Herein, multiwalled carbon nanotube-based Fe3O4 nano-adsorbents (Fe3O4@MWCNT) were synthesized by ultrasonic reduction method. The synthesized nano-adsorbent (Fe3O4@MWCNT) exhibited efficient ...sonocatalytic activity to remove Maxilon Blue 5G, a textile dye, and present in a cationic form, in aqueous solution under ultrasonic irradiation. The magnetic nano-adsorbent particles were characterized by high-resolution transmission electron microscopy (HR-TEM), transmission electron microscopy (TEM), Raman spectroscopy and X-ray diffraction (XRD). Some important parameters such as nano-adsorbent dosage, solution pH, initial dye and H2O2 concentration, reaction time, ultrasonic power and temperature were tested to determine the optimum conditions for the elimination of Maxilon Blue 5G dye. The reusability results showed that Fe3O4@MWCNT nano-adsorbent has a decrease of about 32.15% in the removal efficiency of Maxilon Blue 5G under ultrasonic irradiation after six times reuse. Additionally, in order to reveal the sufficient kinetic explanation, various experiments were performed at different temperatures and testing three kinetic models like the pseudo-first-order, pseudo-second-order and intraparticle diffusion for removal adsorption process of Maxilon Blue 5G using Fe3O4@MWCNT nano-adsorbent. The experimental kinetic results revealed that the adsorption process of Maxilon Blue 5G in the aquatic mediums using sono-Fenton method was found to be compatible with the intraparticle diffusion. Using kinetic models and studies, some activation parameters like enthalpy, entropy and Gibbs free energy for the adsorption process were calculated. The activation parameters indicated that Fe3O4@MWCNT nano-adsorbent could be used as an effective adsorbent for the removal of Maxilon Blue 5G as a textile dye and the adsorption process of Maxilon Blue 5G with Fe3O4@MWCNT nano-adsorbent is spontaneous.
In this study, content analyses of the products obtained by pyrolysis and extraction of walnut shells were performed with some advanced analytical methods such as GS-MS, LC/MS-MS, and FTIR. In ...LC-MS/MS analyses. The presence of phenolic compounds in the pyrolysis liquid and extract liquid of walnut shells was determined using 41 standards. The obtained LC-MS/MS analysis results were compared, and it was found that the type and amount of phenolic compounds in the extracted liquid were more than the type and amount of phenolic compounds in the pyrolysis liquid. As a result of 41 phenolic standards investigations, the presence of a total of 10 phenolic compounds in liquids was detected and 2 of these compounds were detected in the pyrolysis liquid and 8 in the extracted liquid. As phenolic compounds, catechin (770.75 µg/g extract), hydroxy benzaldehyde (140.78 µg/g extract), and vanillic acid (114.95 µg/g compounds) were detected in the walnut extract. The existence of the compounds was supported by FTIR analyses of liquids obtained as a result of two different processes. By GC-MS analysis, linoleic acid methyl ester (44.01%), stearic acid methyl ester (14.93%), palmitic acid methyl ester (24.67%), linolenic acid and methyl ester compounds were detected in walnut shell extract liquid. GC-MS analysis of the pyrolysis liquid showed that compounds such as stearic acid methyl ester (18.97%), palmitic acid methyl ester (18.10%), o-xylene (12.17%), and o-ethyl toluene (8.14%) were formed as a result of pyrolysis. The findings revealed that walnut shell pyrolysis liquid product and extract contain very different phenolic, acid, and ester compounds. A concrete result was revealed about the use of the products obtained in this study in different areas.
In this study, slow pyrolysis of oak woods was carried out in a fixed bed tube reactor at four different temperatures ranging from 100 °C to 400 °C and at 5 °C/min speed time intervals. The ...compositions of the produced bio-tar and bio-oils were determined in detail using FT-IR, GC-MS, HPLC, and NMR devices. Several pyrolysis parameters were carried out to reveal the distribution of pyrolytic products under different pyrolysis temperatures (100–400 °C) and times (1–4 h). During the slow pyrolysis process, oak wood started to decompose to form organic volatile products at a set temperature of 100 °C and reached a maximum yield of volatile products at around 400 °C. GC-MS analyses revealed that different valuable components such as furans, phenolic compounds, carbonyls, linear, aromatic compounds, acids, and hydrocarbons have been formed. Based on the experimental results of the pyrolysis, it has been detected that the temperature and time interval are very effective parameters in the conversion of oak wood to the amount of liquid product.
Bimetallic Pt/Co loaded on GO adsorbance was produced following a series of simple hydrothermal methods. The produced bimetallic Pt/Co loaded GO material was used in the maxilon blue 5G removal (MB ...5G) and investigated its adsorption studies. The adsorption studies on removal of MB 5G using the bimetallic Pt/Co loaded on GO material were carried out performing different experimental conditions like ultrasonic irradiation time (1-120 min), temperature (24-55 oC), initial MB 5G concentration (0.7.10-5- 1.5.10-5 M), and pH (4- 10) to detect optimum removal conditions. The reaction kinetics were investigated by pairing the so-called first-order pseudo-second-order and intraparticle diffusion in the adsorption process study. In addition, enthalpy, entropy and Gibbs free energy, and thermodynamic activation functions were investigated in order to understand the adsorption mechanism. These data showed that the bimetallic Pt/Co loaded on GO material can be used as an effective nano adsorbent for the removal of MB 5G as an organic pollutant in an aquatic medium.
Bimetalik Pt/Co’nin GO üzerine yüklenmiş adsorbent bir seri hidrotermal metod ile sentezlendi. Elde edilen adsorbance maxilon blue 5G (MB 5G)’inin giderilmesinde kullanıldı ve adsorbsiyon çalışmaları incelendi. MB 5G’inin Pt/Co yüklü GO material ile yapılan adsorbsiyon çalışmaları farklı deneysel durumlarda olan ultrasonic ışıma zamanı (1-120 min), sıcaklık (24-55 oC), başlangıç MB 5G konstrasyonu (0.7.10-5- 1.5.10-5 M), ve pH (4- 10) gibi deneysel koşullar altında yapıldı. Kinetik reaksiyonlar birinci dereceden, ikinci dereceden ve intrapartikül düfüzyonu metodları ile incelendi. Buna ilaveten, entalpi, entropi, Gibbs serbest enerjisi ve termodinamik aktivasyon fonksiyoları aktivasyon mekanizmasını tespit etmek için incelendi. Elde edilen sonuçlar ile bimetallik Pt/Co’nin GO üzerine yüklenmiş adsorbent MB 5G organik boyasının giderilmesinde etkin bir şekilde kullanılabileceği sonucuna varıldı.
In this paper, we report the preparation of a new Fe3O4/SSIP/GO composite film for the purification of methylene blue dye from solution media. The preparation process of composite film was carried ...out to improve the interaction between the inner part of the sunflower stalk (SSIP) and surface matrix using magnetite/Graphene Oxide (Fe3O4/GO) minerals at weight ratios (0.2/4/0.2:w/w/w). The characterizations of as-developed Fe3O4/SSIP/GO composite film was successfully carried out by some advanced techniques such as FT-IR, SEM, and TGA analyses. Adsorption kinetic studies were evaluated in three different aspects as a pseudo-first-order model, pseudo-second-order model, and intraparticle diffusion-type model. Based on the R2 results, it was seen that the Pseudo-second order kinetic model (0.999) acted more harmoniously than the pseudo-first-order (0.960) and intra-particle diffusion technique models (0.974). In the light of these findings, it can be said that the prepared Fe3O4/SSIP/GO composite film used for removal of methylene blue dye can be considered as a promising material
Bor bileşiklerinin üretiminde kullanılan Uleksit çok önemli bir bor mineralidir. Bu çalışmada hidrateedilmiş uleksit minerali ve orginal mineralinin borik asit çözeltisindeki kinetik parametreleri ...incelenmiştir. DTAdiyagramına göre 170 oC’ye kadar mineral yapısında değişim olmadığı görülmüştür. Bu sıcaklık aralığında çözünmekinetiğinin arttığı gözlendi. SEM görüntülerinden 170 oC’ye kadar mineral gözeneklerinde açılmaların arttığı, busıcaklıktan sonra ise azaldığı gözlemlendi. Orijinal uleksite ait kinetik parametreler değerlendirildi. Mineralin borikasitteki çözünme kinetiği aşağıda ki gibi bulundu;1-(1-X)-1 = 2.02(Rp)-1,013CA0 0,4579(S.L-1)-0650(M.S)0,0545e-2649,12T-1.t
Ulexite used in the production of boron compounds is an important mineral. In this work, the kineticparameters of dehydrated ulexite mineral and orginal ulexite in boric acid solution were investigated. According tothe DTA diagram, it was seen that the mineral did not change the structure until around 170 oC. It was observed thatthe dissolution kinetics increased to this temperature. In the SEM images, it was observed that the number of poresin the mineral was increased until 170 oC and afterwards number of pores was decreased. The kinetic parametersof the original ulexite were evaluated. Study indicates that the dissolution kinetics model in the boric acide wasfound as below;1-(1-X)-1 = 2.02(Rp)-1,013CA0 0,4579(S.L-1)-0650(M.S)0,0545e-2649,12T-1.t
Nowadays, boron and its derivatives are widely used in industrial and technological areas. Boron minerals are the main sources for obtaining pure boron chemicals in the usage of different ...applications such as the defense industry, health, industry, kitchen equipments, etc. In this paper, for the first time, it has been reported the dissolution behaviors and kinetics parameters of ulexite in the boric acid solution. To solve ulexite by boric acid is important, because boric acid as a solvent prevents the formation of impurities, and therfeore our study is a first in the literature. In this context, the dissolution of the ulexite has been investigated under various experimental parameters such as temperatures, acid concentration, solid/liquid ratio, particle size, dissolution rate, and stirring speed. The experimental findings shown that the dissolution kinetics of ulexite increase with an increase in temperature and acid concentration and a decrease in particle size, but decrease with mixing speed in the acid. Moreover, the dissolution of ulexite in boric acid and activation energy were evaluated. As a result, it was found that the dissolution kinetics were compatible with the chemical control model and the activation energy was 22.024 kJ mol-1.
Spirogyra gratiana transeau alga was liquefied in organic solvents with and without catalyst in a cylindrical reactor at temperatures of 493, 513, and 533 K under supercritical conditions. The ...liquefied compounds were extracted with diethyl ether and benzene using an extraction procedure. The product yields in supercritical methanol, ethanol, and acetone were found to be 15.5, 23.7, and 34.4% at 533 K, respectively. The highest conversion to liquid products was obtained in supercritical ethanol with 10% sodium hydroxide as catalyst at the same temperature in the catalytic runs. Main chemical compounds present in the liquid product obtained in acetone without catalyst at 533 K were analyzed and characterized by gas chromatography-mass spectrometry (GC-MS).
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