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Abstrak :
Nanokomposit TiO2/CuO dengan variasi rasio Cu/Ti disusun menggunakan metode sol-gel. Sampel komposit dikarakterisasi dengan X-Ray Diffraction, Energy Dispersive X-Ray Spectroscopy, Field Emission Scaning, Brunauer-Emmett-Teller, UV-Visible Diffuse Reflectance Spectroscopy dan Electronic Spin Resonance Spectroscopy. Methylene blue digunakan sebagai model pewarna tekstil untuk mengevaluasi fotokatalitik, sonokatalitik dan fotosonokatalitik. Difraksi sinar-X dan dispersif energi analisis X-ray menegaskan bahwa hanya struktur monoklinik CuO dan struktur anatase TiO2 yang muncul di nanokomposit TiO2/CuO. Degradasi methylene blue menunjukkan bahwa penggabungan CuO di nanokomposit TiO2/CuO menunjukkan aktivitas fotokatalitik yang cukup tinggi, dan energi cahaya yang dapat dimanfaatkan lebih banyak dibandingkan TiO2 murni. Selain itu, degradasi methylene blue juga diselidiki menggunakan sistem sonokatalisis dan sistem fotosonokatalisis. Hasil penelitian menunjukkan bahwa semua data eksperimen mengikuti model pseudo-first order tapi laju konstanta fotosonokatalisis lebih tinggi dari proses fotokatalisis dan sonokatalisis individu masing-masing. Selain itu, kegiatan fotokatalitik, sonokatalitik dan fotosonokatalitik akan berkaitan dengan sifat struktural dan optik sampel. Mekanisme kegiatan katalitik akan dibahas.

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TiO2/CuO nanocomposite with different Cu/Ti ratios were prepared using sol-gel method. The obtained composite samples were characterized with X-Ray Diffraction, Energy Dispersive X-Ray Spectroscopy, Field Emission Scaning, Brunauer-Emmett-Teller, UV-Visible Diffuse Reflectance Spectroscopy and Electronic Spin Resonance Spectroscopy. Methylene blue was used as a model of textile dye to evaluate their photocatalytic, sonocatalytic and photosonocatalytic activities. X-ray diffraction and energy dispersive X-ray analysis confirmed that only monoclinic CuO and anatase TiO2 structures are present in TiO2/CuO nanocomposites. The degradation of methylene blue indicated that the incorporation of CuO in TiO2/CuO nanocomposite exhibited an appreciable higher photocatalytic activity, and more light energy could be utilized than pure TiO2. In addition, the degradation of methylene blue was also investigated using sonocatalysis and photosonocatalysis systems. The results showed that all experimental data followed the pseudo-first order model but the rate constant of the sonophotocatalysis is higher than the respective individual photocatalysis and sonocatalysis process. Furthermore, the photocatalytic, sonocatalytic and photosonocatalytic activities will be related to their structural and optical properties. The mechanism of catalytic activities will be discussed.

Abstrak :
ABSTRAK
Penelitian ini akan mensimulasikan temperatur transisi pada superkonduktor NdBa2Cu3O7-x. Superkonduktor NdBa2Cu3O7-x terdiri dari satu bidang CuO. Sumulasi temperatur transisi superkonduktor NdBa2Cu3O7-x dapat dipelajari dengan menggunakan model ASYNNNI. Dalam model ASYNNNI, oksigen di tempatkan pada bidang CuO secara acak. Kandungan oksigen yang diberikan akan mempengaruhi besarnya temperatur transisi. Temperatur transisi tertinggi terjadi pada superkonduktor NdBa2Cu3O7-x dengan kandungan oksigen 90% yaitu sekitar 30 K. Temperatur transisi tidak dihasilkan dalam simulasi dua bidang CuO, karena bahan ini tidak bersifat superkonduktor

Abstrak :
Metil ester asam lemak (Fatty Acid Methyl Ester = FAME) merupakan senyawa utama penyusun biodiesel dan bahan baku untuk surfaktan metil ester sulfonate (MES). Minyak kemiri sunan yang mempunyai kandungan minyak tinggi dalam setiap bijinya berpotensi menjadi bahan baku untuk produksi FAME. Kandungan asam lemak bebas (free fatty acid/FFA) dan asam lemak tak jenuh gandanya (asam α-eleostearat, C18: 3) yang tinggi dapat diminimalisir dengan esterifikasi dan reaksi adisi. Penelitian ini bertujuan menyintesis dan mengarakterisasi fotokatalis CuO/TiO2 untuk menurunkan kadar FFA dan jumlah asam lemak tak jenuh ganda (C18:3) dari minyak kemiri sunan dengan esterifikasi dan adisi secara simultan, mendapatkan kondisi operasi reaksi dan mendapatkan mekanisme reaksi prediksinya. Katalis CuO/TiO2 disintesis dengan cara impregnasi serbuk TiO2 P25 dengan larutan tembaga nitrat (Cu(NO3)2. 2H2O sebagai prekursor Cu dan dilanjutkan dengan kalsinasi. Hasil karakterisasi dengan (FESEM), Mapping, Energy Dispersive X-Ray (EDX), X-Ray Diffraction (XRD), Transmission electron microscopy (TEM) dan High resolution transmission electron microscopy (HRTEM) menunjukkan bahwa oksida tembaga (CuO) terdispersi dengan baik pada permukaan TiO2. Hasil X-Ray Photoelectron spectroscopy (XPS) menunjukkan bahwa Cu berada dalam bentuk senyawa CuO (Cu2+) sedangkan Ti dalam keadaan Ti4( TiO2.). Hasil karakterisasi ultra violet-vis diffuse reflectance spectroscopy (UV DRS) menunjukkan energi band gap dari semua sampel CuO/ TiO2 lebih kecil daripada TiO2 P25. Reaksi yang dilakukan dalam fotoreaktor di bawah paparan sinar UV ini mendorong terjadinya esterifikasi dan adisi FFA secara bersamaan. Penurunan FFA optimum pada kondisi kadar CuO/ TiO2 4%, waktu reaksi 4 jam, rasio molar minyak terhadap metanol 1:30, jumlah katalis 5% (b/b). Konversi FFA sekitar 59% dan kandungan akhir FFA masih lebih besar dari 2,5%.  Hasil karakterisasi gas chromatography mass spectroscopy (GCMS) menunjukkan bahwa reaksi adisi asam α-Eleostearat pada kondisi ini diperoleh konversi 100%. Meskipun kemampuan fotokatalis dalam penurunan FFA relatif rendah, namun penurunan ikatan rangkap asam α-Eleostearat (C18:3) sangat tinggi. Pengurangan ikatan rangkap ini merupakan sesuatu positif mengingat jumlah asam ±-Eleostearat dalam minyak kemiri sunan yang mencapai 41,8%.  Dengan adanya reaksi adisi yang berlangsung bersama dengan esterifikasi akan meningkatkan potensi minyak kemiri sunan sebagai bahan baku untuk FAME. Dalam disertasi ini, juga diusulkan mekanisme reaksi esterifikasi dan adisi secara bersamaan. ......Fatty acid methyl ester (FAME) is the main compound of biodiesel and raw material of methyl esther sulfonate (MES) surfactant. Kemiri sunan oil which has high oil content in its seed has high potential to be synthesized into FAME.  The high content of free fatty acid (FFA) and poly-unsaturated fatty acid (α-Eleostearic acid; C18:3) can be reduced by converting its FFA content through esterification and reducing its unsaturation number with an addition. The objectives of this research are to synthesize and characterized CuO/TiO₂ photocatalyst for reducing the free fatty acid (FFA) and poly-unsaturated fatty acid content simultaneously, to study the operation condition of reaction and to study the reaction mechanism prediction. The CuO/TiO2 catalyst was synthesized by the impregnation of TiO2 P25 powder with copper nitrate solution as a precursor and followed by calcination. The Field emission scanning electron microscopy (FESEM), Mapping, Energy Dispersive X-Ray (EDX), X-Ray Diffraction (XRD), Transmission electron microscopy (TEM) and High resolution transmission electron microscopy (HRTEM) results showed that Copper oxide was highly dispersed on the TiO2 surface. The X-Ray photoelectron spectroscopy (XPS) result showed that Cu is in the state of CuO (Cu2+) while Ti is in Ti4 (TiO2). The ultra violet-vis diffuse reflectance spectroscopy (UV-DRS) results shows that the energy band gap of CuO/TiO2 samples were lower than TiO2 P25. It was found that reaction in the presence of CuO/TiO2 in a photoreactor under UV irradiation can perform esterification and addition reaction of the FFA, simultaneously. The optimum reduction of the FFA was under condition of 4% loading CuO/TiO2, 4 hours reaction time, 30:1 (mole/mole) metanol to oil ratio, 5% (w/w) catalyst amount. The conversion of  FFA was at around 59% and the final FFA content still more than 2.5%. The gas chromatogram mass spectroscopy (GCMS) results showed that the addition reaction of α-Eleostearic acid simultaneously occured at 100% conversion.  Although the photocatalyst performance in  FFA reduction was relatively  low, but double bond reduction of α-Eleostearic acid (C18:3) was very high. The reduction of multiple double bond is consideres as positive poin due to the amount of α-Eleostearic acid is very high (about 41,8%). The addition occurred with esterification simultaneously will increase the potency of kemiri sunan oil as a FAME raw material.  The simultaneous esterification and addition reactions mechanism has been proposed.

Abstrak :
Nanohybrid iron oxide titanium dioxide copper oxide dengan tiga variasi molar 1 1 1 1 3 1 dan 1 5 1 telah disintesis menggunakan metode sol gel Pengukuran X Ray Diffraction XRD Field Emission Scanning Electron Microscopy FESEM Energy Dispersive X rays EDX UV Vis Spectroscopy dan Vibrating Sample Magnetometer VSM digunakan untuk menentukan sifat struktur morfologi nilai energy gap optik dan sifat magnetik dari sampel nanohybrid Pengujian aktivitas fotokatalitik sampel nanohybrid dilakukan dengan mengamati degradasi warna methylene blue MB dibawah pemaparan cahaya ultraviolet dan tampak Hasil menunjukkan keberadaan copper oxide seiring dengan peningkatan rasio molar titanium dioxide mempengaruhi aktivitas fotokatalitik nanohybrid Nanohybrid dengan rasio molar 1 5 1 menunjukkan aktivitas fotokatalitik yang paling baik untuk pemaparan dengan cahaya ultraviolet sedangkan untuk pemaparan dengan cahaya tampak didapatkan dengan rasio molar 1 1 1 Selain itu fotokatalis nanohybird dapat dipisahkan setelah proses reaksi menggunakan magnet eksternal Penambahan scavenger menunjukkan hole memiliki peranan penting dalam proses degradasi methylene blue ......Iron oxide titanium dioxide copper oxide nanohybrids with three different molar ratios 1 1 1 1 3 1 and 1 5 1 were successfully prepared by sol gel method X Ray Diffraction XRD Field Emission Scanning Electron Microscopy FESEM Energy Dispersive X rays EDX UV ndash Vis spectroscopy and Vibrating Sample Magnetometer VSM techniques were employed to determine the structure morphology optical gap energy and magnetic properties of the as prepared samples Photocatalytic examination of the nanohybrids was carried out using aqueous solution of methylene blue MB under ultraviolet and visible light irradiation The results demonstrate that the increase molar ratio of titanium dioxide and the addition of copper oxide to iron oxide titanium dioxide cooper oxide has remarkable influence on the photocatalytic activity The nanohybrids with 1 5 1 molar ratio has superior activity in degradation of MB under ultraviolet light while under visible light the maximum degradation is reached by sample with molar ratio 1 1 1 Furthermore the photocatalysts can be separated from the reaction system simply by applying an external magnetic Active species on photocatalytic activity were investigated by measuring the photocatalytic degradation in the presence of scavenger The results suggested that holes play the most important role in degradation of methylene blue.

Abstrak :
Nanokomposit ZnO/CuO dengan lima variasi molar ZnO:CuO (1:3, 1:1, 1:0.5, 1:0.3, dan 1:0.1) telah disintesis dengan menggunakan metode sol-gel. Pengukuran X-ray Diffraction (XRD), Energy Dispersive X-Ray (EDX), Field Emission Scanning Electron Microscopy (FESEM), nitrogen adsorption spectroscopy, Electron Spin Resonance (ESR), dan UV-Visible spectroscopy dilakukan untuk mengindentifikasi struktur, morfologi, luas permukaan, resonansi ion-ion, dan nilai celah energi dari nanokomposit. Aktivitas katalitik dari nanokomposit ZnO/CuO diuji dibawah pemaparan cahaya visible, ultraviolet, ultrasonik, dan gabungan antara visible/UV dengan ultrasonik dalam mendegradasi larutan pewarna methylene blue (MB). Hasil aktivitas katalitik dari nanokomposit ZnO/CuO menunjukkan aktivitas photosonocatalytic mempunyai performa lebih baik dibandingkan aktivitas photocatalytic dan sonocatalytic. Penambahan beberapa scavenger menunjukkan hole merupakan spesies aktif yang berperan paling penting dalam mekanisme katalitik.

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ZnO/CuO nanocomposites with five different ZnO:CuO ratios (1:3, 1:1, 1:0.5, 1:0.3 and 1:0.1) were prepared using sol-gel method. X-ray Diffraction (XRD), Energy Dispersive X-Ray (EDX), Field Emission Scanning Electron Microscopy (FESEM), nitrogen adsorption spectroscopy, Electron Spin Resonance (ESR) and UV-Visible spectroscopy were employed to investigate the structural, morphology, surface area, ions resonance and energy band gap of nanocomposites. The catalytic activity of ZnO/CuO nanocomposites were tested under visible light, ultraviolet light, ultrasound irradiation and the combination of visible/UV light with ultrasound irradiation on the degradation of methylene blue (MB) aqueous solution. The observed catalytic activity of nanocomposites shows that photosonocatalytic has better performance than photocatalytic and sonocatalytic activity. The addition of scavengers suggested that holes are the most important active species in the catalytic mechanism.

Abstrak :
Nanokomposit TiO2/CuO dengan variasi rasio Cu/Ti disusun menggunakan metode sol-gel. Sampel komposit dikarakterisasi dengan X-Ray Diffraction, Energy Dispersive X-Ray Spectroscopy, Field Emission Scaning, Brunauer-Emmett-Teller, UV-Visible Diffuse Reflectance Spectroscopy dan Electronic Spin Resonance Spectroscopy. Methylene blue digunakan sebagai model pewarna tekstil untuk mengevaluasi fotokatalitik, sonokatalitik dan fotosonokatalitik. Difraksi sinar-X dan dispersif energi analisis X-ray menegaskan bahwa hanya struktur monoklinik CuO dan struktur anatase TiO2 yang muncul di nanokomposit TiO2/CuO. Degradasi methylene blue menunjukkan bahwa penggabungan CuO di nanokomposit TiO2/CuO menunjukkan aktivitas fotokatalitik yang cukup tinggi, dan energi cahaya yang dapat dimanfaatkan lebih banyak dibandingkan TiO2 murni. Selain itu, degradasi methylene blue juga diselidiki menggunakan sistem sonokatalisis dan sistem fotosonokatalisis. Hasil penelitian menunjukkan bahwa semua data eksperimen mengikuti model pseudo-first order tapi laju konstanta fotosonokatalisis lebih tinggi dari proses fotokatalisis dan sonokatalisis individu masing-masing. Selain itu, kegiatan fotokatalitik, sonokatalitik dan fotosonokatalitik akan berkaitan dengan sifat struktural dan optik sampel. Mekanisme kegiatan katalitik akan dibahas.

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TiO2/CuO nanocomposite with different Cu/Ti ratios were prepared using sol-gel method. The obtained composite samples were characterized with X-Ray Diffraction, Energy Dispersive X-Ray Spectroscopy, Field Emission Scaning, Brunauer-Emmett-Teller, UV-Visible Diffuse Reflectance Spectroscopy and Electronic Spin Resonance Spectroscopy. Methylene blue was used as a model of textile dye to evaluate their photocatalytic, sonocatalytic and photosonocatalytic activities. X-ray diffraction and energy dispersive X-ray analysis confirmed that only monoclinic CuO and anatase TiO2 structures are present in TiO2/CuO nanocomposites. The degradation of methylene blue indicated that the incorporation of CuO in TiO2/CuO nanocomposite exhibited an appreciable higher photocatalytic activity, and more light energy could be utilized than pure TiO2. In addition, the degradation of methylene blue was also investigated using sonocatalysis and photosonocatalysis systems. The results showed that all experimental data followed the pseudo-first order model but the rate constant of the sonophotocatalysis is higher than the respective individual photocatalysis and sonocatalysis process. Furthermore, the photocatalytic, sonocatalytic and photosonocatalytic activities will be related to their structural and optical properties. The mechanism of catalytic activities will be discussed.

Abstrak :
Limbah zat warna merupakan salah satu kontributor terbesar dalam terjadinya polusi air. Degradasi limbah zat warna menggunakan suatu fotokatalis perlu dilakukan untuk menangani permasalahan limbah tersebut. CuBi2O4 dan CuO merupakan suatu semikonduktor tipe-p berbasis oksida logam yang memiliki celah pita sempit, menunjukkan respons yang sangat baik terhadap cahaya tampak, dan dapat digunakan sebagai fotokatalis. Akan tetapi, kedua  material tersebut menunjukkan aktivitas fotokatalitik yang buruk akibat laju rekombinasi pasangan elektron dan hole yang cepat, sehingga sintesis material heterojunction dilakukan untuk mengatasi kekurangan ini. Komposit CuBi2O4/CuO disintesis dengan berbagai variasi rasio massa CuBi2O4:CuO (1:1, 1:2, dan 2:1) menggunakan metode grinding annealing. Lebih lanjut, CuBi2O4/CuO CuBi2O4, dan CuO yang dihasilkan kemudian dikarakterisasi menggunakan instrumen XRD, FTIR, UV-Vis DRS, dan TEM. CuBi2O4 dan CuO menunjukkan celah pita sebesar 1,76 eV dan 1,55 eV. Perubahan nilai energi celah pita teramati ketika modifikasi dilakukan, yakni 1,73 eV, 1,70 eV, dan 1,59 eV. Pengujian aktivitas fotokatalitik terhadap metilen biru di bawah cahaya tampak selama 180 menit menunjukkan bahwa sintesis CuBi2O4/CuO efisien dalam meningkatkan aktivitas fotokatalitiknya dengan persentase degradasi sebesar 81,1%. Sedangkan CuO dan CuBi2O4 masing-masing menunjukkan persentase degradasi sebesar 73,3% dan 64,2%. ......Dye waste is one of the biggest contributors to water pollution. Degradation of dye waste using a photocatalyst needs to be done to deal with this waste problem. CuBi2O4 and CuO are metal oxide-based p-type semiconductors that have a narrow band gap, responsive to visible light, and can be used as photocatalysts material. Synthesis of CuBi2O4 and CuO using solvothermal and hydrothermal methods was successfully carried out which was confirmed by XRD, FTIR, TEM, and UV-Vis DRS. CuBi2O4 and CuO show bandgap energy 1.76 eV and 1.55 eV, respectively. However, both materials exhibit poor photocatalytic performance due to the fast recombination rate of electron-hole pairs, so that the synthesis of heterojunction materials was carried out to overcome this deficiency. CuBi2O4/CuO composite was synthesis by grinding annealing method using various CuBi2O4:CuO mass ratios (1:1, 1:2, and 2:1). Furthermore, CuBi2O4/CuO composite were characterized using XRD, FTIR, UV-Vis DRS, and TEM. Changes in the value of the band gap energy observed when modifications were made to 1.73 eV, 1.70 eV and 1.59 eV. The heterojunction CuBi2O4/CuO showed an enhanced photocatalytic performance with 81,1% removal of methylene blue within 180 min of visible light irradiation, compared to the results obtained with the pristine materials. While CuO and CuBi2O4 only showed 73,3% and 64,2% removal of methylene blue within 180 min of visible light irradiation.

Abstrak :
CuO/TS-1 catalysts have been prepared and tested in the benzene hydroxylation. TS-1 was synthesized by hydrothermal method, while CuO/TS-1 was prepared by impregnation method using Cu(NO)2. 3H2O as precursor. Catalysts were characterized by using X-ray diffraction (XRD), infrared spectroscopy (IR), and N2 adsorption-desorption techniques. The catalytic activity was tested in the hydroxylation reaction of benzene. The products were analyzed using gas chromatography. Catalyst characterization by XRD and IR techniques have showed that the catalyst structure was a MFI type of zeolite. XRD pattern have showed the orthorombic structure and indicated the presence of CuO aggregation. The results of the pyridine adsorption have found that the acidity of TS-1 and CuO/TS-1 were a Lewis acid and it?s increased with an increasing amount of CuO loading. The results of nitrogen adsorption analysis have showed decreasing of surface areas of catalyst with increasing amount of CuO loading. The optimum conditions of benzene hydroxylation was observed by 1%CuO/TS-1 catalyst at 70 °C, reaction time 2 h and acetic acid as the solvent yielded 27.6% of phenol with phenol selectivity was 75.5%

Abstrak :
Penelitian ini akan mensimulasikan temperatur transisi pada superkonduktor TBCCO. Secara umum, superkonduktor TBCCO dapat dituliskan sebagai dimana m adalah jumlah bidang TlO dan n adalah jumlah bidang CuO. Simulasi temperatur transisi superkonduktor TBCCO dapat dipelajari dengan menggunakan model ASYNNNI. Dalam model ASYNNNI, oksigen di tempatkan pada bidang CuO secara acak. Kandungan oksigen dan jumlah bidang CuO akan mempengaruhi besarnya temperatur transisi. Temperatur transisi tertinggi terjadi pada superkonduktor TBCCO yang mempunyai tiga bidang CuO dengan m1n2n1n2mOCuCaBaTl2m. Untuk 2m, temperatur transisi tidak dihasilkan dalam simulasi empat bidang CuO, karena bahan ini tidak bersifat superkonduktor.

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This research will simulate the transition temperature in supercondustors TBCCO. Generally, superconductors TBCCO can be written as where m is the number of TlO planes and n is the number of CuO planes. Simulation of transition temperature in superconductors TBCCO can be studied using ASYNNNI model. In ASYNNNI model, oxygen is placed in CuO planes randomly. The oxygen content and the number of CuO planes will affect on transition temperature level. The highest transition temperatur level is in three CuO planes superconductors TBCCO with m1n2n1n2mOCuCaBaTl2m. For 2m, transition temperature is not resulted in four CuO planes simulation because the material is not superconductor.

Abstrak :
Campuran Oksida Seng/Titanium Dioksida/Oksida Tembaga (ZnO/TiO2/CuO) dengan lima variasi rasio molar CuO disintesis dengan menggunakan metode sol-gel dan dikarakterisasi menggunakan Energy Dispersive X-Ray (EDX), X-Ray Diffraction (XRD), Field Emission Scanning Electron Microscope (FESEM) dan UV-visible Diffuse Reflectance Spectroscopy (UV- DRS). Aktivitas fotokatalitik diamati menggunakan larutan metilen biru (MB) di bawah pemaparan sinar Ultraviolet (UV) dan cahaya tampak dengan metal oksida ZnO/TiO2 sebagai pembanding. Hasil aktivitas fotokatalitik menunjukkan sampel dengan rasio molar CuO sebesar 0.5 dapat mendegradasi lebih baik di bawah paparan sinar UV dan cahaya tampak. Kondisi optimum aktivitas fotokatalitik didapatkan pada kondisi pH 13, dosis fotokatalis 0.2 g/L dan konsentrasi awal MB 20 mg/L baik di bawah paparan sinar UV maupun cahaya tampak. ......Zinc Oxide/Titanium Dioxide/Copper Oxide (ZnO/TiO2/CuO) metal oxide mixture with five various CuO molar ratio were synthesized using sol-gel method and were characterized by Energy Dispersive X-Ray (EDX), X-Ray Diffraction (XRD), Field Emission Scanning Electron Microscope (FESEM) and Ultraviolet- visible Diffuse Reflectance Spectroscopy (UV-DRS). Photocatalytic activities were observed by using methylene blue (MB) solution under Ultraviolet (UV) light and visible light irradiation using photocatalytic activity of ZnO/TiO2 metal oxide mixture as comparison. The result shows sample with 0.5 ratio molar of CuO have higher degradation capability on both UV light and visible light irradiation. Photocatalytic activity optimum condition were obtained at pH 13, 0.2 g/L of photocatalyst and 20 mg/L of MB initial concentration.