scholarly journals Research on the Degradation of Oxacillin in Water by Strong Ionization Discharge

2021 ◽  
Author(s):  
Rongjie Yi ◽  
Qi Zhang ◽  
Chengwu Yi
Keyword(s):  
Aqueous Solution ◽  
Removal Efficiency ◽  
Theoretical Basis ◽  
Input Voltage ◽  
Initial Concentration ◽  
Treatment Conditions ◽  
Effective Removal ◽  
Initial Ph ◽  
Strong Ionization Discharge ◽  
By Products

The degradation of oxacillin in aqueous solution by strong ionization dielectric barrier discharge (DBD) was explored. The effects of input voltage, initial pH, initial concentration of solution and hydroxyl (·OH) inhibitor on the removal efficiency of OXA were investigated. The results showed that the removal efficiency of OXA with initial concentration of 20mg/L reached 91.5% under the optimal treatment conditions of 3.8 kV and 7.3 pH. With the higher voltage and the lower initial concentration, the removal effect was better. The pH of the solution has little effect on the removal efficiency, and the removal effect is the best in neutral aqueous solution. The inhibition effect of TBA was stronger than that of CO32- and HCO3-. Moreover, ·OH was the main active substance in the process of strong ionization discharge, which played a major role in the removal of OXA. In addition, two main by-products were identified, the transformation pathways including hydroxylation (+16 Da), decarboxylation (-44 Da) were observed. This study provided a theoretical basis for the effective removal of antibiotics in water by strong ionization discharge.

scholarly journals Effective removal of lead (II) ions by dead calcareous skeletons: sorption performance and influencing factors

2016 ◽  
Vol 74 (7) ◽  
pp. 1577-1584 ◽  
Author(s):  
Ai Phing Lim ◽  
Zufarzaana Zulkeflee ◽  
Ahmad Zaharin Aris
Keyword(s):  
Removal Efficiency ◽  
Contact Time ◽  
Low Cost ◽  
High Concentration ◽  
Initial Concentration ◽  
Ph Adjustment ◽  
Equilibrium Time ◽  
Factors Influencing ◽  
Effective Removal ◽  
Initial Ph

Dead calcareous skeletons (CSs) as low-cost adsorbents were studied to remove lead ions (Pb (II)) in an aqueous solution. Factors influencing the efficiency of CSs were evaluated by adsorbent size, contact time, initial concentration, dosage concentration and pH. The optimum CS size for removal of Pb (II) was 710 μm at an equilibrium time of 720 min. The best dosage of CS was 10 g/L for a 99% removal efficiency without pH adjustment. Pb (II) ions were effectively removed in the initial pH of the metal solution. CS was able to remove a high concentration (100 mg/L) of Pb (II) at a removal efficiency of 99.92% and at an adsorption capacity of 13.06 mg/g. Our results demonstrated the potential of CS as a metal adsorbent in the aqueous phase with a high-removal efficiency and distinct physical characteristics.

Comparative Bio-sorption of Cadmium and Nickel Ions from Aqueous Solution onto Fibers of Date Palm using Fluidized Bed Column

2019 ◽  
Vol 70 (5) ◽  
pp. 1507-1512
Author(s):  
Baker M. Abod ◽  
Ramy Mohamed Jebir Al-Alawy ◽  
Firas Hashim Kamar ◽  
Gheorghe Nechifor
Keyword(s):  
Aqueous Solution ◽  
Heavy Metal ◽  
Metal Ions ◽  
Fluidized Bed ◽  
Removal Efficiency ◽  
Heavy Metal Ions ◽  
Date Palm ◽  
Operating Conditions ◽  
Initial Concentration ◽  
Bed Height

The aim of this study is to use the dry fibers of date palm as low-cost biosorbent for the removal of Cd(II), and Ni(II) ions from aqueous solution by fluidized bed column. The effects of many operating conditions such as superficial velocity, static bed height, and initial concentration on the removal efficiency of metal ions were investigated. FTIR analyses clarified that hydroxyl, amine and carboxyl groups could be very effective for bio-sorption of these heavy metal ions. SEM images showed that dry fibers of date palm have a high porosity and that metal ions can be trapped and sorbed into pores. The results show that a bed height of 6 cm, velocity of 1.1Umf and initial concentration for each heavy metal ions of 50 mg/L are most feasible and give high removal efficiency. The fluidized bed reactor was modeled using ideal plug flow and this model was solved numerically by utilizing the MATLAB software for fitting the measured breakthrough results. The breakthrough curves for metal ions gave the order of bio-sorption capacity as follow: Cd(II)]Ni(II).

scholarly journals Efficient Sequestration of Hexavalent Chromium by Graphene-Based Nanoscale Zero-Valent Iron Composite Coupled with Ultrasonic Pretreatment

2021 ◽  
Vol 18 (11) ◽  
pp. 5921
Author(s):  
Haiyan Song ◽  
Wei Liu ◽  
Fansheng Meng ◽  
Qi Yang ◽  
Niandong Guo
Keyword(s):  
Aqueous Solution ◽  
Removal Efficiency ◽  
Inhibitory Effect ◽  
Ultrasonic Cavitation ◽  
Zero Valent Iron ◽  
Ultrasonic Pretreatment ◽  
Nanoscale Zero Valent Iron ◽  
Passivation Layers ◽  
Initial Ph ◽  
Two Phases

Nanoscale zero-valent iron (nZVI) has attracted considerable attention for its potential to sequestrate and immobilize heavy metals such as Cr(VI) from an aqueous solution. However, nZVI can be easily oxidized and agglomerate, which strongly affects the removal efficiency. In this study, graphene-based nZVI (nZVI/rGO) composites coupled with ultrasonic (US) pretreatment were studied to solve the above problems and conduct the experiments of Cr(VI) removal from an aqueous solution. SEM-EDS, BET, XRD, and XPS were performed to analyze the morphology and structures of the composites. The findings showed that the removal efficiency of Cr(VI) in 30 min was increased from 45.84% on nZVI to 78.01% on nZVI/rGO and the removal process performed coupled with ultrasonic pretreatment could greatly shorten the reaction time to 15 min. Influencing factors such as the initial pH, temperature, initial Cr(VI) concentration, and co-existing anions were studied. The results showed that the initial pH was a principal factor. The presence of HPO42−, NO3−, and Cl− had a strong inhibitory effect on this process, while the presence of SO42− promoted the reactivity of nZVI/rGO. Combined with the above results, the process of Cr(VI) removal in US-nZVI/rGO system consisted of two phases: (1) The initial stage is dominated by solution reaction. Cr(VI) was reduced in the solution by Fe2+ caused by ultrasonic cavitation. (2) In the following processes, adsorption, reduction, and coprecipitation coexisted. The addition of rGO enhanced electron transportability weakened the influence of passivation layers and improved the dispersion of nZVI particles. Ultrasonic cavitation caused pores and corrosion at the passivation layers and fresh Fe0 core was exposed, which improved the reactivity of the composites.

scholarly journals Evaluation of removal efficiency of residual diclofenac in aqueous solution by nanocomposite tungsten-carbon using design of experiment

2017 ◽  
Vol 76 (6) ◽  
pp. 1466-1473 ◽  
Author(s):  
M. H. Salmani ◽  
M. Mokhtari ◽  
Z. Raeisi ◽  
M. H. Ehrampoush ◽  
H. A. Sadeghian
Keyword(s):  
Aqueous Solution ◽  
Removal Efficiency ◽  
Design Of Experiment ◽  
High Efficiency ◽  
Carbon Powder ◽  
Batch Adsorption ◽  
Effective Parameters ◽  
Initial Concentration ◽  
Carbon Nanocomposite ◽  
Maximum Removal

Wastewater containing pharmaceutical residual components must be treated before being discharged to the environment. This study was conducted to investigate the efficiency of tungsten-carbon nanocomposite in diclofenac removal using design of experiment (DOE). The 27 batch adsorption experiments were done by choosing three effective parameters (pH, adsorbent dose, and initial concentration) at three levels. The nanocomposite was prepared by tungsten oxide and activated carbon powder in a ratio of 1 to 4 mass. The remaining concentration of diclofenac was measured by a spectrometer with adding reagents of 2, 2′-bipyridine, and ferric chloride. Analysis of variance (ANOVA) was applied to determine the main and interaction effects. The equilibrium time for removal process was determined as 30 min. It was observed that the pH had the lowest influence on the removal efficiency of diclofenac. Nanocomposite gave a high removal at low concentration of 5.0 mg/L. The maximum removal for an initial concentration of 5.0 mg/L was 88.0% at contact time of 30 min. The results of ANOVA showed that adsorbent mass was among the most effective variables. Using DOE as an efficient method revealed that tungsten-carbon nanocomposite has high efficiency in the removal of residual diclofenac from the aqueous solution.

scholarly journals Acid Blue 25 Removal by using Electro-Persulfate Process

2020 ◽  
Author(s):  
Zeinab Ghorbani
Keyword(s):  
Aqueous Solution ◽  
Removal Efficiency ◽  
Salt Concentration ◽  
Dye Removal ◽  
Industrial Effluents ◽  
Sodium Persulfate ◽  
Initial Concentration ◽  
Acid Blue 25 ◽  
Sulfate Process ◽  
Acid Blue

This study aimed to investigate the efficiency of the electro-persulfate process in removing acid blue 25 from aqueous solution. In order to optimize the parameters, the OFAT method was used, and the effect of three main parameters, including pH, sodium persulfate salt concentration, and current intensity was investigated. According to the results, the optimal removal efficiency of 94% in 60 minutes was obtained under conditions of pH=5, the initial concentration of sodium persulfate=250 mg / L, and the current=500 mA. According to the results of this study, the electro-persulfate process sulfate process can be an efficient process for dye removal from industrial effluents.

Preparation of Visible Light Response K6SiW11O39SnII for Photocatalytic Degradation of Acid Brilliant Scarlet

2012 ◽  
Vol 476-478 ◽  
pp. 2005-2008
Author(s):  
Xiu Hua Zhu ◽  
Jia Huan Liu ◽  
Li Li Zhao ◽  
Peng Yuan Wang
Keyword(s):  
Aqueous Solution ◽  
Solar Radiation ◽  
Visible Light ◽  
Photocatalytic Degradation ◽  
Light Response ◽  
Photocatalytic Decomposition ◽  
Initial Concentration ◽  
Environmental Friendly ◽  
Visible Light Response ◽  
Initial Ph

Environmental friendly materials, K6SiW11O39SnⅡ(abbreviated as SiWSn), was synthesized, which is visible light response photocatalyst. The photocatalytic decomposition of Acid Brilliant Scarlet (abbreviated as ABS) aqueous solution with SiWSn was investigated using a broad spectrum of solar radiation. The results showed that the photocatalytic degradation efficiency of ABS with SiWSn was affected by the initial pH of ABS solution, the amount of SiWSn and the photolysis time. When the initial pH of ABS solution was 5, the initial concentration of that (20mL) was 3mg L-1, the concentration of SiWSn was 1.25g L-1, and it was irradiated 4h under the sunlight, the discoloration rate of which was 71.4%.

Adsorption of Nitrobenzene and Benzoic Acid from Aqueous Solution by All-Silica Zeolite Beta

2011 ◽  
Vol 183-185 ◽  
pp. 1378-1382 ◽  
Author(s):  
Qing Dong Qin ◽  
Jun Ma ◽  
Da Fang Fu
Keyword(s):  
Aqueous Solution ◽  
Benzoic Acid ◽  
Contact Time ◽  
Batch Reactor ◽  
Zeolite Beta ◽  
Reactor System ◽  
Equilibrium Isotherm ◽  
Initial Concentration ◽  
Initial Ph ◽  
Increasing Temperature

All-silica zeolite beta (BEA) was tested for the ability to remove nitrobenzene and benzoic acid from aqueous solution. The effect of contact time, temperature, initial concentration and initial pH were investigated in a batch reactor system. Adsorption of nitrobenzene decreased with increase in temperature. The equilibrium isotherm was L-shaped. Nitrobenzene adsorption was independent of pH. Adsorption of benzoic acid increased with increasing temperature from 5 °C to 22 °C and decreased with increasing temperature from 22°C to 32 °C. The equilibrium isotherm was approximately S-shaped. Benzoic acid adsorption was dependent of pH. At pH8.0, benzoic acid can also be adsorbed effectively. The results above confirmed that BEA had the potential to be utilized as relatively effective adsorbent for nitrobenzene and benzoic acid removal.

Destruction of EDTA by Bimetallic Al-Fe/O2 Process under Aqueous Room Temperature and Pressure Conditions

2013 ◽  
Vol 800 ◽  
pp. 555-559
Author(s):  
Xin Liu ◽  
Jin Hong Fan ◽  
Lu Ming Ma
Keyword(s):  
Aqueous Solution ◽  
Benzoic Acid ◽  
Removal Efficiency ◽  
Room Temperature ◽  
Ethylenediaminetetraacetic Acid ◽  
Oxidative Degradation ◽  
Hydroxybenzoic Acid ◽  
Mass Ratio ◽  
Initial Ph ◽  
Temperature And Pressure

Oxidative degradation of ethylenediaminetetraacetic acid (EDTA) in aqueous solution at room temperature and pressure by the bimetallic Al-Fe/O2 process, which was verified by the addition of benzoic acid as ·OH scavenger and the detection of para-hydroxybenzoic acid, was investigated. The results showed that the removal efficiency of EDTA, TOC and TN could be about 98%, 77.5% and 43% respectively after 3h reaction when the initial pH was 5. The effects of initial pH, concentration of EDTA, mass ratio of Al0 and Fe0 and Al-Fe loading were also investigated. Significantly, the bimetallic Al-Fe process exhibited higher reactivity than monometallic Fe0/Al0 process for the degradation of EDTA when the mass ratio of Al0 and Fe0 ranged from 0.11 to 2.97.

scholarly journals Removal of Cadmium from Industrial Wastewater using Electrocoagulation Process

2019 ◽  
Vol 26 (1) ◽  
pp. 24-34 ◽  
Author(s):  
Mohammed Alameen Salem ◽  
Najwa Majeed
Keyword(s):  
Heavy Metal ◽  
Removal Efficiency ◽  
Applied Voltage ◽  
Industrial Wastewater ◽  
Batch Reactor ◽  
Operating Parameters ◽  
Initial Concentration ◽  
Initial Ph ◽  
Electrocoagulation Process ◽  
Aluminum Electrodes

Cadmium is one of the heavy metal found in the wastewater of many industries. The electrocoagulation offers many advantages for the removal of cadmium over other methods. So the removal of cadmium from wastewater by using electrocoagulation was studied to investigate the effect of operating parameters on the removal efficiency. The studied parameters were the initial pH, initial concentration, and applied voltage. The study experiments were conducted in a batch reactor with  with two pairs of aluminum electrodes with dimension  and 2mm in thick with 1.5 cm space between them. The optimum removal was obtained at pH =7, initial concentration = 50 mg/L, and applied voltage = 20 V and it was 90%.

scholarly journals Electrochemical Removal of Copper Ion Using Coconut Shell Activated Carbon

2020 ◽  
Vol 20 (3) ◽  
pp. 530
Author(s):  
Nur Azza Azyan Muin ◽  
Hawaiah Imam Maarof ◽  
Nur Alwani Ali Bashah ◽  
Nor Aida Zubir ◽  
Rasyidah Alrozi ◽  
...  
Keyword(s):  
Activated Carbon ◽  
Removal Efficiency ◽  
Applied Voltage ◽  
Treatment Time ◽  
Copper Ion ◽  
Electrochemical Process ◽  
Coconut Shell ◽  
Initial Concentration ◽  
Initial Ph ◽  
Coconut Shell Activated Carbon

In this work, coconut shell activated carbon (CSAC) electrode was evaluated to remove copper ion via electrochemical processes. CSAC electrode and graphite were applied as the cathode and the anode, respectively. The reusability of the electrode, the effects of initial pH, applied voltage and initial concentration were studied. The electrochemical process was carried out for 3 h of treatment time, and the electrodes (anode and cathode) were separated by 1 cm. The results revealed that CSAC is proven as a reusable electrode to remove copper ion, up to 99% of removal efficiency from an initial concentration of 50 ppm after it had been used three times. From the observation, the removal efficiency was optimum at an initial pH of 4.33 (without any initial pH adjustment). The applied voltage at 8 V showed a higher removal efficiency of copper ion compared to at 5 V.

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