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1

Polyoxometalate Intercalated MgAl-Layered Double Hydroxide for Degradation of Malachite Green

Hanifah Yulizah, Mohadi Risfidian, Mardiyanto, Lesbani Aldes

Ecological Engineering & Environmental Technology

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2023

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Vol. 24, iss. 2

109--119

EN

Improving the selectivity of photocatalysis of LDH pristine (MgAl-LDH) and LDH composite (MgAl-SiW12O40] and MgAl-[PW12O40]) was synthesized and used for degraded malachite green (MG). The effects of the amount of catalyst, pH value, and reaction times on degradation performance were discussed. MG degraded better composites than LDH pristine. The results indicated that MgAl-LDH was successfully synthesized by showing the peak diffractions at angles 10.39°(003), 20.17°(006), and 34.8°(009). Both kinds of attained MgAl-[SiW12O40] and MgAl-[PW12O40] had the typical structure of LDH that proved by appeared diffraction at 2θ angles 7.73°, 28.6°, 35.6° for MgAl-[PW12O40] and at 2θ angles 8.61°, 24.27°, 34.96° and 66.34° for MgAl-[SiW12O40]. The FTIR result indicates materials used for fifth regeneration, which confirmed the LDH composite structure. The photodegradation activity of MG for pristine MgAl LDH (56.1%), composites MgAl-Pw (84.6%) and MgAl-Si (87.8%), respectively. The successful ability of photodegradation process by the percentage of degradation on material LDH-polyoxometalate composite showed the increasing of photodegradation catalytic and the regeneration ability of LDH pristine.

2

Phosphoric Acid Treated Oil Palm Trunk Waste for Removal of Malachite Green – Kinetics and Isotherm Investigations

Zainon Abidin Zarifah Aisyah, Al-Amrani Waheeba Ahmed, Mohd Suah Faiz Bukhari, Ibrahim Shariff, Megat Hanafiah Megat Ahmad Kamal

Ecological Engineering & Environmental Technology

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2023

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Vol. 24, iss. 6

33--43

EN

Dyeing operations in industries like textiles, paper, and leather are significant contributors to environmental pollution due to the release of harmful dyes. The current study aimed to examine the use of oil palm trunk (OPT) treated with phosphoric acid (PAOPT) to remove malachite green (MG) dye from aqueous solutions through batch adsorption experiments. Spectroscopic and quantitative tests were used to characterise the PAOPT adsorbent. The effects of initial solution pH (3–6), PAOPT dosage (0.02–0.10 g), and adsorption duration (0–120 min) were studied. The adsorption rate of MG followed a pseudo-second-order kinetic model with a high regression correlation (R2 ) and a low chi-squared value (χ2 ). The single-layer adsorption of PAOPT for MG was determined to be 217.23 mg/g at a pH of 6, 0.02 g PAOPT mass, 20 min contact time, and 298 K. The percentage of MG desorption from the loaded PAOPT using distilled water and 0.01 M HCl was 0% and 19.65%, respectively, indicating the possible involvement of electrostatic interactions between the dye and PAOPT, π-π interaction and hydrogen bonding. The experimental results of the current study and the assessment with other stated adsorbents indicate that PAOPT could be used as a cost-effective alternative adsorbent for MG removal.

3

Utilization of Rambutan Peel as a Potential Adsorbent for the Adsorption of Malachite Green, Procion Red, and Congo Red Dyes

Hasanah Mauizatul, Juleanti Novie, Priambodo Aldi, Arsyad Fitri Suryani, Lesbani Aldes, Mohadi Risfidian

Ecological Engineering & Environmental Technology

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2022

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Vol. 23, iss. 3

148--157

EN

Bioadsorbent preparation from rambutan peel applied as adsorbent was characterized using FT-IR, SEM-EDS, BET and TG-DTA analysis. FTIR analysis showed the presence of specific cellulose compounds in the rambutan peel bioadsorbent, the rambutan peel bioadsorbent was amorphous, there were wavy and uneven pores in the morphology of the rambutan peel and had the highest elemental content of 74.3%, the surface area of the rambutan peel was 1.22 cm/g. The adsorption process was applied to malachite green, congo red, and procion red dyes with parameters such as pH, kinetics, isotherm and thermodynamics. Based on kinetic parameters, the adsorption process of malachite green, congo red, and procion red using rambutan peel tends to follow the pseudo second order kinetic model. The adsorption capacity achieved was 182.40 mg/g in procion red, 6.24 mg/g in congo red, and 11.73 mg/g in malachite green. The adsorption process takes place spontaneously which is indicated by a negative Gibs free energy value.

4

Effect of Water Parameters on Decolourization Efficiency of Organic Dyes by Dielectric Barrier Discharge Plasma

El Shaer Mohamed, Habib Mohamed, Mobasher Mona

Ecological Engineering & Environmental Technology

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2021

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Vol. 22, iss. 1

74--82

EN

Nonthermal plasma discharge is used for the decolourization of dyes used in textile industry. Two dyes were considered, namely methylene blue and malachite green in aqueous solution. Plasma was generated by a Pin-water surface DBD between a metal pin electrode placed in air and the surface of an aqueous dye solution filling a glass container. Active radicals, especially hydroxyl radicals, generated by plasma in air penetrated the aqueous dye solution and induced the oxidizing reactions leading to the dyeing material disintegration. The measurements of solution parameters, including pH, oxidation-reduction potential, and conductivity can help to optimize the plasma decolourization efficiency of the two dye solutions. It was found that the pH values of the two dye solutions decrease with the increasing plasma treatment time. This is accompanied by an increase of the oxidation-reduction potentials and conductivities. The concentration of hydrogen peroxide formed in the two dye solutions during plasma treatment was found to increase with the plasma treatment time. The decolourization efficiencies of the two dye solutions increase with plasma treatment time and can be related to the solution parameters, including reduction of the pH values, increase in the oxidation-reduction potentials as well as solution conductivities and increase of hydrogen peroxide during the plasma treatment time.

5

Effect of different sized multi walled carbon nanotubes on the barrier potential and trap concentration of malachite green dye based organic device

Sen Sudipta, Manik N. B.

Advances in Materials Science

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2020

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Vol. 20, nr 4(66)

16--26

EN

Present work shows effect of 8 nm diameter and 30 nm diameter multi walled carbon nanotubes (MWCNT) on the barrier potential and trap concentration of Malachite Green (MG) dye based organic device. MWCNTs are basically a bundle of concentric single-walled carbon nanotubes with different diameters. In this work, ITO coated glass substrate and aluminium have been used as front electrode and back electrode respectively and the spin coating method is used to prepare the MG dye based organic device. It has been observed that both barrier potential and trap concentration are in correlation. Estimation of both these parameters has been done from current-voltage characteristics of the device to estimate the trap energy and the barrier potential of the device. Device turn-on voltage or the transition voltage is also calculated by using current-voltage characteristics. In presence of 8 nm diameter MWCNT, the transition voltage is reduced from 3.9 V to 2.37 V, the barrier potential is lowered to 0.97 eV from 1.12 eV and the trap energy is lowered to 0.028 eV from 0.046 eV whereas incorporation of 30 nm diameter MWCNT shows reduction of transition voltage from 3.9 V to 2.71 V and a reduction of barrier potential and trap concentration from 1.12 eV to 1.03 eV and from 0.046 eV to 0.035 eV respectively. Presence of both 8 nm diameter and 30 nm diameter MWCNT lowers trap energy approximately to 39% and 24% respectively and lowers barrier potential approximately to 13% and 8% respectively. Estimation of barrier potential is also done by Norde method which shows lowering of the value from 0.88 eV to 0.79 eV and from 0.88 eV to 0.84 eV in presence of both 8 nm and 30 nm diameter multi walled carbon nanotubes respectively. Calculation of barrier potential from both the I-V characteristics and Norde method are in unison with each other. Indication of enhancement of charge flow in the device can be ascribed to the truncated values of barrier potential and trap energy.

6

Adsorption of malachite green and congo red dyes from water: recent progress and future outlook

Swan Ng Boon, Zaini Muhammad Abbas Ahmad

Ecological Chemistry and Engineering. S

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2019

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Vol. 26, nr 1

119--132

EN

Global concern on dyes-laden effluent has intensified over the years. Dyes are toxic, stable to light, and hardly oxidized and bio-degraded, hence causing severe physiological effects to living organisms. In water, dye hinders the light penetration for photosynthetic activity, consequently oxygen is deficient for respiration by aquatic creatures. Adsorption has been widely recognized as the effective removal strategy to abate dye wastewater. However, the quests to improve the adsorption efficiency are continuously sought through new adsorbents with special characters, while performing the removal process at optimum operating conditions. This short review aims to summarize the recent progress in adsorption studies of two commonly used industrial dyes, namely malachite green and congo red by various adsorbents. From the quoted studies, the oxidized mesoporous carbon yields a higher adsorption capacity of malachite green at 1265 mg/g, while Fe3O4@nSiO2@mSiO2 displays a greater capacity for congo red removal at 1429 mg/g. A superior adsorption relies not only on specific surface area but also the synergistic interactions of pore width and mesoporosity, surface chemistry, and operating conditions. The dyes properties and factors affecting the adsorption are also highlighted and discussed, with recommendations and future outlook.

7

Adsorption of methylene blue and malachite green from aqueous solutions on mesoporous carbon-nickel and carbon-zinc composites

Jedynak K.

Inżynieria i Ochrona Środowiska

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2017

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T. 20, nr 1

43--57

EN

In this work adsorption of methylene blue and malachite green on mesoporous carbon-nickel and carbon-zinc composites (ST-A-Ni, ST-A-Ni(NO3)2-imp and ST-A-Zn, ST-A-Zn(NO3)2-imp) were investigated. These materials were obtained by the soft-templating method in presence of various precursors containing nickel or zinc. Nanoparticles of nickel or zinc and solutions of nickel nitrate(V) or zinc nitrate(V) were used as a source of nickel and zinc. Low-temperature nitrogen adsorption isotherms were determined for investigated materials and they were used for porous structure parameters calculation. Obtained isotherms can be classified as IV-type in order to IUPAC classification. Adsorbents have large surface area SBET: 674 m2/g (ST-A-Ni), 651 m2/g (ST-A-Ni(NO3)2-imp) and 511 m2/g (ST-A-Zn), 654 m2/g (ST-A-Zn(NO3)2-imp), large total volume of pores Vt: 0.65 cm3/g (ST-A-Ni), 0.63 cm3/g (ST-A-Ni(NO3)2-imp) and 0.32 cm3/g (ST-A-Zn), 0.64 cm3/g (ST-A-Zn(NO3)2-imp). Participation of mesoporosity in the total porosity of carbon composites is from approx. 44% to approx. 78%. This means that studied carbons are in fact mesoporous materials, with considerable domination of mesoporosity over the microporosity. The exception is composite ST-A-Zn were the microporosity value is a little bit higher than mesoporosity. The mesopores dimension for the maximum of the distribution function (in the range of mesopores) was determined by Kruk-Jaroniec-Sayari (KJS) method. This dimension was approx. 7 nm for all investigated adsorbents. SEM photos confirmed the presence of ordered mesopores, particularly in materials obtained as a result of zinc nitrate impregnation. Also the presence of nickel nanoparticles, with different dimensions and shapes (ST-A-Ni), was confirmed by SEM photos. The concentrations of adsorbates, before and after adsorption, were determined by spectrophotometric method. Adsorption experiments were carried out at 25°C temperature. The adsorption equilibrium for investigated in this work mesoporous compositions (carbon-metal-composite - colorant solution) was settled after 90 minutes (ST-A-Ni(NO3)2-imp-MB and ST-A-Zn(NO3)2-imp-MB), after 120 minutes (ST-A-Ni-MB), after 240 minutes (ST-A-Ni-MG) and for the rest of investigated compositions after 360 minutes. The studies of adsorption process velocity showed that in most cases adsorption kinetics proceeded according to pseudo II-order reaction model. Only in one case according to pseudo I-order reaction model: for ST-A-Zn (malachite green). Obtained adsorption isotherms were substituted into the Langmuir equation and Freundlich equation. Adsorption process of methylene blue and malachite green on all studied carbon-metal composites proceed in accordance to adsorption model described by Langmuir equation. Adsorption ability of studied mesoporous carbon materials is significantly higher for methylene blue than for malachite green. The best adsorbent for methylene blue was carbon ST-A-Zn(NO3)2-imp (qm = 104.17 mg/g), the worst adsorbent was carbon ST-A-Zn (qm = 6.65 mg/g). In the case of malachite green the best adsorbent was carbon ST-A-Ni (qm = 58.82 mg/g) and the worst adsorbent was carbon ST-A-Zn (qm = 4.25 mg/g). On the basis of K constant from Langmuir equation the value of free enthalpy BG was calculated. Obtained values change in the range from –28.06 to –36.78 kJ/mol. Negative values of BG mean that investigated process is spontaneous.

PL

W pracy zbadano adsorpcję błękitu metylenowego i zieleni malachitowej na mezoporowatych kompozytach węglowo-niklowych oraz węglowo-cynkowych (ST-A-Ni, ST-A-Ni(NO3)2-imp oraz ST-A-Zn, ST-A-Zn(NO3)2-imp). Materiały te otrzymano metodą miękkiego odwzorowania w obecności różnych prekursorów zawierających nikiel lub cynk. Nanocząstek niklu lub cynku oraz roztworów azotanu(V) niklu lub azotanu(V) cynku użyto jako źródeł niklu lub cynku. Dla badanych adsorbentów wyznaczono niskotemperaturowe izotermy adsorpcji azotu, które posłużyły do obliczenia parametrów struktury porowatej. Otrzymane izotermy można zaliczyć do IV typu zgodnie z klasyfikacją UPAC. Adsorbenty charakteryzują się dużą powierzchnią właściwą SBET: 674 m2/g (ST-A-Ni), 651 m2/g (ST-A-Ni(NO3)2-imp) oraz 511 m2/g (ST-A-Zn), 654 m2/g (ST-A-Zn(NO3)2-imp), dużą całkowitą objętością porów Vt: 0,65 cm3/g (ST-A-Ni), 0,63 cm3/g (ST-A-Ni(NO3)2-imp) oraz 0,32 cm3/g (ST-A-Zn), 0,64 cm3/g (ST-A-Zn(NO3)2-imp). Udział mezoporowatości w całkowitej porowatości kompozytów węglowych wynosi od ok. 44% do ok. 78%. Oznacza to, że rzeczywiście badane węgle są mezoporowate ze znaczną przewagą mezoporowatości nad mikroporowatością, z wyjątkiem kompozytu ST-A-Zn, który ma nieco bardziej rozwiniętą mikroporowatość. Wymiar mezoporów dla maksimum funkcji rozkładu (w przedziale mezoporów) wyznaczono metodą Kruka-Jarońca-Sayari (KJS). Dla wszystkich badanych adsorbentów wymiar ten wynosił ok. 7 nm. Zdjęcia SEM potwierdziły występowanie uporządkowanych mezoporów, szczególnie w materiałach otrzymanych w wyniku impregnacji azotanem cynku, a także obecność na powierzchni węgla nanocząstek np. niklu o różnych wymiarach i kształtach (ST-A-Ni). Stężenia adsorbatów przed i po adsorpcji wyznaczano metodą spektrofotometryczną. Badania adsorpcyjne prowadzono w temperaturze 25oC. Równowaga adsorpcyjna dla badanych w pracy układów mezoporowaty kompozyt węglowo-metaliczny - roztwór barwnika ustaliła się po 90 minutach (ST-A-Ni(NO3)2-imp-MB i ST-A-Zn(NO3)2-imp-MB), po 120 minutach (ST-A-Ni-MB), po 240 minutach (ST-A-Ni-MG) oraz dla pozostałych czterech przypadków po 360 minutach. Badania szybkości procesu adsorpcji wykazały, że w większości przypadków kinetyka adsorpcji przebiegała zgodnie z modelem reakcji pseudo II-rzędu, w jednym tylko przypadku zgodnie z modelem pseudo I-rzędu: ST-A-Zn (zieleń malachitowa). Otrzymane izotermy adsorpcji podstawiono do równania Langmuira i równania Freundlicha. Proces adsorpcji błękitu metylenowego oraz zieleni malachitowej na wszystkich badanych kompozytach węglowo-metalicznych zachodzi zgodnie z modelem adsorpcji opisanym przez równanie Langmuira. Zdolność adsorpcyjna badanych mezoporowatych materiałów węglowych jest znacznie większa w stosunku do błękitu metylenowego niż zieleni malachitowej. Najlepszym adsorbentem w stosunku do błękitu metylenowego był węgiel ST-A-Zn(NO3)2-imp (qm = 104,17 mg/g), a najsłabszym węgiel ST-A-Zn (qm = 6,65 mg/g). W przypadku zieleni malachitowej najlepszym adsorbentem był węgiel ST-A-Ni (qm = 58,82 mg/g), a najsłabszym węgiel ST-A-Zn (qm = 4,25 mg/g). Na podstawie stałej K z równania Langmuira obliczono wartość entalpii swobodnej BG. Otrzymane wartości zmieniają się w granicach od –28,06 do –36,78 kJ/mol. Ujemne wartości BG świadczą o tym, że badany proces to proces samorzutny.

8

Activated Carbon Loaded N, S co-doped TiO2&enspNanomaterial and Its Dye Wastewater Treatment

Kamalakkannan J., Chandraboss V. L., Prabha S., Senthilvelan S.

International Letters of Chemistry, Physics and Astronomy

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2015

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Vol. 47

147--164

EN

Activated carbon (AC) loaded nitrogen and sulfur (N, S) co-doped TiO2 &ensp nanomaterial (AC-N-STiO2) was prepared by precipitation method. AC-N-S-TiO2&enspmaterial was characterized by Scanning Electron Microscopy (SEM) with Energy Dispersive X-ray analysis (EDX), X-ray diffraction (XRD), Fourier Transform - Infrared (FT-IR), Photoluminescence (PL) and atomic force microscopy (AFM) analysis. Photodegradation and decolorization of Malachite green (MAG) and Methyl green (MEG) by using TiO2,N-S-TiO2 &enspand AC-N-S-TiO2under UV-light irradiation has been carried out. The photocatalytic activity of the AC-N-S-TiO2&enspwas higher than that of the undoped and N, S-doped TiO2,The hydroxyl radical analysis - Fluorescence technique with coumarin has been discussed. The photodegradation of MEG was well described by analyzed to be pseudo-first order according to the Langmuir-Hinshelwood representation, the high quantum yield set up to be calculated, stability and reustability of nanomaterial. AC-N-S-TiO2 &enspact as a promising photocatalyst for dye wastewater treatment under UV-light irradiation.

9

Photocatalytic degradation of malachite green dye using doped and undoped ZnS nanoparticles

Tolia J., Chakraborty M., Murthy Z. V. P.

Polish Journal of Chemical Technology

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2012

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Vol. 14, nr 2

16-21

EN

In the present study, ZnS nanoparticles were prepared using the mechanochemical method. The ZnS nanoparticles prepared were doped with different concentrations of manganese using metal acetate and manganese acetate by mechanochemical method. The as-prepared particles were characterized using X-ray diffraction (XRD) and transmission electron microscopy (TEM). The photocatalytic activity of the prepared nanoparticles samples, in the photocatalytic degradation of malachite green, had been investigated. The nanoparticles were photo induced, generating hole transfer for photocatalytic activity. The photodegradation of malachite green was observed at different pH (2-5) values, dye concentrations (10-100mg/L) and amount of ZnS nanoparticles (1-2.5 g/L). About 95% degradation of dye was observed on the addition of 2 g/L ZnS in 50 mg/L dye solution after 90 minutes illumination at 125 W. Degradation has been increased up to 99% using UV/nanoparticles/H2O2 (50 mL/L) combined process. The degradation efficiency was also compared using Mn doped ZnS nanoparticles (Zn1-x MnxS, where x = 0.01, 0.22 and 0.3). Maximum of 97% degradation was observed with 0.01% concentration of Mn. Kinetics study and performance of UV/ZnS, UV/ZnS/H2O2, UV/doped ZnS processes were evaluated to compare the efficiency of different processes.

10

Solid phase extraction using a column with a monolithic molecuraly imprinted epoxy resin-based polymeric stationary phase : HPLC determination of malachite green in fish and water samples

Sui W., Hailong L., Zhiyong G., Huina Z., Yanling T., Danyi W.

Chemia Analityczna

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2009

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Vol. 54, No. 6

1339-1353

EN

A column with a novel monolithic molecularly imprinted polymer (MlP)-based stationary phase with malachite green (MG) as template molecules was prepared. The synthesized MIP was characteri/cd by IR and SEM. Extraction conditions on MIPs were optimized. MG and some other compounds were employed for selectivity tests. River water samples were spiked with MG at the concentration 20-500 ng mL-1 extraction was performed using a MISI'E column and detection was accomplished by HPLC. The achieved recoveries were in the range 95.06-100.13%; relative standard deviation was 0.025-6.63%. MG concentrations in three natural water and fish samples were 2.65,2.60,2.36 and 5.63 ng mL-1, respectively.

PL

Sporządzono kolumnę z nową falą stacjonarną opartą na monolitycznym polimerze z odwzorowaniem molekularnym (MIP), w którym w charakterze szablonu użyto zieleni malachitowej (MG), /syntetyzowany MIP scharakteryzowano za pomocą IR i SEM. Zoptymalizowano warunki ekstrakcji na MIP. Do badań selektywności użyto MG i inne związki. Efektywność ekslracji porzy zastosowaniu kolumn MISPE i próbek wody rzecznej z dodatkiem MG (20-500 ng mL-1) badano stosując do oznaczenia metodę HPLC. Odzyski wahały się w granicach 95-100% ze względnym odchyleniem stasndardowym 0.025-6.6%. Stwierdzono stężenia MG w trzech opróbkach wód naturalnych i w ekstrakcie z ryby w wysokości odpowiednio: 2.65. 2.60. 2,36 i 5,63 ng mL-1.

11

Pozostałości zieleni malachitowej i jej metabolitów w tkankach ryb

Mitrowska K.

Analityka : nauka i praktyka

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2008

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nr 3

9-12