Person: ERKEN, ESRA
Loading...
Email Address
Birth Date
Research Projects
Organizational Units
Job Title
Last Name
ERKEN
First Name
ESRA
Name
19 results
Search Results
Now showing 1 - 10 of 19
Publication Open Access Rapid decolorization of textile wastewater by green synthesized iron nanoparticles(IWA PUBLISHING, 2018-01-29) ERKEN, ESRA; Ozkan, Z. Y.; Cakirgoz, M.; Kaymak, E. S.; Erdim, E.The effectiveness of green tea (Camellia sinensis) and pomegranate (Punica granatum) extracts for the production of iron nanoparticles and their application for color removal from a textile industry wastewater was investigated. Polyphenols in extracts act as reducing agents for iron ions in aqueous solutions, forming iron nanoparticles. Pomegranate extract was found to have almost a 10-fold higher polyphenolic content than the same amount of green tea extract on a mass basis. However, the size of the synthesized nanoparticles did not show a correlation with the polyphenolic content. 100 ppm and 300 ppm of iron nanoparticles were evaluated in terms of color removal efficiency from a real textile wastewater sample. 300 ppm of pomegranate nanoscale zero-valent iron particles showed more than 95% color removal and almost 80% dissolved organic carbon removal. The degradation mechanisms are is considered to be adsorption and precipitation to a major extent, and mineralization to a minor extent.Publication Metadata only A novel approach in nzvi synthesis: reducing agent hydrazine recovery from deammonification wastewater(2021-09-08) ERKEN, ESRA; KOCAMEMİ, BİLGE; ERKEN E., KOCAMEMİ B., HÜR C.Publication Metadata only Atıksular ve atıksu arıtma çamurları ile Covid-19 takibi: Türkiye örneği, Türk Müşavir Mühendisler ve Mimarlar Birliği(2021-10-01) KOCAMEMİ, BİLGE; ERKEN, ESRA; KOCAMEMİ B., kurt h., ERKEN E., SAATÇI A. M.Publication Metadata only Nanoscale zero valent iron enhanced mainstream anammox application : a long-term evaluation with real sewage(2022-09-11) KOCAMEMİ, BİLGE; ERKEN, ESRA; KOCAMEMİ B., ERKEN E., kurt h.Publication Metadata only Assessment of green tea-enabled iron/calcined bentonite nanocomposites for phosphate removal and recovery(2022-10-01) ERKEN, ESRA; Hür C., ERKEN E.© 2022 Elsevier Ltd.We suggest using green tea enabled iron nanoparticles supported on calcined bentonite (G-nZVI/B) to remove and recover phosphate from synthetic wastewater. The nanocomposites are proposed as an eco-innovative adsorbent material for wastewater treatment plants. Adsorption columns packed with this novel nanocomposite would help overcome the footprint obstacle of wastewater treatment plants in a cost-effective way. We assessed the effect of various iron (Fe) /calcined bentonite (Cal-B) mass ratios (2 g Cal-B/2 g Fe, 2 g Fe, 2 g Cal-B/0.56 g Fe) and Fe/Green tea extract (GT) volumetric ratios (1/1, 1/0.5, 1/0.1) in 9 different nanocomposites (G-nZVI/B). The nanocomposites were characterized using BET, SEM, TEM, FT-IR, XRD, and XPS. The recipe for the optimized nanocomposite composition was found as follows: NC2 (Fe: 2 g, Calcined bentonite: 2 g, Fe/Green tea extract: (1/0.5) (V/V)). TEM analysis demonstrated that size of the iron nanoparticles (INPs) was within the range of 8-30 nm for NC2. Adsorption isotherms and kinetic models were carried out with the optimized nanocomposite under the following conditions: Room temperature; adsorbent dosage = 5 g/L; initial phosphate concentration: 10-900 mg/L, and contact time = 5-1500 min. The results revealed that the maximum adsorption capacity was 58.60 mg/g using Sips model (R2 = 0.959), and the adsorption rate constant was 23.017 mg/(g.min) using Elovich model (R2 = 0.971). Chemisorption was suggested to be the major mechanism of phosphate removal from an aqueous solution. The adsorption and recovery efficiencies were determined to be 98.60% and 53.48% using 1 g of NC2 with 50 mg/L initial phosphate concentration.Publication Metadata only Overcoming challenges in mainstream Anammox applications: Utilization of nanoscale zero valent iron (nZVI)(ELSEVIER, 2019) KOCAMEMİ, BİLGE; Erdim, Esra; Ozkan, Zeynep Yucesoy; Kurt, Halil; Kocamemi, Bilge AlpaslanAlthough Anammox process is a proven technology for sidestream nitrogen removal, the process faces challenges for mainstream applications in sewage treatment plants (STPs). The aim of this study was to investigate the effect of zero valent iron nanoparticles (nZVI) on process performance to eliminate confronts for mainstream applications. An SBR (sequencing batch reactor) system was fed with various nZVI concentrations (0.04-5000 ppb) within 310 days of operation. Ammonium (NH4+N) and nitrite (NO2-N) removal rates showed 58% increase in daily measurements and 73% increase in instant measurements. Specific Anammox Activity (SAA) was noticeably higher on the days the system was exposed to nZVI compared to the unexposed days. EPS secretion, which enhances granulation of Anammox bacteria was favored by nZVI. Despite lower sludge retention time (SRT) values, the fraction of Anammox bacteria in total bacteria reached to 91-92% implying a boosting effect of nZVI on growth rate of Anammox bacteria. High Resolution Melting (HRM) analyses showed that four distinct clades were present in the reactor. (C) 2018 Elsevier By. All rights reserved.Publication Metadata only Wastewater-Based Epidemiology (WBE) Studies for Monitoring of Covid-19 Spread(Springer International Publishing, 2022-01-01) KOCAMEMİ, BİLGE; ERKEN, ESRA; KOCAMEMİ B., Kurt H., ERKEN E., SAATÇI A. M.Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) started in Wuhan, China, in December 2019 and was announced as a worldwide pandemic spread by WHO on March 11, 2020. The countries have started to monitor surveillance of SARS-CoV-2 through medical tests. However, people with no or very light symptoms are usually not medically tested or never hospitalized, and their test results missed. In March 2020, it was recognized that the urine and feces of all infected people contain SARS-CoV-2. After that, wastewater-based epidemiology studies have gained significant importance around the world. This chapter aims to describe the basics of wastewater-based epidemiology (WBE) studies, the current situation in the world together with the post-Covid-19 approaches. Additionally, the major challenges in Covid-19 WBE studies are discussed.Publication Metadata only Recovery of Phosphate from Aqueous Solutions Using Supported Engineered Nanoparticles(2020-10-26) ERKEN, ESRA; ERKEN E., HÜR C.Publication Metadata only A revisit of pressure drop-flow rate correlations for packed beds of spheres(ELSEVIER SCIENCE BV, 2015) ERKEN, ESRA; Erdim, Esra; Akgiray, Omer; Demir, IbrahimA large number of correlations can be found in the literature for the calculation of pressure drop caused by fluid flow through packed beds. New correlations continue to be proposed and there appears to be no general agreement regarding which correlation is the most accurate. In this work, experiments have been carried out with water using glass spheres of nine different sizes, varying from 1.18 mm to 9.99 mm. For each size, experiments were repeated with at least two different porosities. A total of 38 correlations from the literature have been evaluated and a uniform notation was established to facilitate the comparison of the correlations. While the Ergun equation remains the most widely-used correlation, the data collected in this work shows that it should not be used above Re-m approximate to 500. A simple new equation (f(v) = 160 + 2.81Re(m)(0.904)) is proposed to represent the data collected in this work. The new equation yields the smallest mean error among all the correlations considered here. While a substantial amount of the data collected in this work involved D/d(p) ratios less than 10, the correlations that fit the current data best do not have any wall effect correction terms. (C) 2015 Elsevier B.V. All rights reserved.Publication Metadata only Atıksu bazlı epidemiyoloji çalışmaları ile covid-19 yayılımının incelenmesi(Tarım ve Orman Bakanlığı Türkiye Su Enstitüsü, 2022-02-01) KOCAMEMİ, BİLGE; ERKEN, ESRA; Kocamemi B., Erken E.Bu yayın, atıksu bazlı epidemiyoloji kavramını tanıtmak ve bu kapsamda SUEN koordinasyonunda ülkemiz genelinde yürütülen "Covid-19 yayılımının atıksularda SARS-CoV-2 analizleri ile takibi" çalışmalarının metodolojisi ve çalışmalar kapsamında edinilen bilgi ve tecrübeyi yerli ve yabancı uzmanlarla paylaşmak üzere hazırlanmıştır.