Removal of Uranium From Aqueous Solution by Chitosan and Ferrous Ions

2010 ◽  
Author(s):  
Jing-song Wang ◽  
Zheng-lei Bao ◽  
Si-guang Chen ◽  
Jin-hui Yang
Keyword(s):  
Aqueous Solution ◽  
Removal Rate ◽  
Synergetic Effect ◽  
Ferrous Ions ◽  
Experimental Conditions ◽  
Initial Concentration ◽  
Batch Systems ◽  
Uranium Ions ◽  
High Removal Rate ◽  
The Given

This study focuses on developing a new method to remove uranium from aqueous solution. Chitosan and ferrous ions were used together to remove uranium ions from aqueous solution. Through two-step pH adjustment, the uptake behavior of chitosan and ferrous ions toward uranium in aqueous solution using batch systems were studied in different experimental conditions. The experimental results indicated that the removal of uranium by synergetic effect of chitosan and ferrous ions was more effective than the way of adsorbing uranium ions by chitosan alone. Under the given experimental conditions, the concentration of the residual uranium in the effluent after chitosan and ferrous ions treatment could meet the discharge standard (< 0.05mg·l−1) when initial concentration of uranium ions was 10 mg·l−1 or 100 mg·l−1. The synergetic effect of chitosan and ferrous ions including adsorption, coacervation and coprecipitation, are responsible for the high removal rate of uranium.

Removal of Uranium From Aqueous Solution by Chitosan and Ferrous Ions

2011 ◽  
Vol 133 (8) ◽  
Author(s):  
Jing-song Wang ◽  
Zheng-lei Bao ◽  
Si-guang Chen ◽  
Jin-hui Yang
Keyword(s):  
Aqueous Solution ◽  
Removal Rate ◽  
Synergetic Effect ◽  
Ferrous Ions ◽  
Experimental Conditions ◽  
Batch Systems ◽  
Uranium Ions ◽  
High Removal Rate ◽  
Ion Treatment ◽  
The Given

This study focuses on developing a new method to remove uranium from aqueous solution. Chitosan and ferrous ions were used together to remove uranium ions from aqueous solution. Through two-step pH adjustment, the uptake behavior of chitosan and ferrous ions toward uranium in aqueous solution using batch systems was studied in different experimental conditions. The experimental results indicated that the removal of uranium by the synergetic effect of chitosan and ferrous ions was more effective than the way of adsorbing uranium ions by chitosan alone. Under the given experimental conditions, the concentration of the residual uranium in the effluent after the chitosan and ferrous ion treatment could meet the discharge standard (<0.05 mg l−1) when the initial concentration of uranium ions was 10 mg l−1 or 100 mg l−1. The synergetic effect of chitosan and ferrous ions, including adsorption, coacervation, and coprecipitation, was responsible for the high removal rate of uranium.

scholarly journals Evaluation of La-Doped Mesoporous Bioactive Glass as Adsorbent and Photocatalyst for Removal of Methylene Blue from Aqueous Solution

2015 ◽  
Vol 2015 ◽  
pp. 1-11
Author(s):  
Liying Li ◽  
Huanrui Shi ◽  
Lu Chen ◽  
Qianxuan Yuan ◽  
Xi Chen ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Methylene Blue ◽  
Bioactive Glass ◽  
Removal Rate ◽  
Mesoporous Structure ◽  
Photocatalytic Effect ◽  
New Material ◽  
High Removal Rate ◽  
La Doped ◽  
Mesoporous Bioactive Glass

A series of La-doped mesoporous bioactive glass (BG-La) materials with excellent biosafety and hypotoxicity have been prepared and tested as adsorbent. The study was aimed to evaluate the possibility of utilizing BG-La for the adsorptive removal of methylene blue (MB) from aqueous solution and test the adsorption and desorption behavior of this new material. The process parameters affecting adsorption behaviors such as pH, contact time, and initial concentration and the photocatalytic degradation of MB were systematically investigated. The result showed that BG-La had excellent removal rate (R) of MB, and BG-La showed better photocatalytic effect than undoped mesoporous bioactive glass (BG). Furthermore, the MB loaded BG-La was easily desorbed with acid solution due to its electronegativity and mesoporous structure. The result indicated that these materials can be employed as candidates for removal of dye pollutant owing to their high removal rate, excellent photocatalytic effect, desorption performance, and their reusability.

Removal of cadmium and zinc from contaminated wastewater using Rhodobacter sphaeroides

2016 ◽  
Vol 75 (11) ◽  
pp. 2489-2498 ◽  
Author(s):  
Xiaomin Li ◽  
Weihua Peng ◽  
Yingying Jia ◽  
Lin Lu ◽  
Wenhong Fan
Keyword(s):  
Rhodobacter Sphaeroides ◽  
Removal Rate ◽  
Inoculum Size ◽  
Pilot Test ◽  
Optimal Conditions ◽  
Practical Application ◽  
Experimental Conditions ◽  
Initial Concentration ◽  
Effects Of Ph ◽  
Remediation Time

Rhodobacter sphaeroides was used for bioremediation of wastewater polluted with cadmium (Cd) and zinc (Zn). The tolerance of the microorganism to selected heavy metals (HMs), as well as the effects of pH, temperature and inoculum size on the removal rate, was investigated. The remediation effects of R. sphaeroides were analysed at different initial concentrations of HMs. Bioremediation mechanisms were thoroughly discussed based on the results from the cell characterisation analysis. Cd and Zn could inhibit the growth of R. sphaeroides. However, Cd was more toxic than Zn, with corresponding EC50 values of 5.34 and 69.79 mg L−1. Temperature and pH had greater influence on the removal rate of HMs than inoculum size. The optimal conditions for temperature and pH were 35 °C–40 °C and pH 7, respectively. Initial concentration of HMs and remediation time also affected the removal rate. Rhodobacter sphaeroides had a relatively higher remediation effect under the present experimental conditions. The removal rates for Cd and Zn reached 97.92% and 97.76%, respectively. Results showed that biosorption and HM precipitation were the main bioremediation mechanisms. This information is necessary to better understand the removal mechanism of R. sphaeroides, and is significant for its pilot test and future practical application.

Studies on the Treatment of Wastewaters Containing Cr6+ with Iron Oxide-Silica Composite Materials Prepared by Different Methods

2014 ◽  
Vol 353 ◽  
pp. 33-38
Author(s):  
Rafique Ullah ◽  
Biplob Kumer Deb ◽  
Mohammad Yousuf Ali Mollah
Keyword(s):  
Aqueous Solution ◽  
Iron Oxide ◽  
Adsorption Isotherm ◽  
Aqueous Solutions ◽  
Order Kinetic ◽  
Efficient Technology ◽  
Experimental Conditions ◽  
Initial Concentration ◽  
Oxide Composite ◽  
Chromium Vi

Chromium (VI) is known to be carcinogenic to humans and thus it is important to ensure the removal of Chromium (VI) from aqueous solutions and industrial effluents. The present study introduces a good alternative method for Cr (VI) removal from aqueous solutions at ambient temperature by adsorption, allowing the development of newer, lower operational cost, and more efficient technology than other processes already in use. Adsorption was found to be dependent on pH and initial concentration of Cr (VI) solution. Results of adsorption studies suggest that pristine iron oxide and silicon (IV) oxide removes 72.10% and 24.73%, respectively. The iron oxide – silicon (IV) oxide composite, prepared in this work, removes 93.88% Cr (VI) in 20 minutes from aqueous solution at an initial concentration of 50 mgL-1at pH 4.8 ± 0.2. The effect of concentration, contact time, adsorbent dose and solution pH on the adsorption of Cr (VI) were studied in detail in batch experiments. Studies of the sorption kinetics shows that equilibrium adsorption was attained in 20 minutes depending on other experimental conditions. The kinetic data justified Lagergren’s first-order kinetic equation. Adsorption isotherm study showed that the results fulfilled the Langmuir Model of adsorption isotherm. The maximum adsorption (98.28%) was recorded at pH 3 in 90 minutes for the initial Cr (VI) concentration of 50 mg L-1. Therefore, it can be concluded that iron oxide – silicon (IV) oxide composite is a potential adsorbent for adsorption of Cr (VI) from aqueous solution.

Study on Cu2+ Removal from Water via an Cation Exchange Membrane

2012 ◽  
Vol 253-255 ◽  
pp. 954-959
Author(s):  
De Hua Xie
Keyword(s):  
Removal Efficiency ◽  
Retention Time ◽  
Hydraulic Retention Time ◽  
Removal Rate ◽  
Potassium Ions ◽  
Inlet Concentration ◽  
Experimental Conditions ◽  
External Voltage ◽  
Initial Concentration ◽  
Exchange Membrane

The removal of Cu2+ in water via an ion-exchange membrane under no external voltage condition was studied in the research, and effects such as Cu2+ concentration, concentration of compensation potassium ions, water stirring speed, temperature and hydraulic retention time (HRT) on the removal efficiency of Cu2+ were also investigated. The results showed that when the initial concentration of bivalent ion Cu2+ was 0.0787mmol/L （5mg/L）, under the experimental conditions of the water temperature at 25 °C , the HRT was 6h, the hydraulic mixing speed was 600±25rpm, and the concentration of the compensation ion K+ was 10 times as that of Cu2+, and the removal efficiency of Cu2+ could be achieved 85%. In addition, using the same equipments, when the inlet concentration of Cu2+ increased to 0.787mmol/L (50mg/L), the removal efficiency would be decreased to 76%; while the ratio of concentration of compensation potassium ions to that of inlet Cu2+ is larger than 20, the removal efficiency would not change significantly as the ratio continued increasing; the removal efficiency would be decreased to 60% when lowering the stirring speed to 300±25rpm; the removal efficiency would be decreased to 68% when lowering the temperature to 15+1 °C; the removal rate was no significant change when the hydraulic retention time (HRT) from 6h to 12h.

Removal of bisphenols by slow sand filtration

2009 ◽  
Vol 9 (3) ◽  
pp. 263-268 ◽  
Author(s):  
K. Katayama-Hirayama ◽  
S. Arai ◽  
T. Kobayashi ◽  
H. Matsuda ◽  
Z. Luo ◽  
...  
Keyword(s):  
Removal Rate ◽  
Molecular Orbital Calculation ◽  
Photocatalytic Reaction ◽  
Sand Filtration ◽  
Removal Rates ◽  
Sand Filter ◽  
Slow Sand Filtration ◽  
Initial Concentration ◽  
Slow Sand Filter ◽  
High Removal Rate

A compensating effect in the reduction of bisphenols (BPs) has been shown using biodegradation in slow sand filtration and advanced photocatalysis. We tried to remove 8 kinds of BP by slow sand filtration. Removal rates of BPA, BPB, BPE, BPF, BPS, thiobisphenol (TBP), and dihydroxybenzophenone (DHB) indicated a high removal rate up to more than 90% at an initial concentration of 100 μg/L, whereas the removal rate of BPP was only 30%. We also examined removal of BPs by Pt-loaded porous photocatalyst under visible light irradiation. Removal rates of BPA, BPB, BPE, BPF, BPP, and TBP showed high removal rates up to more than 90% at an initial concentration of 10 mg/L. Removal of BPS and DHB was relatively low at 20% and 30%, respectively. Removal of BPP was low in slow sand filtration, but Pt-loaded photocatalyst removed BPP effectively. Removal of BPS was low with Pt-loaded photocatalyst, but slow sand filtration removed BPS effectively. The combination of a slow sand filter and Pt-loaded photocatalyst may be helpful to degrade BPs. The magnitude of decomposition of BPs by photocatalytic reaction may be related to electrophilic frontier density. But the degradability of BPs in slow sand filtration is not the same as that in photocatalytic reaction with Pt-loaded titanium dioxide. The biodegradability of BPs by slow sand filtration cannot be explained by molecular orbital calculation.

Oxidation of polycyclic aromatic hydrocarbons by ozone in the presence of sand

2001 ◽  
Vol 43 (5) ◽  
pp. 349-356 ◽  
Author(s):  
H. Choi ◽  
Y.-Y. Kim ◽  
H. Lim ◽  
J. Cho ◽  
J.-W. Kang ◽  
...  
Keyword(s):  
Removal Rate ◽  
Oh Radicals ◽  
Ozone Decomposition ◽  
Oh Radical ◽  
Soil Slurry ◽  
Experimental Conditions ◽  
Polycyclic Aromatic ◽  
Soil Media ◽  
The Given ◽  
Catalytic Ozone

A series of soil slurry experiments was performed to investigate the characteristics of PAHs removal by ozone in various conditions. Gaseous ozone was bottled into the aqueous phase in the presence of soil contaminated by PAHs. The effects of soil media, OH radical scavengers, ozone dosage, and humic acid were examined at the given experimental conditions. There exists a substantial difference in the removal of PAH according to the types of soil media tested. Baked sand showed the highest removal efficiency compared to the others. The descending order of removal rate was: BS&gt;S&gt;GB. This is considered to be due to the OH radical effect produced by catalytic reactions of ozone with the reactive site on the and. This is qualitatively proved by the experiment of scavenging OH radicals using tert-butanol. The comparison of half-lives of ozone in sand and glass bead columns further supports this hypothesis. It was found that about 22% of enhancement of phenanthrene destruction was accomplished by OH radicals produced by the catalytic ozone decomposition. The rate of ozone consumption for the phenanthrene oxidation was obtained as 1.88 mg/mgO3/min.

Photocatalytic Degradation of Bisphenol A in Aqueous Suspensions of Titanium Dioxide

2012 ◽  
Vol 433-440 ◽  
pp. 172-177 ◽  
Author(s):  
Chen Zhong Jia ◽  
Qiao Yan Qin ◽  
Yan Xin Wang ◽  
Cai Xiang Zhang
Keyword(s):  
Aqueous Solution ◽  
Titanium Dioxide ◽  
Kinetic Model ◽  
Bisphenol A ◽  
Photocatalytic Degradation ◽  
Rate Constant ◽  
Removal Rate ◽  
Mercury Vapor ◽  
Initial Concentration ◽  
Photocatalytic Removal

Photocatalytic degradation of bisphenol A in aqueous solution by UV-TiO2 was studied in self-made photocatalysis reactor. The results showed that BPA was degraded effectively in UV-TiO2 photocatalysis system, and the processe followed Langmuir-Hinshelwood kinetic model. When TiO2 was dosed at 1.0 g/L, air amount was 1.2 L/min, BPA initial concentration was 10 mg/L with pH=5.5, and irradiated by a 15 W low pressure mercury vapor discharge lamp, the removal rate of BPA was up to 97%, and BPA was completely removed in 80 min when pH≥9.5; The photocatalytic removal rate constant was strongly related to the above factors.

Enhanced Photocatalytic Degradation of Antibiotic and Hydrogen Production by Iron Doped Cerium(IV) Oxide

2021 ◽  
Vol 21 (5) ◽  
pp. 3099-3106
Author(s):  
Yang Hsu ◽  
Joy Thomas ◽  
Chang Tang Chang ◽  
Chih Ming Ma
Keyword(s):  
Aqueous Solution ◽  
Hydrogen Production ◽  
Photocatalytic Degradation ◽  
Removal Rate ◽  
Emerging Contaminant ◽  
Total Removal ◽  
Initial Concentration ◽  
The Poor ◽  
Initial Ph ◽  
Pl Emission

Norfloxacin (NF) is an emerging antibiotic contaminant due to its significant accumulation in the environment. Photocatalytic degradation is an effective method for removing emerging contaminant compounds in aqueous solution; however, it is not commonly applied because of the poor solubility of contaminant compounds in water. In this study, a photocatalytic degradation experiment was carried out on NF using a self-made ceria catalyst. At an initial concentration of NF of 2.5 mg L−1, the dosage of CeO2 was 0.1 g L−1 photocatalyst in water, and the initial pH of the NF solution was 8.0. With a reaction time of 180 min, the total removal rate of NF could reach 95%. Additionally, the studies on hydrogen production show that the maximum hydrogen production with 2% Fe–CeO2 can reach 25,670 μmol h−1 g−1 under close to 8 W of 365 nm, a methanol concentration of 20%, and a catalyst dose of 0.1 g L−1 photocatalyst in water. Furthermore, the intensities of photoluminescence (PL) emission peaks decreased with increased Fe-doped amounts on CeO2, suggesting that the irradiative recombination seemed to be weakened.

Brewing Spent Diatomite as Adsorbents for Cu2+ Removal from Aqueous Solution

2014 ◽  
Vol 1010-1012 ◽  
pp. 523-527
Author(s):  
Ya Mei Wen ◽  
Hong Hui Teng
Keyword(s):  
Aqueous Solution ◽  
Adsorption Capacity ◽  
Adsorption Process ◽  
Copper Ions ◽  
Removal Rate ◽  
Order Reaction ◽  
Second Order Reaction ◽  
Initial Concentration ◽  
Adsorptive Removal ◽  
Initial Ph

Brewing spent diatomite (BSDT), a beer industrial by-product, was used for the adsorptive removal of copper ions from an aqueous solution. The results show that The removal rate of Cu2+decreased from 67.2% to 2.8% with decreasing initial pH from 6 to 2; the adsorption capacity decreased proportionally with an increasing amount of BSDT-800, but the removal efficiency of Cu2+increased with an increasing amount of adsorbent; the adsorption uptake at equilibrium (qe) increases from 9.9 mg/g to 34.1 mg/g with increasing initial concentration from 10 mg/L to 50 mg/L at 293K; the adsorption process of Cu2+onto BSDT-800 can be described by second-order reaction kinetics.

Sign in / Sign up

Export Citation Format

Share Document