NOM Present in Biosorbent Peat for Decontamination of Water Containing Metallic Specie. Ana Paula dos S. Batista

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1 NOM Present in Biosorbent Peat for Decontamination of Water Containing Metallic Specie Ana Paula dos S. Batista

2 CHROMIUM 2

3 Cr(III) is a metal commonly found in wastewaters, and although thought to be an essential nutrient required for sugar and fat metabolism in organisms long-term exposure has been linked to skin allergies and cancer. Moreover, the metal can be oxidized to the more carcinogenic and mutagenic Cr(VI), which is toxic to human body tissue owing to its oxidizing potential and ability to permeate biological membranes 3

4 BIOSORPTION 4

Biosorption is a viable technique for metal removal from wastewaters. Humic substances are the main component of the natural organic matter (NOM) present in biosorbent peat.

5 Biosorption is a viable technique for metal removal from wastewaters. Humic substances are the main component of the natural organic matter (NOM) present in biosorbent peat. Typical carbon and hydrogen contents of peat are in the ranges 40 60% and 4 6%, respectively. High contents of carbon and organic matter are important characteristics, which influence the extent of metal uptake by the biosorbent. Fernandes et al.,removal of methylene blue from aqueous solution by peat, J. Hazard. Mater. 144 (2007)

6 only in the smallest state in Brazil Sergipe mineral reserve of 21 bogs: estimated at 800,000 t on a dry basis (CPRM - Research Center of Mineral Resources, Brazil). 6

7 Peat is a natural humic substance with recognized potential for wastewater treatment due to its ability to sequester metals. The abundance of alkyl-c functional groups plays an important role in complexation and ion exchange during metal ions fixation D. Mohan, C.U. Pittman Jr., Activated carbons and low cost adsorbents for remediation of tri- and hexavalent chromium from water, J. Hazard. Mater. 137 (2006)

8 OBJECTIVE 8

9 Objective 9 Investigate the performance of three different samples of peat, to check which has better adsorption capacity / removal of chromium (III) in aqueous solution. 9

10 PROCEDURE 10

11 Three peat samples were collected from different Brazilian states collected at a depth of 10 cm of peat bogs Santo Amaro das Brotas city- (SAO) Sergipe State Itabaiana city - (ITA) Sao Paulo State 11 Ribeirão Preto city- (SAP)

12 The raw peat was air-dried at room temperature and the material was then. sieved though a 9 mesh grid a) wet sample b) air drying d) after screening c) grinding, 12

Adsorpiton Experiment 13 Batch adsorption experiments were conducted in a constant

Fixed volumes of 50mL aliquots of aqueous 10.

flasks, adjusting the initial ph of solutions to a value of 5.

13 Adsorpiton Experiment 13 Batch adsorption experiments were conducted in a constant temperature shaker bath at 25±0.2 C and 125 rpm. Fixed volumes of 50mL aliquots of aqueous 10.0mgL 1 Cr(III) solution were added to 100mg of peat in stoppered polyethylene flasks, adjusting the initial ph of solutions to a value of 5.0 (except for the ph study) with either 0.1 moll 1 HCl or 0.1mol L 1 NaOH solution Millex-HV 0.45m syringe driven filter unit was used for removal of the supernatant for subsequent analysis.

14 After filtration, a Shimadzu Model AA-6800 atomic absorption spectrometer was used for detection of Cr(III) concentrations in the supernatant solutions. Each experiment corresponded to one datapoint, the sample being taken at predetermined time intervals up to a maximum of 72 h, without alteration of the final volume. 14

15 The amounts of Cr(III) adsorbed onto the peat were then calculated from the difference between the initial and final concentrations of the solution, using the equation: q = (c0 c)v m q - is the sorption capacity in mg of metal per g of dry peat C0 - the initial metal ion concentration in mgl 1 C - the final metal ion concentration in mgl 1 v - the volume of the liquid in L, and m the weight of the peat adsorbent in g After determining the time required for adsorption equilibration, the experiments were repeated at other initial ph values, in the range

16 16 Results and discussion

17 Peat Samples Caracterization 17

18 Scanning Electron Microscopy (a) SAO peat Santo Amaro das Brotas city, Sergipe Strands of plant material (b) SAP peat Ribeirão Preto city, São Paulo Mineral phase (c) ITA peat Itabaiana city, Sergipe 18

$X-ray diffractometry of peat samples (a) SAO peat Santo Amaro das Brotas city, Sergipe Amorphous matter$

19 X-ray diffractometry of peat samples (a) SAO peat Santo Amaro das Brotas city, Sergipe Amorphous matter (b) SAP peat Ribeirão Preto city, São Paulo (c) ITA peat Itabaiana city, Sergipe Crystalline Structures 19

20 The SEM, XRD and elemental analyses showed that only the SAO sample possessed true peat characteristics. Typical compositions of peat are in the range 40 60% C and 4 6% H Fernandes et al., J. Hazard. Mater. 144 (2007)

21 Adsorption Capacity

22 Maximum uptakes of chromium, at equilibrium ph ±0.01 mgg ±0.01 mgg ±0.01 mgg 1 22

quantities in Sergipe State estimated at 800,000 t on a dry basis (CPRM

23 Adsorption experiments investigating the influence of ph were undertaken using only the SAO peat due to Its ready availability in large quantities in Sergipe State estimated at 800,000 t on a dry basis (CPRM - Research Center of Mineral Resources, Brazil). its higher adsorption capacity. 23

24 ph Influence 24

25 Uptake by peat is usually ascribed to processes including: surface adsorption adsorption complexation complexation ion exchange 25

26 26 ion exchange Humification of peat produces humic substances possessing carboxylic and phenolic acid groups within their structures R O + M + R COOM H + + OH

metals Cr Speciation At low ph, competition with H

27 ph influence 27 Reducing the ph during adsorption Ion Exchange release protons on reaction with metals Cr Speciation At low ph, competition with H + At high ph, solubility; tending to precipitate as Cr(OH) 3

28 CONSIDERATIONS 28

29 carboxylic acid functional group two acidic functional groups on an aromatic ring can result in pka s of between 2.

29 Highest adsorption (retention >95.0%) was achieved at equilibrium ph 4.0 using the Santo Amaro das Brotas peat. Equilibrium ph values may be attributed to the buffering capacity of peat. 29 carboxylic acid functional group two acidic functional groups on an aromatic ring can result in pka s of between 2.9 (or lower) and 4.4. most significant buffering by humic substances occurs in ph range E. Tipping, Cation Binding by Humic Substances, Cambridge University Press, 2002

30 adsorption efficiency was associated with the amount of organic matter present 30

equation an equilibrium adsorption capacity, qmax, of 5.

31 Experimental data for the adsorption of Cr(III) from aqueous solution onto SAO peat were fitted to the Langmuir equation an equilibrium adsorption capacity, qmax, of 5.60mgg 1 close to the experimentally determined value 4.90±0.02 mgg 1 31

32 SAO peat From Sergipe State, Brazil a viable material for decontamination of effluents containing Cr(III) ions 32

33 Acknowledgements 33 financial support of this work: CAPES, FAPESP and CNPq brazilian agencies and Sergipe Federal University Prof. Dr. William J. Cooper for this opportunity

34 References TAHIR, S.S., NASEEM, R. Removal of Cr (III) from tannery wastewater by adsorption onto bentonite clay. Separation and purification technology. v. 53, p. 313, HAN, X., WONG, Y. S., TAM, N. F. Y. Surface complexation mechanism and modeling in Cr (III) biosorption by a microalgal isolate, Chlorella miniata. Journal of Colloid and Interface Science, v. 303, p. 365, VOLESKY, B. Detoxification of metal-bearing effluents: biosorption for the next century. Hydrometallurgy, v. 59, p , BAILEY, S.E., OLIN, T.J., BRICKA, R.M., ADRIAN, D.D. A review of potentially low-cost sorbents for heavy metals. Water Research. v. 33, p ,

35 EL-GEUNDI, M. S.; Adsorption Science Technology., v. 10, p. 777, MOHAN, D. PITTMAN, C. U. Jr. Activated carbon and low cost adsorbents for remediation of tri and hexavalent chromium from water. Journal of Hazardous Materials. v. 137, p , MALTERER, T., MCCARTHY, B., ADAMS, R. Use of peat in waste treatment. Mining engineering, p , DEAN, S. A., TOBIN, J. M. Uptake of chromium cations and anions by milled peat. Resources, Conservation and recycling, v. 27, p , MA, W., TOBIN, J. M. Determination and modelling of effects of ph on peat biosorption of chromium, copper and cadmium. Biochemical Engineering Journal. v. 18, p , MURALEEDHARAN, T. R., IYENGAR, L., VENKOBACHAR, C. Biosorption: an attractive alternative for metal removal and recovery. Current Science, n.61, n.6, p ,

36 PETRONI, S. L. G., PIRES, M. A. F. Adsorção de zinco e cádmio em colunas de turfa. Química nova, v. 23, p , GOSSET, T.; TRANCART, J. L.; THÉVENOT, D. R.; Batch metal removal by peat. Kinetics and thermodynamics. Water Research, v. 20, p , HARDIN, A. M., ADMASSU, W. Kinetics of heavy metal uptake by vegetation immobilized in a polysulfone or polycarbonate polymeric matrix. Journal of Hazardous Materials, B126, p , DAHBI, S., AZZI, M., SAIB, N., GUARDIA, M. de la, FAURE, R., DURAND, R. removal of trivalent chromium from tannery waste waters using boné charcoal. Anal. Bioanl. Chem., v. 374, p , DENG, S., BAI, R. Removal of trivalent and hexavalent chromium with aminated polyacrylonitrile fibers: performance and mechanisms. Water Research, v. 38, , GODE F., PEHLIVAN, E. Adsorption of Cr(III) ions by Turkish brown coals. Fuel Processing Technology, v. 86, ,

37 MOHAN, D. PITTMAN, C. U. Jr. Activated carbon and low cost adsorbents for remediation of tri and hexavalent chromium from water. Journal of Hazardous Materials. v. 137, p , CORNELIA, H., HORST, J., WOLFGANG, H. H., Application of the surface complex formation model to ion exchange equilibrium part. V. Adsorption of heavy metal salts onto weakly basic anion exchangers. React. Funct. Polym., v. 49, p , N.R. BISHNOI et al., Biosorption of Cr (III) from aqueous solution using algal biomass spirogyra spp., J. Hazard. Mater. (2006), doi: /j.jhazmat LI, Z., GUO, S., LI, L. Study on the process, thermodynamical isotherm and mechanism of Cr (III) uptake by Spirulina platensis. Journal of Food Engineering, v. 75, p. 129,

Biosorption of aqueous chromium VI by living mycelium of phanerochaete chrysosporium

Biosorption of aqueous chromium VI by living mycelium of phanerochaete chrysosporium Nikazar, M.*, Davarpanah, L., Vahabzadeh, F. * Professor of Department of Chemical Engineering, Amirkabir University