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Sub-microparticles have many applications in different fields today. In this study, it is aimed to develop hydrophobic microparticles as an alternative to existing methods and to determine the 17β-estradiol adsorption performance of this adsorbent to purify the 17β-estradiol hormone which is found as an endocrine disruptor in environmental waters with high capacity and low cost. In this study, l-phenylalanine containing Poly(HEMA-MAPA) microparticles were synthesized by microemulsion polymerization and used as adsorbent. Microparticles were characterized by Fourier transform infrared spectroscopy (FT-IR) and scanning electron microscope (SEM) methods. The size of the Poly(HEMA-MAPA) microparticles used was measured as 120–200 nm. Specific surface area and elemental analysis studies were also conducted. While the surface area of the particles was found to be a very high value of 1890 m2/g, the amount of incorporation of MAPA into the polymeric structure was calculated as 0.43 mmol/g. Adsorption studies were carried out in the batch system under different ambient conditions (17β-estradiol concentration, temperature, ionic intensity). The adsorption capacity of Poly(HEMA-MAPA) microparticles was calculated to be 98.4 mg/g. Isotherm models for adsorption interaction were investigated deeply, and it was determined that the adsorption mechanism is suitable for Langmuir isotherm.

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Sediment, nehirlerin, göllerin, koyların, haliçlerin ve okyanusların tabanında yer alan yeryüzü katmanıdır. Dünyanın en büyük soda gölü olması, eşine rastlanmayacak büyüklükte ve güzellikte dipten yükselen güncel karbonat sütunları içermesi ve su seviyesinde yaşanan değişimler, Van Gölü'nü dünyanın en ilginç göllerinden biri yapar. Bu çalışmada Van Gölünden alınan doğal sediment ve asitle (HNO3) aktive edilmiş sedimentlerin ağır metal (Cr 3+) ile ilişkisi batch adsorpsiyon tekniği kullanılarak saptanmaya çalışılmıştır. Farklı konsantrasyonlardaki krom (Cr 3+) iyonlarının ve pH'ın adsoprsiyon prosesi üzerine etkisi araştırılmıştır. Langmuir, Freundlich, Dubinin-Radushkevich (D-R) ve Temkin adsorpsiyon izotermleri hesaplanmıştır. Hem doğal sediment (DS) hem de asitle modifiye edilmiş sedimentin (MS) Langmuir adsorpsiyon izoterm modeline uyum sağladığı bulunmuştur. Bununla birlikte hem doğal adsorbent hem de asitle modifiye edilmiş adsorbentin termodinamik parametreleri hesaplanmış, ΔG° < 0 değerinin adsoprsiyon prosesinin kendiliğinden gerçekleştiğini göstermiştir. Doğal sedimentin yüzey alanı 7.512 m²/g, asit ile aktive edilmiş sedimentin yüzey alanı 79.456 m²/g tespit edilmiş olup aktivasyon işlemi ile çok yüksek bir yüzey alanı elde edilmiştir. Giles adsorpsiyon izoterm sistemine göre H tipi eğriye uyduğu görülmüştür.

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Antibiotics are among the most critical environmental pollutant drug groups. Adsorption is one of the methods used to eliminate these pollutants. In this study, activated carbon was produced from pumpkin seed shells and subsequently modified with KOH. The adsorbent obtained through this procedure was used to remove ciprofloxacin from aqueous systems. Fourier Transform-Infrared Spectroscopy (FT-IR), Scanning Electron Microscopy (SEM), elemental, X-ray Photoelectron Spectroscopy (XPS), Brunauer–Emmett–Teller (BET) and Zeta analyses were used to characterize the adsorbent. The surface area, in particular, was found to be a very remarkable value of 2730 m2/g. The conditions of the adsorption experiments were optimized based on interaction time, adsorbent amount, pH and temperature. Over 99% success was achieved in removal operations carried out under the most optimal conditions, with an absorption capacity of 884.9 mg·g−1. In addition, the Langmuir isotherm was determined to be the most suitable model for the adsorption interaction.

Pesticides are among the most dangerous developing toxins since they are very hazardous to the environment and threaten human health. In this study, researchers successfully manufactured surface-modified magnetic diatomite (m-DE-APTES) and used them as a sorbent to extract endosulfan from an aqueous solution. There is no other study like it in the scholarly literature, and the results are astounding. Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), energy dispersive X-ray (EDX), electron spin resonance (ESR), and surface area measurements were used to analyze magnetic diatomite particles with surface modification. According to the analysis results, magnetic diatomite has a wide surface area and a porous structure. Furthermore, m-DE-APTES has a higher endosulfan adsorption capacity (97.2 mg g−1) than raw diatomite (DE) (16.6 mg g−1). Adsorption statistics agree with Langmuir adsorption isotherm (R2 = 0.9905), and the adsorption occurred spontaneously at −2.576 kj mol−1 in terms of ΔGo. Finally, m-DE-APTES are a viable alternative adsorbent for removing pesticides from aqueous solutions.