scholarly journals Deactivation Model Study of High Temperature H2S Wet-Desulfurization by Using ZnO

Energies ◽  
2021 ◽  
Vol 14 (23) ◽  
pp. 8019
Author(s):  
Arda Hatunoglu ◽  
Alessandro Dell’Era ◽  
Luca Del Zotto ◽  
Andrea Di Carlo ◽  
Erwin Ciro ◽  
...  
Keyword(s):  
High Temperature ◽  
Sorption Capacity ◽  
Rate Constant ◽  
Low Cost ◽  
Fixed Bed ◽  
Breakthrough Curves ◽  
Fixed Bed Reactor ◽  
Deactivation Model ◽  
Security Issues ◽  
Before And After

High-temperature desulfurization techniques are fundamental for the development of reliable and efficient conversion systems of low-cost fuels and biomass that answer to the nowadays environmental and energy security issues. This is particularly true for biomass gasification coupled to SOFC systems where the sulfur content has to be minimized before being fed to the SOFC. Thus, commercially available zinc oxide has been studied and characterized as a desulfurizing agent in a fixed-bed reactor at high temperatures from 400 °C to 600 °C. The sorbent material was characterized by XRD, BET, SEM, and EDS analyses before and after adsorption. The sorbent’s sorption capacity has been evaluated at different temperatures, as well as the breakthrough curves. Moreover, the kinetic parameters as the initial sorption rate constant k0, the deactivation rate constant kd, and the activation energy have been calculated using the linearized deactivation model. The best performances have been obtained at 550 °C, obtaining a sorption capacity of 5.4 g per 100 g of sorbent and a breakthrough time of 2.7 h. These results can be used to extend ZnO desulfurization techniques to a higher temperature than the ones used today (i.e., 550 °C with respect to 400 °C).

scholarly journals Comparison of Nature and Synthetic Zeolite for Waste Battery Electrolyte Treatment in Fixed-Bed Adsorption Column

Energies ◽  
2022 ◽  
Vol 15 (1) ◽  
pp. 347
Author(s):  
Cong Yang ◽  
Yifei Wang ◽  
Abdullatif Alfutimie
Keyword(s):  
Fixed Bed ◽  
Co2 Reduction ◽  
Breakthrough Curves ◽  
Renewable Energies ◽  
Fixed Bed Reactor ◽  
Zeolite A ◽  
Energy Needs ◽  
Fixed Bed Adsorption ◽  
Before And After ◽  
Battery Electrolyte

To support a sustainable energy development, CO2 reduction for carbon neutralization and water-splitting for hydrogen economy are two feasible technical routes, both of which require a significant input of renewable energies. To efficiently store renewable energies, secondary batteries will be applied in great quantity, so that a considerable amount of energy needs to be invested to eliminate the waste battery electrolyte pollution caused by heavy metals including Cu2+, Zn2+ and Pb2+. To reduce this energy consumption, the removal behaviors of these ions by using clinoptilolite and zeolite A under 5, 7 and 10 BV h−1 in a fixed-bed reactor were investigated. The used zeolites were then regenerated by a novel NH4Cl solution soaking, coupled with the ultrasonication method. Further characterizations were carried out using scanning electron microscopy, N2 adsorption and desorption test, and wide-angle X-ray diffraction. The adsorption breakthrough curves revealed that the leaching preference of clinoptilolite was Pb2+ > Cu2+ > Zn2+, while the removal sequence for zeolite A was Zn2+ > Cu2+ > Pb2+. The maximum removal percentage of Zn2+ ions for clinoptilolite under 5 BV h−1 was 21.55%, while it was 83.45% for zeolite A. The leaching ability difference was also discussed combining with the characterization results. The fact that unit cell stayed the same before and after the regeneration treatment approved the efficacy of the regeneration method, which detached most of the ions while doing little change to both morphology and crystallinity of the zeolites. By evaluating the pH and conductivity changes, the leaching mechanisms by adsorption and ion exchange were further studied.

A Novel Fe 1-xO-Based Fused Iron Catalyst for Fischer-Tropsch Synthesis with the High Olefine Selectivity

2012 ◽  
Vol 512-515 ◽  
pp. 2207-2211
Author(s):  
Hua Zhang Liu ◽  
Xia Zhen Yang ◽  
Ya Qing Cen ◽  
Hao Dong Tang
Keyword(s):  
High Temperature ◽  
Low Temperature ◽  
High Stability ◽  
Iron Catalyst ◽  
Low Cost ◽  
Fixed Bed ◽  
Fixed Bed Reactor ◽  
Preparation Process ◽  
Fischer Tropsch ◽  
Fused Iron Catalyst

The performance and stability for FTS was studied on novel Fe1-xO-based iron catalyst (FIC) in agitated slurry reactor (ASR) and fixed bed reactor (FBR), and compared with precipitation-iron catalyst (PIC). The studied results indicate that novel Fe1-xO-based iron catalyst has the high conversion and high stability, especially, the high alkene selectivity in C2 ~ C4 products that the ratios of olefines and paraffines the more than 9 and the low cost, the preparation process and the high mechanical intensity. The catalyst can be used at FBR or ASR, and FTS at high temperature or low temperature.

scholarly journals Organic matter removal via activated sludge immobilized gravel in fixed bed reactor

2020 ◽  
Vol 191 ◽  
pp. 03006
Author(s):  
Banu Sizirici ◽  
Ibrahim Yildiz
Keyword(s):  
Organic Matter ◽  
Activated Sludge ◽  
Removal Rate ◽  
Low Cost ◽  
Fixed Bed ◽  
Breakthrough Curves ◽  
Fixed Bed Reactor ◽  
Synthetic Wastewater ◽  
Wastewater Sample ◽  
Bed Height

In this study, the adsorption capability of the activated sludge immobilized gravel as a low-cost and efficient adsorbent to remove organic matter in terms of chemical oxygen demand (COD) from synthetic wastewater was investigated using fixed bed columns. The effects of parameters including column pack height and influent COD concentrations on removal efficiencies were assessed through breakthrough curves. It was found that the removal efficiency increased when fixed bed height was increased and influent COD concentration was decreased. The maximum COD removal rate of 36.35%, was obtained for a medium-strength wastewater sample with 1166 mg/L of COD concentration when the bed height was 2 cm, and the flow rate was 11 mL/min. Activated sludge immobilized gravel can be utilized as a low cost bio-filter to remove organic material from wastewater.

The Performance of Regeneration for Modified Semi-Coke Supported (Fe, Zn, ce) Sorbents

2012 ◽  
Vol 524-527 ◽  
pp. 1140-1144
Author(s):  
Jie Mi ◽  
Meng Yu ◽  
Su Li Shang
Keyword(s):  
Oxygen Content ◽  
Oxygen Concentration ◽  
Fixed Bed ◽  
Space Velocity ◽  
Breakthrough Curves ◽  
Fixed Bed Reactor ◽  
Hot Gas ◽  
Before And After ◽  
Sulfur Capacity ◽  
Hot Gas Desulfurization

In this study, the regeneration behavior of modified semi-coke supported (Fe, Zn, Ce) sorbents were investigated using a fixed bed reactor. The effects of the regeneration temperature, space velocity and oxygen concentration have been considered in order to obtain suitable regeneration conditions. The most suitable regeneration conditions were obtained including 650°C regeneration temperature, 4vol.% of oxygen content and 4000h-1 of space velocity. Typical properties of the sorbents before and after regeneration were characterized using XRD and BET methods. Then the sorbents were tested 3 cycle experiments of desulfurization and regeneration for the purpose of duration test. The breakthrough curves changed slightly and the sulfur capacity only decreased 14.2%, it proved that the sorbents had good regenerability, which implied that the sorbents could be used for hot gas desulfurization.

scholarly journals Hierarchical H-ZSM5 zeolites based on natural kaolinite as a high-performance catalyst for methanol to aromatic hydrocarbons conversion

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Ahmad Asghari ◽  
Mohammadreza Khanmohammadi Khorrami ◽  
Sayed Habib Kazemi
Keyword(s):  
Pore Size ◽  
Aromatic Hydrocarbons ◽  
High Performance ◽  
Low Cost ◽  
Direct Synthesis ◽  
Fixed Bed ◽  
Methanol Conversion ◽  
Catalytic Performance ◽  
Fixed Bed Reactor ◽  
Good Prospect

AbstractThe present work introduces a good prospect for the development of hierarchical catalysts with excellent catalytic performance in the methanol to aromatic hydrocarbons conversion (MTA) process. Hierarchical H-ZSM5 zeolites, with a tailored pore size and different Si/Al ratios, were synthesized directly using natural kaolin clay as a low-cost silica and aluminium resource. Further explored for the direct synthesis of hierarchical HZSM-5 structures was the steam assisted conversion (SAC) with a cost-effective and green affordable saccharide source of high fructose corn syrup (HFCS), as a secondary mesopore agent. The fabricated zeolites exhibiting good crystallinity, 2D and 3D nanostructures, high specific surface area, tailored pore size, and tunable acidity. Finally, the catalyst performance in the conversion of methanol to aromatic hydrocarbons was tested in a fixed bed reactor. The synthesized H-ZSM5 catalysts exhibited superior methanol conversion (over 100 h up to 90%) and selectivity (over 85%) in the methanol conversion to aromatic hydrocarbon products.

scholarly journals Continuous Adsorption Modeling and Fixed Bed Column Studies: Adsorption of Tannery Wastewater Pollutants Using Beach Sand

2020 ◽  
Vol 2020 ◽  
pp. 1-9 ◽  
Author(s):  
Ghita El Mouhri ◽  
Mohammed Merzouki ◽  
Hajar Belhassan ◽  
Youssef Miyah ◽  
Halima Amakdouf ◽  
...  
Keyword(s):  
Low Cost ◽  
Fixed Bed ◽  
Beach Sand ◽  
Natural Material ◽  
Tannery Effluent ◽  
Column Studies ◽  
Continuous Adsorption ◽  
Column Adsorption ◽  
Before And After ◽  
Wastewater Pollutants

This study deals with the removal of residual pollutants from tanning wastewater by continuous adsorption mechanism, using local sand as a low-cost adsorbent. The possibility of pretreating a complex tannery effluent heavily loaded with a natural material such as sand is significant. The characterization of the adsorbent before and after continuous adsorption was performed by X-ray diffraction, Fourier transform infrared spectroscopy, and scanning electron microscopy. Column studies were also carried out to evaluate the performance of the adsorbent and the efficiency of column adsorption. The adsorption kinetic rate seems to be strongly influenced by certain parameters such as the particle size of the material used, the withdrawal rate of the influent and the height of the adsorbent bed, and optimized parameters were found to be 63 μm, 15 ml·min−1, and 7 cm, respectively, and the color removal has achieved maximum values which vary between 95 and 100%. The results suggest that sand can be used as an economical adsorbent for the removal of color from the wastewater of the tanning industries.

scholarly journals Production of CO2 in crude oil bioremediation in clay soil

2005 ◽  
Vol 48 (spe) ◽  
pp. 249-255 ◽  
Author(s):  
Sandro José Baptista ◽  
Magali Christe Cammarota ◽  
Denize Dias de Carvalho Freire
Keyword(s):  
Crude Oil ◽  
Petroleum Hydrocarbons ◽  
Clay Soil ◽  
Fixed Bed ◽  
Bacterial Count ◽  
Fixed Bed Reactor ◽  
Total Petroleum Hydrocarbons ◽  
Co2 Production ◽  
Oil And Grease ◽  
Before And After

The aim of the present work was to evaluate the biodegradation of petroleum hydrocarbons in clay soil a 45-days experiment. The experiment was conducted using an aerobic fixed bed reactor, containing 300g of contaminated soil at room temperature with an air rate of 6 L/h. The growth medium was supplemented with 2.5% (w/w) (NH4)2SO4 and 0.035% (w/w) KH2PO4. Biodegradation of the crude oil in the contaminated clay soil was monitored by measuring CO2 production and removal of organic matter (OM), oil and grease (OandG), and total petroleum hydrocarbons (TPH), measured before and after the 45-days experiment, together with total heterotrophic and hydrocarbon-degrading bacterial count. The best removals of OM (50%), OandG (37%) and TPH (45%) were obtained in the bioreactors in which the highest CO2 production was achieved.

Innovative low cost procedure for nutrient removal as an integrated element of a decentralised water management concept for rural areas

2001 ◽  
Vol 44 (1) ◽  
pp. 105-112 ◽  
Author(s):  
M. Burde ◽  
F. Rolf ◽  
F. Grabowski
Keyword(s):  
Wastewater Treatment ◽  
Nutrient Removal ◽  
Rural Areas ◽  
Municipal Wastewater ◽  
Wastewater Treatment Plants ◽  
Low Cost ◽  
Fixed Bed ◽  
Extreme Rainfall ◽  
Fixed Bed Reactor ◽  
Soil Zone

The absence of large rivers with rather high niveau of self purifying effect in parts of east Germany leads to a discharging of the effluent of wastewater treatment plants into the groundwater in many cases. One useful consequence is the idea of realisation of decentralised measures and concepts in urban water resources management concerning municipal wastewater as well as rainfall, precipitation. At the same time, only the upper soil zone - a few decimetres - is water - saturated and thus discharge effective, even when extreme rainfall takes place. Underneath, however, there generally exists an unsaturated soil zone, which is up to now a rather unexplored retardation element of the hydrologic- and substrate-cycle. Nutrient removal in small wastewater treatment plants that are emptying into ground waters is often beneficial. The presented studies optimised an inexpensive method of subsequent enhanced wastewater treatment. The developed reactor is similar to a concentrated subsoil passage. The fixed bed reactor is divided in two sections to achieve aerobic and anoxic conditions for nitrification/denitrification processes. To enhance phosphorus removal, ferrous particles are put into the aerobic zone. Two series of column tests were carried out and a technical pilot plant was built to verify the efficiency of the process. The results show that this method can be implemented successfully.

Removal of VOCs Using Sludge-Based Adsorbents

2012 ◽  
Vol 599 ◽  
pp. 305-308 ◽  
Author(s):  
Ping Fang ◽  
Chao Ping Cen ◽  
Hong Tao Zhang ◽  
Zi Jun Tang ◽  
Ding Sheng Chen ◽  
...  
Keyword(s):  
Adsorption Capacity ◽  
Physical Adsorption ◽  
Low Cost ◽  
Fixed Bed ◽  
Cost Effective ◽  
Langmuir Adsorption Isotherm ◽  
Fixed Bed Reactor ◽  
Dynamic Adsorption ◽  
Langmuir Adsorption ◽  
Isotherm Equations

Efficient and cost-effective sludge-based adsorbents were developed and the adsorption of VOCs on the sludge-based adsorbents was studied in a fixed bed reactor. The results indicate that the adsorption of VOCs on sludge-based adsorbents is typical physical adsorption, the dynamic adsorption capacity of VOCs on adsorbents sharply increases as the VOCs concentration is increased at first, then increasing gradually, at last retains stable with the change of VOCs concentration. The dynamic adsorption capacity of sludge-based adsorbents for VOCs is O-Xylene > Butylcetate > Toluene > Ethylacetate > Benzene > Propanone > n-Hexane, the maximum dynamic adsorption capacity is 0.247, 0.225, 0.192, 0.186, 0.180, 0.176, 0.133g/g, respectively. Meanwhile the adsorption of VOCs on sludge-based adsorbents corresponds to the Langmuir adsorption isotherm equations. The sludge-based adsorbent is a low-cost alternative to activated carbon for VOCs treatment, and this technology is a promising method for the VOCs removal.

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