A comparative study of the removal of o-xylene from gas streams using mesoporous silicas and their silica supported sulfuric acids

Gao, Kaiyin; Ma, Mengze; Liu, Yuheng; Ma, Zhen

doi:10.1016/j.jhazmat.2020.124965

Cited by 16 publications

(14 citation statements)

References 60 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Especially at 700 °C, the o -xylene breakthrough from the HIO bed remained unseen until 54 h, and the process curve was also different as compared to the curves acquired at lower temperatures ( Figure 2 b), thus, implying that HIO might have possessed super capacity (more than 691 mg g[Fe] −1 ) and unique reaction mechanism for removing o -xylene, which need to be studied further. Comparing Q B of HIO for removing o -xylene with other materials already reported in the literature [ 9 , 10 , 11 , 12 ], the value obtained here was higher.…”

Section: Resultssupporting

confidence: 40%

“…Therefore, the development of new technologies to prevent the VOC contamination is currently of significant interest [ 5 , 6 , 7 , 8 ]. Among these, the processes that can enable the achievement of VOC resource utilization are a key to move towards sustainability; thus, these have received an increasing attention in recent years [ 9 , 10 , 11 , 12 , 13 , 14 ]. Considering that the mainstream technologies for VOCs elimination such as catalytic oxidation and thermal combustion are based on VOCs oxidation reactions, it is suspected that VOCs have a potential as reducing agents in the iron-making process from iron oxide ores.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Utilization of Hematite Particles for Economical Removal of o-xylene in a High-Temperature Gas-Solid Reactor

Zhao

Qian

et al. 2022

Molecules

Self Cite

View full text Add to dashboard Cite

To establish a novel approach for VOCs resource utilization, coupled o-xylene oxidation and hematite reduction was investigated in this study in a high-temperature gas-solid reactor in the temperature range 300–700 °C. As the o-xylene-containing inert gas (N2) stream traveled through the hematite particle bed, its reaction behavior was determined in programmed heating and constant temperature modes. Consequently, the effect of bed temperature, flow rate and o-xylene inlet concentration on both o-xylene removal performance and degree of hematite reduction was studied. The raw hematite and solid products were analyzed by TGA, XRF, XRD and SEM-EDS. The results showed that a temperature above 300 °C was required to completely eliminate o-xylene by hematite, and both o-xylene removal capacity and degree of hematite reduction at 5% breakthrough points enhanced on increasing the temperature and decreasing the flow rate. The increment in temperature from 300 °C to 700 °C led to a gradual reduction of Fe2O3 to Fe3O4, FeO and metallic iron. Thus, this study provides a novel, economic and promising technology for treating the VOC pollutants.

show abstract

Section: Resultssupporting

confidence: 40%

Section: Introductionmentioning

confidence: 99%

Utilization of Hematite Particles for Economical Removal of o-xylene in a High-Temperature Gas-Solid Reactor

Zhao

Qian

et al. 2022

Molecules

Self Cite

View full text Add to dashboard Cite

show abstract

“…However, as can be seen from Figure 1 and Table 1 (the TG curves and the calculated amount of the P-and C-state H 2 SO 4 for the SSA(E)-4 and SSA(W)-4), the proportion of the C-state H 2 SO 4 in SSA(E)-4 was higher than that in SSA(W)-4, indicating that the features of the solvents affected the anchoring states of sulfuric acid in SG support. As suggested in our previous studies [22,23], the C-state H 2 SO 4 , defined as the chemically bonded sulfuric acid, was formed by the condensation of silanol groups of SG surface and sulfuric acid molecules, and it was higher than the P-state counterpart (defined as the physisorbed sulfuric acid) in the bond strength. It was speculated that the use of ethyl acetate as the impregnation medium might promote the condensation of silanol groups and H 2 SO 4 molecules since it is a weakly polar solvent (dipole moment µ = 4.40, dielectric constant ε = 6.02) without hydroxyl groups compared with water (µ = 1.84, ε = 80.10) [24].…”

Section: Loading Amount and Anchoring States Of Sulfuric Acid In The ...mentioning

confidence: 61%

“…It is speculated that the observed adsorption superiority of SSA(E)-4 towards o-xylene was closely associated with a higher amount of the C-state H 2 SO 4 as compared to SSA(E)-4. Gao et al [23] suggested that the C-state sulfuric acid had higher thermal stability than the P-state counterpart, thereby leading to a superior performance in SSA(E)-4 for removing o-xylene from the gas stream.…”

Section: Effect Of Temperature On Adsorption Of Ssa(e)-4 and Ssa(w)-4...mentioning

confidence: 99%

Influence of Impregnation Medium on the Adsorptive Performance of Silica Sulfuric Acid for the Removal of Gaseous o-Xylene: Comparison on Ethyl Acetate and Water

Zhao

Ma²,

Qian³

et al. 2022

Catalysts

Self Cite

View full text Add to dashboard Cite

Silica supported sulfuric acid (SSA) has been demonstrated to be capable of effectively removing phenyl VOCs through the reaction-type adsorption mechanism. The effects of the solvent (water, ethyl acetate) used to impregnate silica gel with H2SO4 solution in order to prepare SSA adsorbents have been studied. As-prepared two series SSA(E)-x and SSA(W)-x materials (x = 1, 2, 3, 4) were characterized by TG, SEM/EDS and N2 adsorption/desorption techniques, and their breakthrough adsorption performances were evaluated from experimental and theoretical aspects. The results showed that the H2SO4 loading amounts were 2.8, 4.0, 4.8 and 5.6 mmol g−1 respectively for both SSA(E)-x and SSA(W)-x when x equaled 1, 2, 3, 4. Among them, SSA(E)-4 was found to have a higher proportion of the C-state H2SO4 than SSA(W)-4. Both SSA(E)-x and SSA(W)-x exhibited significant removal capacity of gaseous o-xylene. The reactive temperature regions were determined to be 120–170 °C for SSA(E)-4 and 120–160 °C for SSA(W)-4 with a common optimum point of 160 °C. Both SSA(E)-x and SSA(W)-x adsorbents exhibited excellent recyclability and reuse performance. Further, the series SSA(E)-x materials outperformed the series SSA(W)-x on all adsorption performance metrics, suggesting that ethyl acetate is a preferred solvent for preparing the SSA materials in phenyl VOCs removal application.

show abstract

“…The data obtained from this model can be used to calculate the theoretical breakthrough time (t B,th , min) and theoretical breakthrough adsorption capacity (Q B,th , mg g −1 ). The Equation (2) for this model is [37]:…”

Section: Model Of the Breakthrough Curvesmentioning

confidence: 99%

Vitamin C-Assisted Fabrication of Aerogels from Industrial Graphene Oxide for Gaseous Hexamethyldisiloxane Adsorption

Zheng

Hou

et al. 2021

Applied Sciences

Self Cite

View full text Add to dashboard Cite

Volatile methyl siloxanes (VMSs) as a trace impurity in biogas decreases its energy utilization, and thus need to be removed. In this paper, a one-step hydrothermal reduction was performed to produce three-dimensional reduced graphene oxide aerogels (rGOAs) using industrial-grade graphene oxide (IGGO) as raw material and vitamin C (VC) as a reductant to facilitate the fabrication of rGOAs. The synthesis of rGOAs was a simple, green, and energy-efficient process. The developed rGOAs were characterized using the Brunauer–Emmett–Teller method, Raman spectrometry, scanning electron microscopy, Fourier-transform infrared spectroscopy, X-ray diffraction measurements and contact angle. The results obtained showed that rGOA-1 with a VC/IGGO ratio of 1/1 (m/m) exhibited a hierarchical porous structure and super-hydrophobicity, yielding a high specific surface area (137.9 m2 g−1) and superior water contact angle (143.8°). The breakthrough adsorption capacity of rGOA-1 for hexamethyldisiloxane (L2, a VMS model) was 11 times higher than that of IGGO. Low inlet concentration and bed temperature were considered beneficial for the L2 adsorption. Interestingly, rGOA-1 was less sensitive to water, and it was readily regenerated for reuse by annealing at 80 °C. The rGOAs have been demonstrated to have great potential for the removal of siloxanes from biogas.

show abstract

A comparative study of the removal of o-xylene from gas streams using mesoporous silicas and their silica supported sulfuric acids

Cited by 16 publications

References 60 publications

Utilization of Hematite Particles for Economical Removal of o-xylene in a High-Temperature Gas-Solid Reactor

Utilization of Hematite Particles for Economical Removal of o-xylene in a High-Temperature Gas-Solid Reactor

Influence of Impregnation Medium on the Adsorptive Performance of Silica Sulfuric Acid for the Removal of Gaseous o-Xylene: Comparison on Ethyl Acetate and Water

Vitamin C-Assisted Fabrication of Aerogels from Industrial Graphene Oxide for Gaseous Hexamethyldisiloxane Adsorption

Contact Info

Product

Resources

About