The study was aimed at determining the effect of chemical pretreatment on copper(II) biosorption by
Marrubium globosum subsp.
globosum leaves. The uptake capacity of the biomass was increased by ...chemical pretreatment when compared with the raw biomass. The results of biosorption experiments, carried out at the conditions of 50
mg
l
−1 initial metal concentration and pH 5.5, showed that pretreating the biomass with alkali solutions (laundry detergent, sodium hydroxide and sodium bicarbonate, 0.5
M) improved the biosorption capacity of biomass (45.90, 45.78 and 43.91%, respectively) compared with raw biomass. Pretreatment with sulfuric and nitric acid solutions, 0.5
M, increased the biosorption capacity of biomass by 11.82 and 10.18%, respectively, while there was no considerable change in the biosorption capacity of biomass (0.35%) after pretreatment with formic acid solution, 0.5
M. Furthermore, sodium chloride and calcium chloride, 0.5
M, pretreatments resulted in the improvement in biosorption capacity of biomass (31.38 and 26.69%, respectively). FT-IR analysis revealed that hydroxyl and carboxyl functional groups were mainly responsible for copper(II) biosorption.
Denim production wastewater is an industrial wastewater with a high organic pollutant content. The aim of this study was to improve a cost-effective method via solar panel integration to the photo ...Fenton process (PFP) and photo electrochemical Fenton process (PEFP) for removing high chemical oxygen demand (COD) from denim production wastewater. To determine process parameter values, the double criterial optimization option was used. The results that maximized the COD removal efficiency and minimized the operating cost of two oxidation processes were determined by response surface methodology (RSM). Optimum operation conditions for the PFP process were 3.18 initial pH, 2.3 g/L Fe2+ concentration, and 27 g/L H2O2 concentration while they were 3.00 initial pH, 27.06 A/m2 current density, and 28.16 g/L H2O2 concentration for PEFP. At the optimum conditions, COD and the total organic carbon (TOC) removal efficiency of PFP were 85% and 61%, respectively. They were determined as 90% and 73% in PEFP. Carbon oxidation state (COS) and average oxidation state (AOS) parameters were used to obtain the biodegradation capability of organic materials. The biodegradability capability of wastewater was observed as high after the Fenton processes. As a result of the optimization of technical parameters, total operating cost was obtained as USD 14.62/m3 (USD 4.25/kgCODremoved) in PFP and USD 13.79/m3 (USD 3.73/kgCODremoved) in PEFP. After the integration of the photovoltaic solar panel to the processes, the total operating cost of PFP and PEFP decreased in a ratio of 61% and 64%, respectively.
In this study, Chemical Oxygen Demand (COD) removal efficiency from wood processing wastewaters by Fenton Process (FP) and Photo Electro Fenton Process (PEFP) were examined. Important operating ...parameters such as pH, Fe+2 concentration/(amper for PEFP), H2O2 concentration and reaction time were optimized. Optimum operation conditions of the FP were pH 3.5, 1.4 gr/L Fe2+ concentration and 50 gr/L H2O2 concentration and 150 min. reaction time while they were pH 3.00, 9.99 mA/cm2 current density and 70 gr/L H2O2 concentration and 150 min reaction time in PEFP. At the optimum conditions, COD removal efficiency of FP and PEFP was 91% and 99%, respectively. Sludge production of FP was 20% higher than PEFP at the optimum conditions.
Çalışmada, denim ürün işleme atıksularının hibrit Elektrokoagülasyon (EK) ve Elektrooksidasyon (EO) Prosesleri ile arıtımı incelenmiştir. pH, akım yoğunluğu ve elektroliz süresi gibi işletme ...parametrelerinin KOİ (Kimyasal Oksijen İhtiyacı) ve TÇK (Toplam Çözünmüş Katı) giderimi üzerindeki etkileri belirlenmiştir. pH değerinin 7,48, akım yoğunluğunun 120 A/m2 ve elektroliz süresinin 49,5 dakika olduğu Al (Alüminyum) elektrotlarının kullanıldığı EK prosesi ile >% 65 KOİ ve % 51 TÇK giderimi sağlanmıştır. Aynı koşullarda, EO işleminin KOİ ve TÇK için Ti (Titanyum)/PÇ (Paslanmaz Çelik) elektrotları ile giderim verimleri sırasıyla % >70 ve % 45 olarak bulunmuştur. Optimum koşullarda EK/EO hibrit prosesinin renk giderim verimi % 84 (436 nm), % 93 (525 nm), % 97 (620 nm) olarak elde edilirken, EK ve EO prosesinin enerji tüketimi sırasıyla 14,26 kWsa/m3 ve 22,71 kWsa/m3 olarak tespit edilmiştir. Ayrıca, istatistiksel analiz sonucunda elde edilen R2 ve R2adj değerlerinin 1'e yakın olması, deney sonuçlarının ve istatistiksel çıkarımların uyumlu olduğunu ve işlem parametrelerinin etkilerinin belirlenmesinde Box-Behnken istatistiksel tasarımının etkili olduğunu göstermiştir.
In this study, removal of suspended solids (SS) and turbidity from marble processing wastewaters by electrocoagulation (EC) process were investigated by using aluminium (Al) and iron (Fe) electrodes ...which were run in serial and parallel connection systems. To remove these pollutants from the marble processing wastewater, an EC reactor including monopolar electrodes (Al/Fe) in parallel and serial connection system, was utilized. Optimization of differential operation parameters such as pH, current density, and electrolysis time on SS and turbidity removal were determined in this way. EC process with monopolar Al electrodes in parallel and serial connections carried out at the optimum conditions where the pH value was 9, current density was approximately 15
A/m
2, and electrolysis time was 2
min resulted in 100% SS removal. Removal efficiencies of EC process for SS with monopolar Fe electrodes in parallel and serial connection were found to be 99.86% and 99.94%, respectively. Optimum parameters for monopolar Fe electrodes in both of the connection types were found to be for pH value as 8, for electrolysis time as 2
min. The optimum current density value for Fe electrodes used in serial and parallel connections was also obtained at 10 and 20
A/m
2, respectively. Based on the results obtained, it was found that EC process running with each type of the electrodes and the connections was highly effective for the removal of SS and turbidity from marble processing wastewaters, and that operating costs with monopolar Al electrodes in parallel connection were the cheapest than that of the serial connection and all the configurations for Fe electrode.
This paper reports on removal and recovery of copper(II) ions from aqueous solutions under batch experimental conditions using NaOH-pretreated powdered leaves of
Marrubium globosum ssp.
globosum ...plant. Experimental results showed that pH was optimized at the value of 5.5 by 16.23
mg/g. The increasing metal concentration and temperature caused an increase in biosorption capacity and the process reached its equilibrium in 60
min. The result obtained from kinetic and isotherm studies resulted in better agreement with pseudo second-order kinetic and Langmuir isotherm models. Thermodynamic parameters revealed that the Cu
2+ biosorption by the biomass was an endothermic process. The higher desorption efficiency above 90% was obtained in case of using Na
2EDTA, K
4O
7P
2, HNO
3, HCl, and (NH
4)
2C
2O
4
·
H
2O solutions, individually. Reusability of the biomass was examined under consecutive biosorption–desorption cycles repeating five times. The most interesting finding of the study is the idea of utilizing the EDTA–Cu complex, which can be qualified as a residual from desorption processes, as a liquid chemical fertilizer in agricultural applications.
E. coli (Escherichia coli) is a bacterium found in human and animal intestines. These bacteria, which can enter the bloodstream through as anyway as the environment or food, can cause many diseases ...such as diarrhea, respiratory problems, and blood/urinary tract infections especially in human. Therefore, these bacteria have to be removed from drinking water sources by some inactivation methods. Conventional methods as chlorination, ozonation and UV inactivation methods are effective but the development of techniques that do not require the transportation and storage of chemicals and do not produce negative by-products and cost-effective is the basis of environmental engineering studies. In this study, the inactivation effectiveness of hybrid electrode connected electrochemical process as a new approach on E. coli was investigated. The connection system was experienced with Al/SS/SS as Anode/Cathode/Anode electrode. Simultaneously electrocoagulation (EC) and electrooxidation (EO) mechanism works together in this electrode connection system. The inactivation coefficients were determined by the GInaFiT (Geeraerd and Van Impe Inactivation Model Fitting Tool) modeling tool, which is a Microsoft Excel add-on and the model was statistically well fitted with Double-Weibull. 4D degradation of E. coli was achieved as 21 minutes at a current density of 0.3 A and an optical density (O.D.) of 0.21. It has been determined that hybrid electrode connected electro-disinfection process is an effective approach for the E.coli inactivation.
European Union member countries use the spectral absorption coefficient (SAC) method within the framework of the standards set in EN ISO 7887 in the analysis of the color parameter in industrial ...wastewaters. In the study, the color removal efficiency of the discharge wastewater of the yeast production industry was investigated as SAC unit by electrochemical process using titanium and stainless steel electrodes. The effects of operating parameters such as pH, current density and electrolysis time on the removal of SAC436, SAC525 and SAC620 color parameters were optimized by the Response Surface Method (RSM).
Avrupa Birliği üyesi ülkeler endüstriyel atıksularda renk parametresinin analizinde EN ISO 7887'de belirlenen standartlar çerçevesinde renklilik sayısı (RES) yöntemini kullanmaktadır. Çalışmada, maya üreten işletmenin deşarj atıksuyunun RES birimi olarak titanyum ve paslanmaz çelik elektrotlar kullanılarak elektrokimyasal prosesle renk giderim verimi araştırılmıştır. Akım yoğunluğu, pH ve elektroliz süresi gibi işletme parametrelerinin RES436, RES525 ve RES620 renk parametrelerinin giderimi üzerindeki etkileri Yanıt Yüzey Metodu (YYM) ile optimize edilmiştir.
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