to create more efficient materials in terms of H2S adsorption. Although in the literature it is reported that activated carbons can generally achieve higher adsorption capacities than zeolites and metal oxides, they exhibit poor regeneration potential. Future work should mainly focus on finding the optimum temperature, solvent concentration, and regeneration time in order to increase regeneration efficiency. Metal oxides have also been extensively used as adsorbents for hydrogen sulfide capture. Among these materials, ZnO and Cu–Zn–O have been studied the most, as they seem to offer improved H2S adsorption capacities. However, there is a clear lack of understanding in relation to the basic sulfidation mechanisms. The elucidation of these reaction mechanisms will be a toilsome but necessary undertaking in order to design materials with high regenerative capacity and structural reversibility.

https://www.mdpi.com/2073-4344/10/5/521/pdf

Removal of Hydrogen Sulfide From Various Industrial Gases: A Review of The Most Promising Adsorbing Materials

Pure hematite nanoparticles (HNPs) were successfully synthesized via the simple precipitation route by using ferric sulfate precursor and ammonium hydroxide (NH4OH) precipitant. The current study reports the effects of precursor concentrations, from 0.05 to 0.45 M, on the product size, morphology, crystallinity, and lumps formation. X-ray diffraction (XRD) data confirmed the synthesis of pristine HNPs having a rhombohedrally centered hexagonal structure. In addition, the particle size effect on the XRD peak shifting was studied and found to be consistent with the calculated size results by Scherer equation. Transmission electron microscopy revealed mixed polygonal and hexagonal morphologies with an average size of (16–44 nm) depending on the precursor concentration. Scanning electron microscopy depicts lots of agglomerations and lumps with increasing the precursor concentration. Raman spectra not only show the seven phonon modes of pristine hematite phase but also confirm the evolution of the crystal structure with concentration. Thermal analyses proved that the synthesized α-Fe2O3 products in the current work using 0.05 M precursor concentration are well crystallized at around ≈464 °C. Thus, current work presents smaller-sized HNPs crystallized at lower temperature ranges with different morphologies and higher probable vulnerable facets compared to previous studies. This will show improved properties and give rise to higher potentials for various applications. Furthermore, it verifies that the precursor nature is the key factor affecting both size and morphology, whereas, precursor concentration not only affects the particle size as reported previously but also crystallinity, morphology development, and lumps formation of the final product.

Improved size, morphology and crystallinity of hematite (α-Fe2O3) nanoparticles synthesized via the precipitation route using ferric sulfate precursor

This paper presents a review of recent research on direct upgrading of coal/biomass volatiles into aromatics by catalytic pyrolysis and syngas by gasification with catalytic steam reforming. Coal/b...

Catalytic Conversion of Coal and Biomass Volatiles: A Review

Biofiltration of hydrogen sulfide: Trends and challenges

Evaluation of the cycling performance of a sorbent for H2S removal and simulation of desulfurization-regeneration processes

Microwave effects on the structure of CeO2-doped zinc oxide sorbents for H2S removal

Ion Regulation of Hollow Nickel Cobalt Layered Double Hydroxide Nanocages Derived from ZIF-67 for High-Performance Supercapacitors

Effect of microwave irradiation on the preparation of iron oxide/arenaceous clay sorbent for hot coal gas desulfurization

Mesoporous Zn-Fe-based binary metal oxide sorbent with sheet-shaped morphology: Synthesis and application for highly efficient desulfurization of hot coal gas

Mengmeng Wu

Papers

Evaluation of the cycling performance of a sorbent for H2S removal and simulation of desulfurization-regeneration processes

Microwave effects on the structure of CeO2-doped zinc oxide sorbents for H2S removal

Ion Regulation of Hollow Nickel Cobalt Layered Double Hydroxide Nanocages Derived from ZIF-67 for High-Performance Supercapacitors

Effect of microwave irradiation on the preparation of iron oxide/arenaceous clay sorbent for hot coal gas desulfurization

Mesoporous Zn-Fe-based binary metal oxide sorbent with sheet-shaped morphology: Synthesis and application for highly efficient desulfurization of hot coal gas