Applications of graphene based nanomaterials sio2cgraphene composites to absorb heavy metal in water

(P laceholder1) THAI NGUYEN UNIVERSITY UNIVERSITY OF AGRICULTURE AND FORESTRY VU XUAN TRUONG APPLICATIONS OF GRAPHENE-BASED NANOMATERIALS (SIO2@C@GRAPHENE COMPOSITES) TO ABSORB HEAVY METAL IN WATER BACHELOR THESIS Study Mode : Full-time Major : Environmental Science and Management Faculty : International Training and Development Center Batch : 2011-2015 Thai Nguyen, 07/27/2016 DOCUMENTATION PAGE WITH ABSTRACT Thai Nguyen University of Agriculture and Forestry Degree Program Bachelor of environmental Science and Management Student name Vu Xuan Truong Student ID DTN1054120172 Applications of graphene-based nanomaterials Thesis Title Supervisors ( SiO2@c@graphene composites) to absorb heavy metal in water 1, Prof Ruey-an Doong, National Tsing -Hua University, Taiwan 2, Dr Ho Ngoc Son, Thai Nguyen University of Agriculture and Forestry, Vietnam Abstract: The purposes of this study are synthesis graphene oxide (GO), SiO2 @C@Graphene composites and check characterization of synthesized GO and SiO2@C@GO The crystallite size and phase characteristic of the product were determined by using the XRD pattern Compositional analysis of the as-prepared samples was performed by Fourier transform infrared spectroscopy (FT-IR) The morphologies and size of the samples were obtained by field emission scanning electron microscopy (FESEM) and Transmission electron microscopy (TEM) Analyze the Adsorption properties of samples by using Atomic absorption spectroscopy (AAS) Conclusion, SiO2@C@graphene composites prepared here could be a promising candidate sorbent material for removing heavy metal ions from aqueous The i outstanding physicochemical properties of the SiO2@C@graphene composites materials play a very important role in environmental pollution management in the future of human life Keywords GO, SiO2@C@Graphene adsorption Number of papers 37 pages Date of submission September 20th, 2016 composites, hydrothermal ii ACKNOWLEDGEMENT Luckily, I have a valuable internship chance to learning and professional improvement in Department of Biomedical Engineering and Environmental Sciences in National Tsing Hua University (NTHU), Taiwan First of all, I want to thank my supervisors Prof Ruey-An Doong and Dr Ho Ngoc Son, those who took the time out to listen, guide, bolster and support me on the right way and allowing me to complete my study to have fruitful results Particularly, their extremely valuable guidance are not a little commitment in orienting my professions and future Secondly, I am grateful to Nguyen Thanh Binh Ph.D and Miss Khuat Thi Thanh Huyen about their help dedicated during my studies and research in this laboratory They was hearted guidance, given the comments and the orientation in my experiment steps as well as the process of writing my report I would like to thank my friends in the laboratory for their guidance to use a variety of important machinery serving my experiments Last but not least, thanks to my parents and good friends who always encourage me and offer support and love Sincerely, Vu Xuan Truong iii TABLE OF CONTENTS TABLE OF CONTENTS IV LIST OF FIGURES LIST OF ABBREVATIONS PART I INTRODUCTION 1.1 Research rationale 1.2 Research objective 1.5 Definitions PART II LITERATURE REVIEW 2.1 Overview of heavy metals 2.1.1 Definitions and sources of heavy metals 2.1.2 Characteristics of heavy metals 2.2 The current situation of water heavy metal contamination in the world 2.3 Characteristics and hazards of some heavy metal contamination 10 2.3.1 Arsenic (As) 10 2.3.2 Lead (Pb) 12 2.3.3 Copper (Cu) 14 2.4 Some methods for treatment heavy metals in aqueous solutions 16 2.4.1 Phytoremediation Technology 17 2.4.3 Overview of Graphene Oxide 18 2.4.4 Overview of mesoporous composites and SiO2@C@Graphene composite20 PART III METHODS 21 3.1 Material 21 3.1.1 Chemicals 21 iv 3.1.2 Instruments 21 3.2 Methods 22 3.2.1 Synthesis of GO 22 3.2.2 Synthesis SiO2@C@GO 24 3.2.4 Characterization 26 PART IV RESULTS 27 4.1 Characterization of GO and SiO2@C@graphene composites 27 4.1.1 XRD 27 4.1.2 FTIR 28 4.1.3 FE-SEM and TEM 29 4.1.4 Zeta potential 30 4.1.5 AAS 31 PART V DISCUSSION AND CONCLUSION 33 5.1 Discussion 33 5.2 Conclusion 34 REFERENCES 35 v LIST OF FIGURES Figure 1: Various processes involved in the phytoremediation of heavy metals (Ruchita Dixit, Wasiullah, Deepti Malaviya, Kuppusamy Pandiyan, Udai B Singh, Asha Sahu, Renu Shukla, Bhanu P Singh, Jai P Rai, Pawan Kumar Sharma, Harshad Lade, Diby Paul, 2015) 17 Figure The six proposed structure models of graphene oxide(Wei Gao, 2012) 19 Figure Synthesis of mesoporous composites from waste panel glass for selective adsorption of heavy metal ions (Yazawa et al.,1984) 20 Figure Some instruments used for this study: a) Centrifuge machine, b) Ultrasonic treatment, c) pH adjustment, d) Atomic adsorption spectroscopy, e) Rotary vacuum evaporator, f) Vortex, g) Drying oven 22 Figure Preparation of go by Hummers method 23 Figure Photograph: a) GO solution b) GO nanoparticles after drying 24 Figure Schematic illustration of the synthesis route for the sio2@c@graphene composites( Yurong Ren, Hengma Wei, Xiaobing Huang, Jianning Ding, 2014) 25 Figure SiO2@c@GO nanoparticles after drying 25 Figure XRD patterns of the as-synthesized (a) GO, (b) SiO2 nanoparticles, (c) SiO2@C composites, and (d) SiO2@C@graphene composites 27 Figure 10 FT-IR spectra of SiO2 nanoparticles, carbon precursor coated sio2 nanoparticles, GO, and SiO2@c@graphene composites 28 Figure 11 FE-SEM images of GO and SiO2@C@graphene composites 29 Figure 12 TEM images of sio2 and SiO2@C@GO 30 Figure 13 Zeta potential and ph graph of SiO2@c@go 31 Figure 14 The adsorption cu (ii) (10mg/l) by SiO2@c@go at pH=5 in aqueous solution at 25OC 31 LIST OF ABBREVATIONS Abbreviations Full text content XRD X-ray Diffraction TEM Transmission electron microscopy FE-SEM AAS GO Field emission-scanning electron microscopy Atomic adsorption spectroscopy Graphene oxide FTIR Fourier transform infrared spectroscopy RVE Rotary Vacuum Evaporate PART I INTRODUCTION 1.1 Research rationale Water is a precious resource that nature bestowed on man, no water, no life and no economic activity can exist Water is the beginning and the necessities of life; is a key factor of production; a key factor in secured environmental However, water resources are increasingly scarce, volume and water quality declining, droughts, floods fiercer in both the scale and the extent and timing of the demand for water increasing and there was a reason for causing the water crisis in many parts of the world During the industrialization process, underground water sources are facing some problems as widespread salinization, microbial contamination and heavy metals pollution seriously, because underground water drilling without planning and without plan water protection Providing clean water is the prime requirement of the human being for their better health Since the fast growing sector of industries, expansion of the population, urbanization have largely contributed to the severe contamination of water, air and soil Chemical and fertilizer use in domestic and agricultural activities leads to the lifetime threatening diseases Intense use of heavy metals in industries for dyeing, paint etc Is becoming one of the most serious environmental problems globally Its presence in low concentration of heavy metals in various water resources could be harmful to human health The treatment of heavy metals is so important due to their persistence in the environment And among several physical, chemical and biological treatment techniques, the adsorption is one of the simplest, fastest and most efficient processes or the removal of heavy metals More recently, Graphene oxide (GO) has attracted tremendous interest in the world Graphene is a two-dimensional carbon nanomaterial with single layer of sp2 hybridized carbon atoms arranged in six membered rings Graphene has strong mechanical, thermal, and electrical properties with a theoretical value of specific surface area of 2630 m2/g GO is a functionalized graphene with varying oxygen containing groups Several views have been reported on the applications of GO in different areas such as physics, chemistry, biology, and material science In particular, graphene based materials are used as adsorbents for pollutant removal since graphene oxide possesses several functional groups and has strong acidity, exhibiting high adsorption for basic compounds and cations Graphene also has a hydrophobic surface and presents high adsorption to chemicals due to strong π–π interaction (Gao, 2012) Considering all aspects and issues mentioned above, I propose research:" Applications of graphene-based nanomaterials (SiO2@C@graphene composites) to absorb heavy metal in water " 1.2 Research objective - Synthesis graphene oxide (GO), SiO2@C, SiO2 @C@Graphene composites for the removal of toxic heavy metals from aqueous solution - Checking materials characterization by using powder X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), field emission scanning electron microscopy (FESEM) and transmission electron microscope (TEM); - Assessing the efficiency of SiO2 @C@Graphene composites to absorb heavy metals in water 1.5 Definitions GO: Graphene oxide (GO) is a two-dimensional material derived from graphite by introducing covalent C=O bonds 1The bulk form of GO, conventionally named In Hummers method, the reaction can be completed within a few hours it has been paid the most intensive attention because of its high efficiency and satisfying reaction safely (Ji Chen, Bowen Yao, Chun Li & Gaoquan Shi, 2013) Figure illustrated the preparation method of graphene oxide In brief, 225 ml H2SO4 and 25ml H3PO4 and 2g of natural graphite is added in a round bottom and mixed, stirred together by a magnetic stirrer After that, add 5g KMnO4 batch by batch and then heat to appropriate temperature 35oC for 10 hours Later, the solution is added into 225ml DI water in ice bath to exchange H2SO4 in the sheet followed by 5ml H2O2 to reduce residual KMnO4 was added in a beaker and mixed it well at room temp The solution will change into deep brown to bright brown color, according to the oxidation degree Washing with 1M HCl 15ml, then pH=11 PO43-/ HPO42- buffer 3ml + DI water 15ml was done sequentially The procedure is repeated for two or three times until pH will reach neutral Finally, a solution was dried by using Rotary Vacuum Evaporate (RVE) with water-bath at 45~ 600C and thus graphene oxide sheets were obtained The produce was shown in figure Figure 5: Preparation of GO by hummer’s method 23 a) b) Figure 6: Photograph: a) GO solution b) GO nanoparticles after drying 3.2.2 Synthesis SiO2@C@GO SiO2 nanoparticles were coated with a glucose-derived carbon precursor by a simple hydrothermal method The processing can be defined as any heterogeneous reaction in the presence of aqueous solvents or mineralizers under high pressure and temperature conditions to dissolve and recrystallize (recover) materials that are relatively insoluble under ordinary conditions (Byrappa et al 2007) In figure 7, SiO2 ethanol suspension (7.5 mg/ml) and GO aqueous suspension (1 mg/ml) were dispersed by ultrasonic treatment, respectively Secondly, g of glucose was dissolved in 40 ml deionized water and mixed with SiO2 dispersion, then the resulting suspension was sealed in a 100-mL Teflon-lined autoclave and retained at the 180 OC for 10 h After that, the resultant was centrifuged and washed with water Thirdly, the collected product was added into 60 ml GO aqueous suspension and sonicated for h to yield a homogeneous suspension, and then sealed in a 100-mL Teflon-lined autoclave and retained at 180 oC for 12 h Finally, the product was centrifuged and washed with water and ethanol, then dried at 60oC for 24 24 h The produce was shown in figure For comparison, SiO2@C composites were prepared in the same way without the addition of GO (Yurong Ren, Hengma Wei, Xiaobing Huang, , Jianning Ding, 2014) Figure 7: Schematic illustration of the synthesis route for the S (2@C@graphene composites (Yurong Ren, Hengma Wei, Xiaobing Huang, Jianning Ding, 2014) Figure 8: SiO2@C@GO nanoparticles after drying 25 3.2.4 Characterization Characterization of synthesized GO and SiO2@C@GO were done by X-ray diffraction (XRD), Transmission electron microscopy (TEM) and Fourier transform infrared spectroscopy (FT-IR), field emission scanning electron microscopy (FESEM); The crystallite size and phase characteristic of the product were determined by using the XRD pattern Compositional analysis of the as-prepared samples was performed by Fourier transform infrared spectroscopy (FT-IR) The morphologies and size of the samples were obtained by field emission scanning electron microscopy (FESEM) and Transmission electron microscopy (TEM) 26 PART IV RESULTS 4.1 Characterization of GO and SiO2@C@graphene composites 4.1.1 X-ray Diffraction (XRD) The XRD patterns of GO, SiO2 nanoparticles, SiO2@C composites and SiO2@C@graphene composites are illustrated in Fig.9 (d) (c) (b) (a) Figure 9: XRD patterns of the as-synthesized (a) GO, (b) SiO2 nanoparticles, (c) SiO2@C composites, and (d) SiO2@C@graphene composites Figure (a) Shown the typical diffraction peak at 10°corresponds to the diffraction line of GO, Fig.9 (b) and Fig.9 (c) show similar patterns with amorphous SiO2 The XRD pattern of SiO2@C@graphene composites in Fig.9 (d) has no any peaks of GO or graphite, and has a little shift to SiO2@C composites and bare SiO2 nanoparticles, which could be caused by graphene and reveals that GO has been 27 reduced by the hydrothermal synthesis and the most graphene nanosheets were separated by SiO2@C particles 4.1.2 Fourier transform infrared spectroscopy (FTIR) For SiO2 nanoparticles in Fig 10, the peaks at 470 cm-1, 798 cm-1 and 1100 cm-1 are assigned to O-Si-O is bending vibration, Si-O-Si symmetric stretching vibration and Si-O-Si unsymmetric stretching vibrations, respectively Comparing to SiO2@carbon precursor, shows almost the same peaks at the same positions, except for a broad peak between 3700 and 3000 cm-1 corresponds to O-H stretching vibration of hydroxyl or carboxyl, and the weak hump at 960 cm-1 corresponds to Si–O stretching vibration of Si–OH Figure 10: FT-IR spectra of SiO2 nanoparticles, carbon precursor coated SiO2 nanoparticles, GO, and SiO2@C@graphene composites For GO, the peaks confirm the presence of the oxygen containing functional groups in the carbon frameworks The peaks at 1722, 1400, 1229 and 1068 cm-1, corresponding to C=O stretching of carbonyl groups, C-OH is stretching vibrations, C28 O vibrations of epoxy groups and C-O vibrations of alkoxy groups, respectively In addition, the wide band between 3700 and 3000 cm-1 corresponds to O-H stretching vibration in the FT-IR spectrum of SiO2@C/graphene composite is weaker than carbon precursor coated SiO2 and GO indicates that some O-H disappeared after the hydrothermal process This result also indicates that the oxygen-containing functional groups on the GO sheets and carbon precursor coated with SiO2 nanoparticles can react with each other during the hydrothermal process 4.1.3 Field emission-scanning electron microscopy (FE-SEM) and Transmission electron microscopy (TEM) The morphology of the as-arranged examples is described by field emissionscanning electron microscopy (FESEM) (Fig 11) and transmission electron microscopy (TEM) (Fig 12) From the TEM pictures of SiO2, the SiO2 shows a semicircular shape with distances across going 100 nm It likewise demonstrates that the SiO2 have agglomerated and poor scattering This outcome can translate the poor electrochemical execution of cathodes arranged by uncovered SiO2 nanoparticles, which will be delineated in Fig.11 Figure 11: FE-SEM images of GO and SiO2@C@graphene composites 29 From the SEM picture of SiO2@C@graphene composites, we could watch the insertion of SiO2@C nanoparticles between the interlayers of GO along the slant The TEM picture of SiO2@C@GO uncovers that the SiO2@C nanoparticles are wrapped by the graphene oxide film or installed in the GO system SiO2@C@GO SiO2@C@GO SiO2 Figure 12: TEM images of SiO2 and SiO2@C@GO 4.1.4 Zeta potential Zeta potential is a marker of scattering solidness The zeta capability of any scattering is affected by the surface chemistry The surface chemistry can be changed by any number of means incorporating an adjustment in the pH, salt fixation, surfactant focus, and other detailing choices It is as often as desirable to decide how pH influences the zeta capability of a scattering An isoelectric point estimation concentrates how pH impacts zeta potential and decide at which pH the zeta potential equivalents zero 30 Zeta potential (mV) -5 SiO2@C@GO -10 -15 -20 -25 -30 10 pH Figure 13: Zeta potential and pH graph of SiO2@C@GO The pH and zeta potential plot for SiO2@C@GO is shown in Figure 13 The isoelectric point (IEP) of SiO2@C@GO was determined to be 2.8 It can be seen that if the zeta potential is positive belong to pH 1-2.8 However, if the pH of the system has a pH between 2.8 and 10, the zeta potential is negative from to -28mV 4.1.5 Atomic adsorption spectroscopy (AAS) 1.0 0.8 C/Co 0.6 0.4 0.2 0.0 20 40 60 80 100 120 Time (min) Figure 13: The adsorption Cu (II) (10mg/L) by SiO2@C@GO at pH=5 in aqueous solution at 25oC 31 The adsorption Cu (II) (10mg/L) by SiO2@C@GO at pH=5 in aqueous solution at 25oC was analyzed by using Atomic adsorption spectroscopy (AAS) The outcomes exhibited in figure 14 above In the fixation 10ppm, amid an hour, to begin with, the partition effectiveness Cu (II) particle out of aqueous solution expanded significantly and came to 80% An hour later, 100% Cu (II) particle is consumed by SiO2@C@GO nanocomposite in aqueous solution It is unmistakable that the incorporated SiO2@C@GO composite with high surface areas, and in addition surface usefulness, is useful for the adsorption metal in aqueous solution 32 PART V DISCUSSION AND CONCLUSION 5.1 Discussion In general, the study has developed a graphene-based nanocomposite for the removal of toxic heavy metals from aqueous solution, specifically, use SiO2@C@graphene composites for the adsorption Cu (II) ion in aqueous solution GO has a unique morphology, chemical structure, and electronic properties In this study, we have synthesized SiO2@C and SiO2@C@GO by hydrothermal method, graphene oxide by Hummers method, and their adsorption capacity was evaluated Characterization of synthesized GO and SiO2@C@GO were done by X-ray diffraction (XRD), Transmission electron microscopy (TEM) and Fourier transform infrared spectroscopy (FT-IR), field emission scanning electron microscopy (FESEM); The crystallite size and phase characteristic of the product were determined by using the XRD pattern Compositional analysis of the as-prepared samples was performed by Fourier transform infrared spectroscopy (FT-IR) The morphologies and size of the samples were obtained by field emission scanning electron microscopy (FESEM) and Transmission electron microscopy (TEM) Experimental results obtained in this study clearly demonstrate that SiO2@C@graphene composites are an effective adsorbent for heavy metals The amount of heavy metal has reduced 100 % from (10mg/L) at the concentration, in the fixation 10ppm, amid an hour, analyzed by using Atomic absorption Spectroscopy (AAS) 33 Therefore, it is recommended that SiO2@C@graphene composites arranged here could be a promising applicant sorbent material for expelling heavy metal particles from aqueous The extraordinary physicochemical properties of the SiO2@C@graphene composites materials will assume a vital part in ecological contamination administration later on of human being 5.2 Conclusion This study shown that SiO2@C@graphene composites have provided great electrochemical properties The process have been set up by a hydrothermal method, this methodology understands the arrangement of carbocoatings on the surfaces of SiO2 nanoparticles and the great scattering of graphene nanosheets in the SiO2@C network at the same time The carbon covering in the composite could limit contact amongst SiO2 and electrolyte and cradle volume changes amid cycling, prompting enhanced cycling steadiness Then, the very much scattered graphene sheets could guarantee a high electrical conductivity of the composite electrode, bringing about the attractive limit, great cycling dependability, and predominant rate ability The combination procedure of SiO2@C@graphene composites evaluated here could likewise be connected to enhance the cyclability and rate capacity of other electrode materials with extensive volume changes and low electrical conductivities 34 REFERENCES A Sabo,M Gani A, A Ibrahim (2013) Pollution Status of Heavy Metals in Water and Bottom Sediment of River Delimi in Jos, Nigeria American Journal of Environmental Protection, 47-53 A Erakhrumen, A Agbontalor (2007) Review Phytoremediation: an environmentally sound technology for pollution prevention, control and remediation in developing countries Educational Research and Review, 2, 151–156 Alloway, B J (2012) Heavy Metals in Soils Environmental Pollution, 3-9 Ayrat M Dimiev , James M Tour (2014) Mechanism of Graphene Oxide Formation Mechanism of Graphene Oxide, 3060-3061 Balasubramanian, R; He, J; Wang (2009) Control, Management, and Treatment of Metal Emissions from Motor Vehicles Heavy Metals in the Environment, 475–490 Bull, B M (2003) Hazards of heavy metal contamination Impact of environmental pollution on health: Balancing risk, 167-182 doi:10.1093/bmb/ldg032 Chilvers DC, Peterson PJ (1987) Meema KM (eds) Lead, Mercury, Cadmium and Arsenic in the Environment Global cycling of arsenic, 279–303 D Mohan and C U Pittman Jr (2007) Arsenic removal from water/wastewater using adsorbents—a critical review Journal of Hazardous Materials, 153 E Pehlivan, A M ệzkan, S Dinỗ, and S Parlayici (2009) Adsorption of Cu2+ and Pb2+ ion on dolomite powder Journal of Hazardous Materials, vol 167, no 1–3, pp 1044–1049 European Commission DG ENV E3 (2002) Heavy Metals in Waste, Final Report Project ENV.E.3/ETU/2000/0058 E3 Retrieved from http://ec.europa.eu/environment/waste/studies/pdf/heavy_metalsreport.pdf Fabián F, Fernando L, Prócoro G , Silvia L , Elsa N A , Arturo I M , María del S, Gildardo Hernández-M, Raúl Herrera M , Manuel Antonio A and Ixchel R (2013) Heavy metal pollution in drinking water - a global risk for human health: A review African Journal of Environmental Science and Technology, 567-584 doi:DOI: 10.5897/AJEST12.197 Franỗois Perreault, Andreia Fonseca de Faria, Menachem Elimelech (2015) Environmental applications of graphene-based Chemical Society Reviews doi:DOI: 10.1039/c5cs00021a Gao W, Majumder M, Alemany L, Tharangattu N, Miguel A, Bhebendra K, Pradhan, Pulickel M (2011) Engineered Graphite Oxide Materials for application in water purification American Chemical Society, 3(6):1821-1826 Gao, W (2012) Graphite Oxide: Structure, Reduction and Applications 16 - 31 Gebhardt, K A (1976) Effects of Heavy Metals (Cadmium, Copper, and Mercury) on Reproduction, Growth, and Survival of Brine All Graduate Theses and Dissertation, 21-23 35 George L Trigg, Edmund H Immergut (1992) Combustion to Diamagnetism (Vol 4) VCH H A Andrianisa, A Ito, A Sasaki, J Aizawa, and T Umita (2008) Biotransformation of arsenic species by activated sludge and removal of bio-oxidised arsenate from wastewater by coagulation with ferric chloride Water Research, 4809–4817 J Chronopoulos, C Haidouti, A Chronopoulou, I Massas (1997) Variations in plant and soil lead and cadmium content in urban parks in Athens Sci Total Environ, 196:91–8 J, E (2011) Nature's Building Blocks new edition, Oxford University Press, Oxford, ISBN 978-0-19-960563-7 J H Traunfeld, D L Clement (2001) Lead in Garden Soils Home and Garden Maryland Cooperative Extention, University of Maryland Retrieved from http://www.hgic.umd.edu/_media/documents/hg18.pdf Jarup L, Berglund M, Elinder CG, Nordberg G, Vahter M (1998) Health effects of cadmium exposure—a review of the literature and a risk estimate Scand J Work Environ Health, 1–51 M N V Prasad, H M De Oliveira Freitas (2003) Metal hyperaccumulation in plants— biodiversity prospecting forphytoremediation technology Electronic Journal of Biotechnology, 6, 110–146 Matschullat, J (2000) Arsenic in the geosphere—a review Science of the Total Environment, 297-312 Mc Murry, John (2003) Fundamentals of Organic Chemistry (Fifth ed.) P Chutia, S Kato, T Kojima, and S Satokawa (2009) Arsenic adsorption from aqueous solution on synthetic zeolites Journal of Hazardous Materials, 440–447 Radojevic, M; Bashkin, VN (1999) Practical Environmental Analysis Royal Society of Chemistry, 406 Ruchita Dixit, Wasiullah, Deepti Malaviya, Kuppusamy Pandiyan, Udai B Singh, Asha Sahu, Renu Shukla, Bhanu P Singh, Jai P Rai, Pawan Kumar Sharma, Harshad Lade, Diby Paul (2015) Bioremediation of Heavy Metals from Soil and Aquatic Environment: An Overview of Principles and Criteria of Fundamental Processes sustainability, 2189-2212 doi:10.3390/su7022189 Steenland K, Boffetta P (2000) Lead and cancer in humans: where are we now? Am J Ind Med 38: 295–9 T Raja Rajeswari, Namburu sailaja (2014) National Seminar on Impact of Toxic Metals, Minerals and Solvents leading to Environmental Pollution Impact of heavy metals on environmental pollution U S Environmental Protection Agency (2000) Introduction to Phytoremediation National Risk Management Research Laboratory Retrieved from http://www.cluin.org/download/remed/introphyto.pdf 36 U.S Department of Health and Human Services (2005) Division of Toxicology and Environmental Medicine Arsenic Retrieved from http://www.baltimorehealth.org/info/ATSDR%20fact%20sheet.pdf Water treatment (n.d.) Retrieved from Lenntech: http://www.lenntech.com/periodic/elements/cu.htm Wenzhong Tang , Baoqing Shan , Wenqiang Zhang, Hong Zhang, Lishuo Wang, Yuekui Ding (2014) Heavy Metal Pollution Characteristics of Surface Sediments in Different Aquatic Ecosystems in Eastern China: A Comprehensive Understanding Chinese Academy of Sciences Retrieved from http://dx.doi.org/10.1371/journal.pone.0108996 WHO (1995) Lead Environmental Health Criteria, 165 WHO (2001) Arsenic and Arsenic Compounds In Environmental Health Criteria (Vol 224) Geneva: World Health Organization WHO Regional Office for Europe (2001) chapter 6.7, Lead In Air Quality Guidelines (2nd ed.) Copenhagen, Denmark Yurong Ren, Hengma Wei, Xiaobing Huang, , Jianning Ding (2014) A Facile Synthesis of SiO2@C@graphene Composites as Anode Material For Lithium Ion Batteries International Journal of ELECTROCHEMICAL SCIENCE, 7785-7790 37 ... research:" Applications of graphene- based nanomaterials (SiO2@C @graphene composites) to absorb heavy metal in water " 1.2 Research objective - Synthesis graphene oxide (GO), SiO2@C, SiO2 @C @Graphene composites. .. sorts of sustenance, in drinking water and in the air Therefore, we ingest prominent amounts of copper every day by eating, drinking, and relaxing The ingestion of copper is fundamental since... 1.4 kg (~2%) of light metals, and almost 68.6 kg of nonmetals (~98%) In everyday terms heavy metals speak to the heaviness of two dried peas, light metals a container of wine, and nonmetals possibly