scholarly journals Arsenic Removal from Aqueous Solution Using Pure and Metal-Doped Titania Nanoparticles Coated on Glass Beads: Adsorption and Column Studies

2013 ◽  
Vol 2013 ◽  
pp. 1-17 ◽  
Author(s):  
M. Ihsan Danish ◽  
Ishtiaq A. Qazi ◽  
Akif Zeb ◽  
Amir Habib ◽  
M. Ali Awan ◽  
...  
Keyword(s):  
Arsenic Removal ◽  
Fixed Bed ◽  
Visible Region ◽  
Glass Beads ◽  
Operating Conditions ◽  
Titania Nanoparticles ◽  
World Population ◽  
Impregnation Method ◽  
Doped Titania ◽  
Metal Doped

Nanosized metal oxide, Titania, provides high surface area and specific affinity for the adsorption of heavy metals, including arsenic (As), which is posing a great threat to the world population due to its carcinogenic nature. In this study, As(III) adsorption was studied on pure and metal- (Ag- and Fe-) doped Titania nanoparticles. The nanoparticles were synthesized by liquid impregnation method with some modifications, with crystallite size in the range of 30 to 40 nm. Band gap analysis, using Kubelka-Munk function showed a shift of absorption band from UV to visible region for the metal-doped Titania. Effect of operational parameters like dose of nanoparticles, initial As(III) concentration, and pH was evaluated at 25°C. The data obtained gave a good fit with Langmuir and Freundlich isotherms and the adsorption was found to conform to pseudo-second-order kinetics. In batch studies, over 90% of arsenic removal was observed for both types of metal-doped Titania nanoparticles from a solution containing up to 2 ppm of the heavy metal. Fixed bed columns of nanoparticles, coated on glass beads, were used for As(III) removal under different operating conditions. Thomas and Yoon-Nelson models were applied to predict the breakthrough curves and to find the characteristic column parameters useful for process design. The columns were regenerated using 10% NaOH solution.

Activity of Copper and Nickel Loaded on HZSM-5Zeolite Based Catalyst for Steam Reforming of Glycerol to Hydrogen

2014 ◽  
Vol 699 ◽  
pp. 504-509
Author(s):  
Hafizah Abdul Halim Yun ◽  
Ramli Mat ◽  
Tuan Amran Tuan Abdullah ◽  
Mahadhir Mohamed ◽  
Anwar Johariand Asmadi Ali
Keyword(s):  
Hydrogen Production ◽  
Steam Reforming ◽  
Fixed Bed ◽  
Operating Conditions ◽  
Zeolite Catalysts ◽  
Fixed Bed Reactor ◽  
Molar Ratio ◽  
Hydrogen Yield ◽  
Impregnation Method ◽  
Glycerol Conversion

The study focuses on hydrogen production via glycerol steam reforming over copper and nickel loaded on HZSM-5 zeolite based catalyst. The catalysts were prepared by using different loading amount of copper (0-10wt%) and nickel (0-10wt%) on HZSM-5 zeolite catalysts through wet impregnation method and was characterized by X-Ray Diffraction (XRD). The performances of catalysts were evaluated in terms of glycerol conversion and hydrogen production at 500°C using 6:1 of water to glycerol molar ratio (WGMR) in a tubular fixed bed reactor. All the catalysts had achieved more than 85% of glycerol conversion except that of 5%Cu loaded on HZSM-5 catalyst. The addition of nickel into 5% Cu/HZSM-5 catalyst had increased the hydrogen yield. Similar trend was observed when copper was added into Ni/HZSM-5 catalyst but using copper loaded on HZSM-5 alone was unable to produce hydrogen compared to using nickel catalyst alone. It showed that copper acted as a promoter for hydrogen production. It was established that a 5wt% of Cu with 10wt% of Ni loaded on HZSM-5 catalyst showed significant improvement in terms of hydrogen yield and gaseous product compositions at selected operating conditions.

scholarly journals Metal doped Titania nanoparticles as efficient photocatalyst for dyes degradation

2020 ◽  
pp. 101312
Author(s):  
Maria Sadia ◽  
RobinaNaz ◽  
Jehangir Khan ◽  
Muhammad Zahoor ◽  
Riaz Ullah ◽  
...  
Keyword(s):  
Titania Nanoparticles ◽  
Doped Titania ◽  
Metal Doped ◽  
Dyes Degradation

Visible-Light Photodegradation of Diisopropanolamine Using Bimetallic Cu-Fe/TiO2 Photocatalyst

2013 ◽  
Vol 845 ◽  
pp. 421-425 ◽  
Author(s):  
Raihan Mahirah Ramli ◽  
Chong Fai Kait ◽  
Abdul Aziz Omar
Keyword(s):  
Visible Region ◽  
Titania Nanoparticles ◽  
Point Of Zero Charge ◽  
Diffraction Field ◽  
Impregnation Method ◽  
X Ray Diffraction ◽  
Wet Impregnation ◽  
X Ray ◽  
Vis Spectroscopy ◽  
Wet Impregnation Method

Titania nanoparticles, TiO2 were synthesized via microemulsion method prior to monometallic (Fe, Cu) or bimetallic (CuFe) incorporation using wet impregnation method. The prepared photocatalysts were characterized using X-ray diffraction, field emission scanning electron microscopy, diffuse reflectance UV-Vis spectroscopy and point of zero charge. The addition of metals, especially Cu enhanced the absorbance in the visible region. The lowest band gap was observed for the bimetallic Cu-Fe/TiO2 (2.77 eV) compared to bare TiO2 (3.05 eV). The performance of the photocatalysts for photodegradation of diisopropanolamine (DIPA) at pH 8 was determined using a batch glass reactor under simulated sunlight (980 W/m2). The best performance was displayed by Cu-Fe/TiO2 with the highest DIPA removal of 92%.

scholarly journals Comparison of Adsorption Capability of Activated Carbon and Metal Doped TiO2for Geosmin and 2-MIB Removal from Water

2015 ◽  
Vol 2015 ◽  
pp. 1-11 ◽  
Author(s):  
Aisha Asghar ◽  
Zahiruddin Khan ◽  
Nida Maqbool ◽  
Ishtiaq A. Qazi ◽  
Muhammad Ali Awan
Keyword(s):  
Activated Carbon ◽  
Room Temperature ◽  
Freundlich Isotherm ◽  
Titania Nanoparticles ◽  
Contaminant Removal ◽  
Consumer Complaints ◽  
Freundlich Isotherms ◽  
Doped Titania ◽  
Metal Doped ◽  
Stock Solutions

This study stemmed from consumer complaints about earthy and musty off-flavours in treated water of Rawal Lake Filtration Plant. In recent years, several novel adsorbents have been developed from nanomaterials for enhancing the contaminant removal efficiency. This paper presents preparation and the use of new adsorbents Pt doped titania and Fe doped titania, for the adsorption capacity of Geosmin and 2-MIB from water under laboratory conditions and their comparison, with most widely used activated carbon, under batch and column experiments. Stock solutions were prepared by using Geosmin and 2-MIB standards, procured by Sigma Aldrich (England). Samples were analysed using SPME-GC-FID. The adsorption of Geosmin and 2-MIB on GAC conformed to the Freundlich isotherm, while that of adsorption on metal doped titania fit equally well to both Langmuir and Freundlich isotherms. Moreover, data, generated for the kinetic isotherm, confirmed that Geosmin and 2-MIB removal is a function of contact time. Breakthrough column tests using 125 mg/L Pt doped titania nanoparticles, coated on glass beads against 700 ng/L of off-flavours, attained later breakthrough and exhaustion points and removed 98% of Geosmin and 97% of 2-MIB at room temperature. All columns could be regenerated using 50 mL 0.1 molar sodium hydroxide.

As(III) Removal by Dynamic Adsorption onto Amberlite XAD7 Functionalized with Crown Ether and Doped with Fe(III) Ions

2019 ◽  
Vol 70 (7) ◽  
pp. 2330-2334
Author(s):  
Mihaela Ciopec ◽  
Adina Negrea ◽  
Narcis Duteanu ◽  
Corneliu Mircea Davidescu ◽  
Iosif Hulka ◽  
...  
Keyword(s):  
Adsorption Process ◽  
Arsenic Removal ◽  
Arsenic Concentration ◽  
Fixed Bed ◽  
World Health ◽  
Arsenic Content ◽  
Arsenic Adsorption ◽  
Stage Of Development ◽  
Wide Range ◽  
Health Organization

Arsenic content in groundwater�s present a wide range of concentration, ranging from hundreds of micrograms to thousands of micrograms of arsenic per litter, while the maximum permitted arsenic concentration established by World Health Organization (WHO) is 10 mg L-1. According to the WHO all people, regardless of their stage of development and their social economic condition, have the right to have access to adequate drinking water. The most efficient and economic technique used for arsenic removal is represented by adsorption. In order to make this remediation technique more affordable and environmentally friendly is important to new materials with advance adsorbent properties. Novelty of present paper is represented by the usage of a new adsorbent material obtained by physical - chemical modification of Amberlite XAD polymers using crown ethers followed by iron doping, due to well-known affinity of arsenic for iron ions. Present paper aims to test the obtained modified Amberlite polymer for arsenic removal from real groundwater by using adsorption in a fixed bed column, establishing in this way a mechanism for the adsorption process. During experimental work was studied the influence of competing ions from real water into the arsenic adsorption process.

Tertiary Nitrification Pilot Plants on Parisian Waste Water

1990 ◽  
Vol 22 (1-2) ◽  
pp. 347-352 ◽  
Author(s):  
C. Paffoni ◽  
B. Védry ◽  
M. Gousailles
Keyword(s):  
Waste Water ◽  
Metropolitan Area ◽  
Fixed Bed ◽  
Point Of View ◽  
Operating Conditions ◽  
Research Center ◽  
Daily Output ◽  
Practical Point ◽  
Fixed Bed Reactors

The Paris Metropolitan area, which contains over eight million inhabitants, has a daily output of about 3 M cu.meters of wastewater, the purification of which is achieved by SIAAP (Paris Metropolitan Area Sewage Service) in both Achères and Valenton plants. The carbon pollution is eliminated from over 2 M cu.m/day at Achères. In order to improve the quality of output water, its tertiary nitrification in fixed-bed reactors has been contemplated. The BIOFOR (Degremont) and BIOCARBONE (OTV) processes could be tested in semi-industrial pilot reactors at the CRITER research center of SIAAP. At a reference temperature of 13°C, the removed load is approximately 0.5 kg N NH4/m3.day. From a practical point of view, it may be asserted that in such operating conditions as should be at the Achères plant, one cubic meter of filter can handle the tertiary nitification of one cubic meter of purified water per hour at an effluent temperature of 13°C.

Analysis of NiMoP/γ-Al2O3 Catalyst Preparation with Impregnation and Microwave Polyol Methods for Bio-Jet Production

2020 ◽  
Vol 1000 ◽  
pp. 257-264
Author(s):  
Bambang Heru Susanto ◽  
Joshua Raymond Valentino Siallagan
Keyword(s):  
Coconut Oil ◽  
Catalyst Preparation ◽  
Operating Conditions ◽  
Catalyst Loading ◽  
Impregnation Method ◽  
Conversion Yield ◽  
Jet Production ◽  
Cracking Process ◽  
Catalyst Impregnation ◽  
Rate Conversion

Bio-Jet could be produced by the synthesis of vegetable oil through the hydrodeoxygenation, decarboxylation, decarbonization, and catalytic cracking process. Physical characteristics, activities, and selectivity of the catalyst used will determine the rate, conversion, and yield of the reaction that being carried out. This study aims to compare and obtain the best characteristics of NiMoP/γ-Al2O3 catalysts synthesized using two types of preparation, impregnation and microwave polyol methods, which will be used for bio-jet production. The impregnation method takes more than 24 hours for catalyst preparation, while microwave polyols that use microwaves can synthesize catalysts faster. Both catalysts have almost the same loading on the weight of the catalyst, which in the microwave polyol method has a more dispersed promotor and active site, although the crystallinity level is deficient and tends to be amorphous compared to the impregnation method with high crystallinity. In bio-jet synthesis reaction with operating conditions of 5% catalyst loading by comparison to Coconut Oil, 400°C, and 15 bar, the conversion, yield, and selectivity of catalyst impregnation were 91.705%, 47.639%, and 84.511%, while microwave polyol catalysts were 90.296%, 42.752%, and 82.517%, respectively. In conclusion, microwave polyol provides a more effective and efficient preparation method.

CO2 valorization into synthetic natural gas (SNG) using a Co–Ni bimetallic Y2O3 based catalysts

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Radwa A. El-Salamony ◽  
Sara A. El-Sharaky ◽  
Seham A. Al-Temtamy ◽  
Ahmed M. Al-Sabagh ◽  
Hamada M. Killa
Keyword(s):  
Reaction Mechanism ◽  
Natural Gas ◽  
Fixed Bed ◽  
Catalytic Performance ◽  
Fixed Bed Reactor ◽  
Molar Ratio ◽  
Impregnation Method ◽  
Synthetic Natural Gas ◽  
Methanation Reaction ◽  
Co2 Valorization

Abstract Recently, because of the increasing demand for natural gas and the reduction of greenhouse gases, interests have focused on producing synthetic natural gas (SNG), which is suggested as an important future energy carrier. Hydrogenation of CO2, the so-called methanation reaction, is a suitable technique for the fixation of CO2. Nickel supported on yttrium oxide and promoted with cobalt were prepared by the wet-impregnation method respectively and characterized using SBET, XRD, FTIR, XPS, TPR, and HRTEM/EDX. CO2 hydrogenation over the Ni/Y2O3 catalyst was examined and compared with Co–Ni/Y2O3 catalysts, Co% = 10 and 15 wt/wt. The catalytic test was conducted with the use of a fixed-bed reactor under atmospheric pressure. The catalytic performance temperature was 350 °C with a supply of H2:CO2 molar ratio of 4 and a total flow rate of 200 mL/min. The CH4 yield was reached 67%, and CO2 conversion extended 48.5% with CO traces over 10Co–Ni/Y2O3 catalyst. This encourages the direct methanation reaction mechanism. However, the reaction mechanism over Ni/Y2O3 catalyst shows different behaviors rather than that over bi-metal catalysts, whereas the steam reforming of methane reaction was arisen associated with methane consumption besides increase in H2 and CO formation; at the same temperature reaction.

scholarly journals Performance Analysis of TiO2-Modified Co/MgAl2O4 Catalyst for Dry Reforming of Methane in a Fixed Bed Reactor for Syngas (H2, CO) Production

Energies ◽  
2021 ◽  
Vol 14 (11) ◽  
pp. 3347
Author(s):  
Arslan Mazhar ◽  
Asif Hussain Khoja ◽  
Abul Kalam Azad ◽  
Faisal Mushtaq ◽  
Salman Raza Naqvi ◽  
...  
Keyword(s):  
Catalytic Activity ◽  
Fixed Bed ◽  
Catalytic Performance ◽  
Dry Reforming ◽  
Fixed Bed Reactor ◽  
Dry Reforming Of Methane ◽  
Catalyst Stability ◽  
Feed Ratio ◽  
Catalyst Loading ◽  
Impregnation Method

Co/TiO2–MgAl2O4 was investigated in a fixed bed reactor for the dry reforming of methane (DRM) process. Co/TiO2–MgAl2O4 was prepared by modified co-precipitation, followed by the hydrothermal method. The active metal Co was loaded via the wetness impregnation method. The prepared catalyst was characterized by XRD, SEM, TGA, and FTIR. The performance of Co/TiO2–MgAl2O4 for the DRM process was investigated in a reactor with a temperature of 750 °C, a feed ratio (CO2/CH4) of 1, a catalyst loading of 0.5 g, and a feed flow rate of 20 mL min−1. The effect of support interaction with metal and the composite were studied for catalytic activity, the composite showing significantly improved results. Moreover, among the tested Co loadings, 5 wt% Co over the TiO2–MgAl2O4 composite shows the best catalytic performance. The 5%Co/TiO2–MgAl2O4 improved the CH4 and CO2 conversion by up to 70% and 80%, respectively, while the selectivity of H2 and CO improved to 43% and 46.5%, respectively. The achieved H2/CO ratio of 0.9 was due to the excess amount of CO produced because of the higher conversion rate of CO2 and the surface carbon reaction with oxygen species. Furthermore, in a time on stream (TOS) test, the catalyst exhibited 75 h of stability with significant catalytic activity. Catalyst potential lies in catalyst stability and performance results, thus encouraging the further investigation and use of the catalyst for the long-run DRM process.

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