(Luận văn) the use of magnetic nanocomposites in fenton reaction for catalytic degradation of methylene blue

THAI NGUYEN UNIVERSITY UNIVERSITY OF AGRICULTURE AND FORESTRY lu an va n KHUONG NAM THAI p ie gh tn to TOPIC TITLE: THE USE OF MAGNETIC NANOCOMPOSITES IN FENTON REACTION FOR CATALYTIC DEGRADATION OF METHYLENE BLUE d oa nl w oi lm ul nf va an lu BACHELOR THESIS z at nh z Study mode: Full-time Major: Environmental Science and Management Faculty: International Training and Development Center Batch: 2010-2015 m co l gm @ an Lu Thai Nguyen, 15/01/2015 n va ac th i si DOCUMENTATION PAGE WITH ABSTRACT Thai Nguyen University of Agriculture and Forestry Degree program Bachelor of Environmental Science and Management Student name Khuong Nam Thai Student ID DTN1053110174 Thesis title The use of magnetic nanocomposite in Fenton reaction for lu an catalytic va n degradation of methylene blue to Asoc Prof Huang Yu-Fen1 & Dr Do Thi Ngoc Oanh2 gh tn Supervisor (s) Department of Biomedical Engineering and Environmental p ie Internship place d oa nl w Science, National Tsing Hua University, Taiwan ul nf va an lu Abstract oi lm Oxidation by Fenton-like reactions is proven and economically feasible z at nh process for destruction of a variety of hazardous pollutants in wastewater MNPs were synthesis via a thermal decomposition method and Au@FexOy via z @ electrooxidation procedure The synthesis of MNPs and Au@FexOy was gm m co l characterized by several techniques, Ultraviolet–visible spectroscopy (UV-Vis), and Transmission Electron Microscopy (TEM) The concentrations of dye degradation Department of Biomedical Engineering & Environmental Science, National Tsing Hua University, Taiwan Faculty of Agronomy, Thai Nguyen University of Agriculture and Forestry n va an Lu ac th ii si were determined spectrophotometrically using Plate Readers at 665 nm, the absorption maxima of the dye Moreover, in order to apply using magnetic nanocomposties in Fenton reaction for degradation of methylene blue, concentration of Iron ion and hydrogene peroxide must be optimized The magnetic nanocomposites showed good catalytic performance for MB organic dye oxidation by H2O2 after hours of reaction The reaction was able to lu an proceed at pH neutral in room temperature Finally, some future trends and n va prospective in this research areas are also discussed efficiency, spectrophotometrically, methylene blue, H2O2 tn Fenton reaction, magnetic nanocomposites , conversion gh to Keywords p ie Number of pages 44 nl w 15th January 2015 d oa Date of submission oi lm ul nf va an lu z at nh z m co l gm @ an Lu n va ac th iii si ACKNOWLEDGEMENT I would like firstly to thank Dr Do Thi Ngoc Oanh From the beginning, she had confidence in my abilities to not only complete a degree but to complete it with excellence I wish to thank the members of YF lab, Department of Biomedical Engineering lu and Environmental Science, National Tsing Hua University, Taiwan for their an n va support, patience and good humor Their gentle but firm direction has been most tn to appreciated Asoc Prof Yu-Fen Huang Supervisor’s interest in sense of competence p ie gh was the impetus for my project w Mr Andy PhD student’s, an extremely exemplary and responsible group oa nl leader, was particularly helpful in guiding me toward a qualitative methodology and d inspiring me in whole period of internship an lu nf va I would like to give a big acknowledgment to Advantaged Education Program oi lm ul that giving me a great chance in taking this thesis research Especially Dr Duong Van Thao Headteacher’s who is enthusiasm supports me in whole time study z at nh Finally I would like to send to my parents and the whole family gratitude and z affection m co l gm @ an Lu n va ac th iv si TABLE OF CONTENTS LIST OF FIGURES LIST OF TABLES PART I INTRODUCTION 1.1 Research rationale 1.2 Research’s objective lu PART II LITERATURE REVIEW an n va 2.1 Nanotechnologies and nanomaterials tn to 2.2 Synthesis of nanonaterials p ie gh 2.2.1 General principles w 2.2.2 Magnetic nanoparticles oa nl 2.2.3 Synthesis of gold@iron oxide nanoparticles 10 d 2.2 Overview of research and application of nanomaterial and nanocomposite 14 an lu nf va 2.2.1 Electronic technology and information technology 14 oi lm ul 2.2.2 Environmental treatment material 15 2.3 Fenton reaction and its application for degradation of methylene blue 16 z at nh 2.3.1 Fenton reaction 16 z 2.3.2 Fenton reaction for degradation of methylene blue 17 @ l gm 2.4 The use of magnetic nanocomposites in Fenton reaction for catalytic m co degradation of methylene blue 19 an Lu 2.5 The equipment used to determine the properties of gold nanoparticles and methylene blue degradation 19 n va ac th v si 2.5.1 Ultraviolet–visible spectroscopy (UV-Vis) 19 2.5.2 Transmission Electron Microscopy (TEM) 20 PART III METHODS 23 3.1 Materials 23 3.1.1 Chemicals 23 3.1.2 Equipment 24 lu an 3.2 Methods 24 n va 3.2.1 Determine the optimum concentration of Fe2+ 24 gh tn to 3.2.2 Determine the optimum concentration of H2O2 28 p ie 3.2.3 Effect of pH value on conversion efficiency of MB 29 nl w 3.3.4 Degradation of MB by Iron (II), Iron (III) 30 d oa 3.3.5 The use of MNC, Au@FexOy in degradation of MB 31 an lu PART IV RESULTS 33 nf va 4.1 Determination the optimum the concentration of Iron (II) for degradation of oi lm ul MB 33 4.2 Determination the optimum concentration of H2O2 for degradation of MB 34 z at nh 4.3 Effect of pH value on degradation of MB 35 z gm @ 4.4 Degradation of MB by Iron (II), Iron (III) 36 4.5 The use of MNC, Au@FexOy in degradation of dye 37 l m co PART V DISCUSSION AND CONCLUSION 44 an Lu 5.1 Discussion 44 n va 5.2 Conclusion 44 ac th vi si REFERENCES 45 lu an n va p ie gh tn to d oa nl w oi lm ul nf va an lu z at nh z m co l gm @ an Lu n va ac th vii si LIST OF FIGURES Figure 1.3 TEM images of Fe3O4 NPs in different scale bar: (a) 50 nm; (b) 100 nm 10 Figure 1.4 UV–Vis spectra of AuNP electrooxidation with different time using citrate buffer 12 Figure 1.5 TEM image of a) AuNP( core ± Shell: 48 ± nm); b) Au@Fe xOy at lu 550 electrooxidation-citrate buffer (core ± Shell: 12 ± nm); c) an n va Au@FexOy at 360 electrooxidation-citrate buffer (core ± Shell: 51 tn to ± 12 nm) and d) Au@FexOy at twice electrooxidation (core ± Shell: ie gh 44 ± 21 nm) 13 p Figure 1.6 TEM images of a) Au@FexOy and b) Au@FexOy through an annealing oa nl w process in mM citrate buffer (pH 6.8) with 30 sonication d Annealing condition: 350℃, 6h in N2 13 lu va an Figure 1.1 Ultraviolet–visible spectroscopy (UV-Vis) 20 ll u nf Figure 1.2 Schematic diagram of a TEM Generally, TEM is divided into two oi m main parts: illumination and imaging 21 z at nh Figure 1.9 Degradation MB by different Fe2+ concentration in 60 minutes, pH = z 2-3.5 33 @ l gm Figure 2.1 Degradation MB by different [H2O2] concentration in 60 minutes, pH = 2-3.5 34 m co Figure 2.2 Effect of pH on degradation of MB 35 an Lu n va ac th si Figure 2.3 Degradation of methylene blue by Fe (II); Fe (II) + Fe (III) and Fe (III) at pH 2.5-3.5 37 Figure 2.4 Degradation of methylene blue by MNC, H2O2 4x and pH = 38 Figure 2.5 Degradation of methylene blue by MNC, H2O2 8.82×10−1 M (200x), pH = with spike at hours 39 Figure 2.6 Degradation of MB by MNC, Au@FexOy after annealing, Au@FexOy before annealing at pH = 7, [H2O2] = 2000x 40 Figure 2.7 Degradation of MB by a) H2O2 + H2O, b) Fe(II), c) Fe(III), d) lu an Fe(II)+Fe(III), e) Au@FexOy after annealing, f) Au@FexOy before va n annealing and g) MNC (pH = 7) 41 tn to Figure 2.8 Photos of A) degradation of MB by MNC at the beginning, a)-b) at the p ie gh end of reaction and B) degradation of MB by Fe (II) at the end of nl w reaction with concentration of 200 times dilute fold of H2O2 (pH = 7) d oa after 12 hours 42 ll u nf va an lu oi m z at nh z m co l gm @ an Lu n va ac th si LIST OF TABLES Table 1.1 Chemicals used in the experiment 23 Table 1.2 Preparation of Methylene blue stock solution 24 Table 1.3 Preparation stock solution of Fe2+ 25 Table 1.4 Preparation stock solution of H2O2 26 lu an n va p ie gh tn to d oa nl w ll u nf va an lu oi m z at nh z m co l gm @ an Lu n va ac th si PART IV RESULTS 4.1 Determination the optimum the concentration of Iron (II) for degradation of MB To determine the optimum Iron (II) concentration we used different Iron (II) concentrations as following: treatment 1(Fe 0x, M), treatment (3.58×10−5 M), treatment (1.43×10−4 M), and treatment (2.86×10−4 M) lu an Those concentration have the same concentration base with MB, n va 3.13×10−5 M and H2O2, 1.76×10−3 M, respectively The pH was adjusted from 2- to p ie gh tn 3.5 by adding 10 µL H2SO4 0.97% Fe 0x w 40 nl Fe 1x oa Fe 4x Fe 8x 30 an lu Conversion efficiency (%) d 20 u nf va 10 ll m oi z at nh 30 60 Time (min) z gm @ Figure 1.9 Degradation MB by different Fe2+ concentration in 60 minutes, pH = 2-3.5 m co l The graph showed the degradation of MB by different Fe2+ concentration in 60 minutes With the increase concentration of Fe2+, the conversion efficiency an Lu increased It also increased with a rise of time, from to 60 minutes Within 60 n va minutes, conversion efficiency of MB was highest at 60 minutes and Fe 8x was ac th 33 si highest conversion efficiency with 41% at 60 minutes and Fe 0x was lowest at 1.4% 4.2 Determination the optimum concentration of H2O2 for degradation of MB To determine the optimum H2O2 concentration we used different H2O2 concentrations as following: treatment (H2O2 0.5x, M), treatment (H2O2 1x, 4.41×10−4 M), treatment (H2O2 2x, 8.82×10−4 M), treatment (H2O2 4x, 1.76×10−3 M), and treatment (H2O2 8x, 3.52×10−3 M) lu an n va Those concentration have the same base concentration of MB, 3.13×10 −5 gh tn to M and Fe2+ 2.86×10−4 M, respectively The pH was adjusted from 2-3.5 by adding 10 µL H2SO4 0.97% p ie 40 oa nl w 45 35 d H2O2 0x va 20 H2O2 0.5x u nf 15 H2O2 1x H2O2 2x ll 10 H2O2 4x m oi Conversion Efficiency (%) an 25 lu 30 -5 10 20 z at nh 30 40 50 60 TIme (min) z gm @ Figure 2.1 Degradation MB by different [H2O2] concentration in 60 minutes, pH = 2- m co l 3.5 The graph presented the degradation of MB by different H2O2 concentration an Lu within 60 minutes With the increase concentration of H2O2, the conversion n va ac th 34 si efficiency increased It also increased with a rise of time, from to 60 minutes Within 60 minutes, conversion efficiency of MB was highest at 60 minutes and H2O2 4x was highest conversion efficiency with 41% at 60 minutes and H2O2 0.5x was lowest at 1.5% 4.3 Effect of pH value on degradation of MB To determine the effect of pH value on degradation of MB, experiments were conducted with treatments by base of [Fe2+], Fe 8x and [H2O2], H2O2 4x as following: treatment (pH 2.5-3.5), treatment (pH 4-5.5), treatment (pH 7- lu an 7.5) n va gh tn to 45 d oa nl w Conversion efficiency (%) p ie 30 pH 2.5-3.5 lu pH 4.5-5 15 30 ll u nf va an pH 7-7.5 60 oi m Time (min) z at nh Figure 2.2 Effect of pH on degradation of MB z The graph presented the degradation of MB by different pH value within 60 @ m co increased l gm minutes Surprisingly, with the increase pH value, the conversion efficiency an Lu But the conversion efficiency still increased with a rise time, from to 60 minutes Within 60 minutes, conversion efficiency of MB was highest at 60 n va ac th 35 si minutes The treatment 1, was adjusted pH 2-3.5, was highest conversion efficiency with 41% at 60 minutes Treatment 3, was adjusted pH 7, was lowest the conversion efficiency at 33 % 4.4 Degradation of MB by Iron (II), Iron (III) Both Fe3O4 magnetic nanoclusters and Au@FexOy nanocomposites have good catalytic potential on the degradation of methylene blue (Andre, 2014) In theory, the ratio between Fe (II) and Fe (III) reactants of Fe3O4 magnetic NPs was 0.5 As a result, Fe (II); Fe (III); Fe (II) + Fe (III) solution was considered to lu an be our positive control which compared with our magnetic nanoclusters and n va Au@FexOy gh tn to According to Figure 2.3, the decomposition of H2O2 reaction was rapid at p ie the beginning when in the Fe (II) solution whereas decomposition of H2O2 was nl w slightly slower Interestingly, the changed profile of the mixed Fe (II) and Fe d oa (III) solution was similar approach to Fe (II) So, according to above observation, lu va an we assume that while the decomposition of MB start with Fe (III), other reaction u nf may be involved during the decomposition reaction, which was shown below: ll Fe3+ + HO2• = Fe2+ + O2 + H+ oi m (4) (5) 2HO2• = H2O2 + O2 (6) z at nh Fe2+ + HO2• + H+ = Fe3+ + H2O2 z gm @ Although, the reaction was prior to Fe (II) for the degradation, still all the m co l three groups achieve to 90 % The reaction was almost complete an Lu n va ac th 36 si 100 Conversion efficiency (%) 80 60 Fe(II) 40 Fe(II) + Fe(III) Fe(III) 20 0 50 100 150 200 250 300 Time (min) lu an Figure 2.3 Degradation of methylene blue by Fe (II); Fe (II) + Fe (III) and Fe (III) at pH va 2.5-3.5 n to gh tn 4.5 The use of MNC, Au@FexOy in degradation of dye p ie 1) According to the optimum concentration of iron (II) and H2O2 as nl w described in those experiments above, we apply to using magnetic oa nanocomposites in Fenton reaction for degradation of MB In the treatment, we d used MNC with 2.86×10−4 M and H2O2, 1.76×10−3 M (4x), pH adjusted by an lu ll Figure 2.4 u nf va adding 5µL NaOH in the solution The conversion efficiency was presented in oi m z at nh z m co l gm @ an Lu n va ac th 37 si 100 H2O2 4x Conversion efficiency (%) 80 60 40 20 0 100 200 300 400 500 Time (min) lu an Figure 2.4 Degradation of methylene blue by MNC, H2O2 4x and pH = va n From figure 2.4, degradation of MB by MNC with H2O2 4x, conversion tn to efficiency is very low It became constant after 30 minutes The max concersion gh p ie efficiency is 10% at 420 So the concentration of H2O2 here was not nl w optimum for degradation of MB by magnetic nanoparticles d oa 2) To verify the conversion ability of magnetic nanocomposites on lu va an degradation of dye, we conducted experiment with concentration of H2O2 at 200 u nf times dilute fold for hours incubation Then, we further spike 20 µL H2O2 8.82 ll M in solutions to realize the degradation procedure oi m z at nh z m co l gm @ an Lu n va ac th 38 si 40 H2O2 200x Conversion efficiency (%) 30 Spike 20 10 0 150 300 450 600 750 Time (min) lu an Figure 2.5 Degradation of methylene blue by MNC, H2O2 8.82×10−1 M (200x), pH = va with spike at hours n gh tn to From the figure 2.5, when increase H2O2 concentration up to 200x, the p ie conversion efficiency is still low and almost no reaction at 300 Surprisingly, nl w after adding 20µL H2O2 8.82 M, conversion efficiency rapid increases tend to a d oa 39% at 720 minutes This is a base for determination of H2O2 on MB an lu degradation, we conduct experiment following u nf va 3) MNC and Au@FexOy was further investigated for MB degradation ll afterwards The experiments were conducted with MNC, Au@FexOy before m oi annealing and Au@FexOy after annealing at the same concentration 2.86×10−4 M z at nh (Figure 2.6) The concentrations of H2O2 were kept at 8.82 M (2000 times diluted z m co l gm @ fold) an Lu n va ac th 39 si 100 MNC Au@FexOy After ann Conversion efficiency (%) 80 Au@FexOy Before ann, 60 40 20 0 50 100 150 200 250 300 Time (min) lu an Figure 2.6 Degradation of MB by MNC, Au@FexOy after annealing, Au@FexOy before va annealing at pH = 7, [H2O2] = 2000x n gh tn to In figure 2.6, it showed that magnetic composite has well done reaction in p ie the presence of H2O2 in Fenton reaction Maximum conversion efficiency of nl w Au@FexOy after annealing, Au@FexOy before annealing and MNC are 80%, d oa 23% and 71%, respectively We found that the behavior between Au@FexOy an lu before and after through annealing process performed significantly different ll % in magnetic particles u nf va behaviors in degradation Surprisingly, the reaction was achieved almost 70-80 m oi 4) To compare and assement the effectiveness between Iron ion and z at nh magnetic nanocomposites, experiments were conducted with treatments: m co an Lu n va - Treatment 5: MNC, 2.86×10−4 M l - Treatment 4: Fe 2++Fe3+ gm - Treatment 3: Fe3+ @ - Treatment 2: Fe2+ z - Treatment 1: H2O2 + H2O ac th 40 si - Treatment 6: Au@FexOy after annealing, 2.86×10−4 M - Treatment 7: Au@FexOy before anealing, 2.86×10−4 M 100 a) b) 80 c) lu Conversion efficiency (%) d) e) f) 60 g) an 40 n va 20 tn to gh 50 100 150 200 250 300 p ie Time (min) nl w Figure 2.7 Degradation of MB by a) H2O2 + H2O, b) Fe(II), c) Fe(III), d) Fe(II)+Fe(III), d oa e) Au@FexOy after annealing, f) Au@FexOy before annealing and g) MNC (pH = 7) an lu According to Figure 2.7, degradation of MB by Iron ion (II and III) group whereas groups from Au@FexOy, MNC was much slower when oi m reaction began ll minnutes u nf va were rapid at the beginning of reaction with 90% conversion efficiency within 60 z at nh We found the precipitants from the magnetic particles in the bottom of z gm @ plastic tubes after the experiments completed In detail, as we can see from Figure 2.8 (B), there were yellow precipitants on degradation of MB by Fe (II) l m co This is evidence that Fe (II) is converted in to Fe (III) at the end of reaction On an Lu degradation of MB by magnetic nanocomposites, there are also precipitants at the n va end of reaction as present on Figure 2.8 (A) However, these are magnetic ac th 41 si nanoparticles after reaction and they still have magnetic field This is very important indicating advantages of using magnetic composites in Fenton’s reaction We can reuse or recycle them not only once use that presented in many studies with the benefit in reuse of magnetic nanoparticles (Han et al., 2014) lu an n va p ie gh tn to w oa nl Figure 2.8 Photos of A) degradation of MB by MNC at the beginning, a)-b) at the end d of reaction and B) degradation of MB by Fe (II) at the end of reaction with an lu concentration of 200 times dilute fold of H2O2 (pH = 7) after 12 hours u nf va In addition, even all the experiment for degradation of MB by magnetic ll nanoparticles were controlled with pH neutral (pH = 7) which was more suitable oi m in real situation, the conversion efficiency was still remain certain extent z at nh compare to Iron (II)/Iron (III) Although the best condition for fenton reaction z gm @ was conducted in pH 2.5-3.5 m co l On the other hand, with core-shell nanostructure, probably because there was only an amount of Iron ion on surface of magnetic nanocomposites reacted an Lu with H2O2 in Fenton reaction; however, there was still iron ion inside non-react n va ac th 42 si In fact, when using Iron (II) or Iron (III) in Fenton’s reaction occurred in real wastewater environment, totally Iron ion will take part in the reaction However, Iron ions not only reacting with H2O2 same as in theory, it also reacts with ions or organic compounds in wastewater, this will affect to the conversion efficiency of degradation of dye By contrast, magnetic nanocomposites, will prevent nanoparticles and block organic compunds in wastewater react with iron ion This indicated the conversion efficiency of MNC and Au@FexOy lower than Iron (II)/Iron (III) but more realistic in the real cases lu an n va p ie gh tn to d oa nl w ll u nf va an lu oi m z at nh z m co l gm @ an Lu n va ac th 43 si PART V DISCUSSION AND CONCLUSION 5.1 Discussion For degradation of methylene blue by Iron ions, the optimum concentrations of Iron ion, hydrogen peroxide were Fe 8x (2.86×10−4 M ) and H2O2 4x (1.76×10−3 M) was an optimum Fe2+ concentration for the most effective degradation of 3.13 × 10−5 M MB solution, the optimum pH value range from 24 For degradation of MB by magnetic nanocomposites, the optimum H2O2 lu an concentration is 2000x (8.82×10−1 M) After hours, magnetic nanocomposites n va performed good in Fenton reaction for degradation of methylene blue with tn to ie gh conversion efficiency of MNC at 71%, Au@FexOy after annealing at 80% and p Au@FexOy before annealing at 23% oa nl w 5.2 Conclusion Gold@iron oxide nanoparticles 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