scholarly journals Phenol removal by enhanced electrocoagulation process with persulfate salt

Vestnik MGSU ◽  
2021 ◽  
pp. 1592-1598
Author(s):  
Sameh Abdelfattah Araby Ahmed ◽  
Elena S. Gogina

Introduction. Phenol is classified as priority pollutant. Phenol and its derivatives are stable in water, environmental contamination, and health concerns that are used as raw material in many chemical industries. This study investigated the removal of phenol by the reactivity of free sulfate radicals (SO4•–), activated by electrochemically generated Fe2+/Fe3+ ions which furthermore are evaluated to destroy phenol in aqueous solution. Materials and methods. In the present experimental study, electrocoagulation reactor by iron electrodes is used in the pre­sence of persulfate ions to phenol removing from aqueous solutions. In this regard, the effect of four independent variables including pH, electric current, persulfate dosage, and initial phenol concentration were studied on phenol removal. Results. The study determined the optimum conditions for maximum phenol removal using electro-persulfate process (EPS) as pH 3, 7.4 mM persulfate dosage, 27.78 mA/cm2 current density, and 100 mg/L initial phenol concentration at 30-min reaction time. The results showed that the efficiency of phenol removal was directly related to the initial persulfate dosage. In addition, the pH values, less than the phenol pKa, has slight effect onto the phenol removal. However, it was inversely correlated with a highly alkaline pH and higher phenol concentration. Conclusions. The study concluded that electro-persulfate process is an effective and robust process that can be used for handling of phenol containing wastewater.

2014 ◽  
Vol 2014 ◽  
pp. 1-8
Author(s):  
Xiao Chen ◽  
Yan Liang ◽  
Xuefei Zhou ◽  
Yanling Zhang

A novel non-photo-dependent semiconductor catalyst (CT) was employed to degrade phenol in the present pilot-scaled study. Effect of operational parameters such as phenol initial concentration, light area, and catalyst loading on phenol degradation, was compared between CT catalyst and the conventional photocatalyst titanium dioxide. CT catalyst excelled titanium dioxide in treating and mineralizing low-level phenol, under both mild UV radiation and thunder conditions of nonphoton. The result suggested that CT catalyst could be applied in circumstances when light is not easily accessible in pollutant-carrying media (e.g., particles, cloudy water, and colored water).


2013 ◽  
Vol 3 (2) ◽  
pp. 119-127 ◽  
Author(s):  
Papita Das Saha ◽  
Jaya Srivastava ◽  
Shamik Chowdhury

The efficacy of seashells as a new adsorbent for removal of phenol from aqueous solutions was studied by performing batch equilibrium tests under different operating parameters such as solution pH, adsorbent dose, initial phenol concentration, and temperature. The phenol removal efficiency remained unaffected when the initial pH of the phenol solution was in the range of 3–8. The amount of phenol adsorbed increased with increasing initial phenol concentration while it decreased with increasing temperature. The adsorption equilibrium data showed excellent fit to the Langmuir isotherm model with maximum monolayer adsorption capacity of 175.27 mg g−1 at pH 4.0, initial phenol concentration = 50 mg L−1, adsorbent dose = 2 g and temperature = 293 K. Analysis of kinetic data showed that the adsorption process followed pseudo-second-order kinetics. Activation energy of the adsorption process, calculated using the Arrhenius equation, was found to be 51.38 kJ mol−1, suggesting that adsorption of phenol onto seashells involved chemical ion-exchange. The numerical value of the thermodynamic parameters (ΔG0, ΔH0 and ΔS0) indicated that adsorption of phenol onto seashells was feasible, spontaneous and endothermic under the examined conditions. The study shows that seashells can be used as an economic adsorbent for removal of phenol from aqueous solution.


2017 ◽  
Vol 77 (2) ◽  
pp. 504-510 ◽  
Author(s):  
Tao Deng ◽  
Hongyu Wang ◽  
Kai Yang

Abstract Phenol is a toxic pollutant in many kinds of hypersaline industrial effluents that should be treated properly before discharged into water bodies. In this work, a halophilic strain which could utilize phenol as the sole source of carbon and energy was isolated. Based on 16S rRNA results, it was identified as a member of Citrobacter. The phenol biodegradation ability and cell growth of the strain was evaluated with the variation of initial phenol concentration and salinity. The effect of temperature and pH on phenol removal was also investigated. The results showed that the strain was capable of withstanding high phenol (up to 1,100 mg L−1) environment with varying salinity conditions (0–10% of NaCl). The optimal initial phenol concentration was 400 mg L−1, at which the average removal rates of phenol peaked at 10.8 mg L−1 h−1. The higher initial concentration of phenol could inhibit the microbial metabolism. The optimal temperature, pH, and salinity were 35 °C, 6.0, and 0%, respectively. Under these conditions, 400 mg L−1 of phenol could be completely degraded within 20 h. The high removal rates of phenol by the strain might provide an alternative for treating phenolic wastewaters containing high salinity.


2017 ◽  
Vol 76 (12) ◽  
pp. 3190-3194 ◽  
Author(s):  
Sevgi Ertuğrul Karatay ◽  
Gönül Dönmez ◽  
Zümriye Aksu

Abstract The use of microbial biomass as biosorbent for phenol removal has been extensively studied, but its removal by biosorption by thermophilic cyanobacterium Phormidium sp. has not been investigated to the best of our knowledge. In the present study, some important parameters for biosorption process were optimized, starting with testing the effects of different pH values ranging from 1 to 12, and then initial phenol concentrations of 45.1, 115.3, 181.4, 243.3, 339.9 mg/L on phenol uptake. The efficiency of removal from aqueous solution was higher within the pH 6–8 range, with the maximum of 100% at pH 7 after 24 hours of adsorption time. The highest specific rate was observed as 165.1 mg/g in the presence of 339.9 mg/l initial phenol concentration. The Freundlich adsorption models were fitted to the equilibrium data, which indicated that phenol ions were favourably adsorbed by Phormidium sp.


2019 ◽  
Vol 20 (1) ◽  
pp. 23-29
Author(s):  
Huda Adil Sabbar

The exploitation of obsolete recyclable resources including paper waste has the advantages of saving resources and environment protection. This study has been conducted to study utilizing paper waste to adsorb phenol which is one of the harmful organic compound byproducts deposited in the environment. The influence of different agitation methods, pH of the solution (3-11), initial phenol concentration (30-120ppm), adsorbent dose (0.5-2.5 g) and contact time (30-150 min) were studied. The highest phenol removal efficiency obtained was 86% with an adsorption capacity of 5.1 mg /g at optimization conditions (pH of 9, initial phenol concentration of 30 mg/L, an adsorbent dose of 2 g and contact time of 120min and at room temperature). The well-known Langmuir and Freundlich adsorption models were studied. The results show that the equilibrium data fitted to the Freundlich model with R2=0.9897 within the concentration range studied. The main objective of this study is finding the best mixing and conditions for phenol removal by adsorption via paper waste.


1992 ◽  
Vol 26 (9-11) ◽  
pp. 2191-2194 ◽  
Author(s):  
M. Fujita ◽  
M. Ike ◽  
T. Kamiya

The metabolic pathway of the phenol degradation in Pseudomonasputida BH was amplified by introducing the recombinant plasmid containing catechol 2,3 oxygenase gene isolated fron the chromosome of BH. This strain could degrade phenol and grow much faster than the wild strain at the phenol concentration of 100mg/L. This strain seems to accelerate the phenol removal rate if it is applied to the treatment of wastewater containing phenol.


2012 ◽  
Vol 454 ◽  
pp. 324-328
Author(s):  
Yan He ◽  
Ya Jing Liu ◽  
Yong Lin Cao ◽  
Li Xia Zhou

Infra-red absorption spectrometry, X-ray diffraction observations and characterization tests based on silicon molybdenum colorimetric method were used to investigate the optimal pH value controlling the stability of the silicic acid form. The experiment process was done by using sodium silicate as raw material. The results showed that the solution of silicate influenced the polymerization. The active silicic acid solution with a certain degree of polymerization was obtained by controlling the pH values.


2021 ◽  
Vol 410 ◽  
pp. 411-417
Author(s):  
Anastasia A. Zvereva ◽  
Vladimir A. Shunin ◽  
Roman S. Voinkov ◽  
Konstantin L. Timofeev

The article lays out the findings aimed to develop the fine silver powder production technique for electronics industry by selecting the variable parameters whereby a number of powder grades can be produced in the existing production environment (JSC “Uralelektromed”, Russia). The tests for significance of the parameters of silver recovery by ascorbic acid such as pH level of nitrate silver solution, dispersant flow rate, initial concentration of silver, mixing rate and solution temperature made it possible to choose optimum conditions to produce powders of 0.8-6.3 μm in particle size, of 3.0-4.2 g/cm3 in tapped density and with the specific surface area of 2300-4300 cm2/g. Crystalline silver of 99.98 % purity served as a raw material for obtaining silver powders.


2016 ◽  
Vol 19 (0) ◽  
Author(s):  
Ricardo Schmitz Ongaratto ◽  
Luiz Antonio Viotto

Summary The aim of this work was to separately evaluate the effects of pectinase and cellulase on the viscosity of pitanga juice, and determine the optimum conditions for their use employing response surface methodology. The independent variables were pectinase concentration (0-2.0 mg.g–1) and cellulase concentration (0-1.0 mg.g–1), activity time (10-110 min) and incubation temperature (23.2-56.8 °C). The use of pectinase and cellulase reduced the viscosity by about 15% and 25%, respectively. The results showed that enzyme concentration was the most important factor followed by activity time, and for the application of cellulase the incubation temperature had a significant effect too. The regression models showed correlation coefficients (R2) near to 0.90. The pectinase application conditions that led to the lowest viscosity were: concentration of 1.7 mg.g–1, incubation temperature of 37.6 °C and incubation time of 80 minutes, while for cellulase the values were: concentration of 1.0 mg.g-1, temperature range of 25 °C to 35 °C and incubation time of 110 minutes.


Author(s):  
Pranabendu Mitra ◽  
Kyu -Seob Chang ◽  
Dae-Seok Yoo

Kaempferol, a strong antioxidant, was extracted from Cuscuta reflexa (a medicinal plant) using supercritical CO2 and separated using thin-layer chromatography, column chromatography and HPLC analysis. A rotatable central composite design was used to determine the influence of process variables and arrive at optimal processing conditions in the supercritical CO2 extraction process of kaempferol. The kaempferol yield was effectively modelled as a function of the independent variables (temperature, time and pressure). The kaempferol yield increased with the increasing of temperature and time and decreasing of pressure of the supercritical CO2 extraction process. The predicted kaempferol yield at the optimum point was 52.92 µg/g and the optimum conditions were 50.7°C for 132.6 min and 15.9 MPa.


Sign in / Sign up

Export Citation Format

Share Document