Removal of Cu(II) ions from aqueous solution effluent using by z4uR7z

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									                                                   Removal of Cu(II) ions from
Department of Chemical & Process Engineering




                                                 aqueous solution effluent using
                                                 Melamine-Formaldehyde-DTPA
                                               resin in a fixed-bed up-flow column
                                                                 By

                                                          Ahmad Baraka
                                                            Supervisors

                                                          Prof. Peter Hall
                                                         Dr. Mark Heslop
                                                               The problem
Department of Chemical & Process Engineering



                                               Sources of pollution (Mining-industrial activities-
                                                           agricultural runoff, etc...)

                                                  Discharging heavy metals into water bodies

                                                                      Non-degradable

                                                        Accumulation of toxic heavy metals
                                                             (World wide problem)

                                               Some famous heavy metals present in different wastewaters:
                                               Chromium, Lead, Copper, Zinc, Cadmium, Nickel, Iron, Cobalt,
                                               Mercury, Silver, Aluminium, …..
                                                       How to solve the problem?
Department of Chemical & Process Engineering


                                                           The main methods for heavy
                                                                  metals removal
                                               ►   Chemical precipitation (hydroxides and carbonates)
                                               ►   Solvent extraction (liquid / liquid extraction)
                                               ►   Ion Exchange
                                               ►   Electrochemical method (Electrodialysis – Electrochemical
                                                   ion exchange (EIX)
                                               ►   Reverse osmosis (Membrane separation)
                                               ►   ADSORPTION (liquid / solid extraction)
                                                        - Active carbon, fly ash, etc..
                                                        - biomaterials (e.g. wastes of agricultural origin)
                                                        - inorganic resins
                                                        - organic resins
                                                                Adsorption
Department of Chemical & Process Engineering



                                               Adsorption is an attractive technology for treatment
                                               of wastewater for retaining heavy metals from dilute
                                                                     solutions.

                                                Adsorption (liquid/solid extraction):
                                                - physical adsorption (weak forces)

                                                 - chemical adsorption (chemical bond)

                                                 - surface micro-precipitation adsorption

                                                 - coordination adsorption (ligands or chelates
                                                    and depend on O,N,S,P donor atoms)
                                                           Aim of the project
Department of Chemical & Process Engineering



                                               ►   Synthesis and characterization of a new
                                                   organic resin (MF-DTPA) .

                                               ►   Studying adsorption performance of MF-DTPA
                                                   towards some heavy metals (Cu, Co, Cd, and
                                                   Zn) through thermodynamics, kinetics, and
                                                   isotherm. (batch study)

                                               ►   Estimate the adsorption mechanisms.

                                                   Examine the new adsorbent under continuous
                                                   mode (column study) considering Cu(II) ion
                                                               Why MF resin?
                                                                     (Advantages)
Department of Chemical & Process Engineering


                                               ►   Availability of main precursors (Melamine and
                                                   Formaldehyde) with low price.
                                               ►   Production of Monolithic, granules, fine powder
                                                   products.
                                               ►   Controllable porosity (pH, Temp., solvent type, solvent
                                                   content).
                                               ►   Good mechanical hardness.
                                               ►   Chemical and thermal stability.
                                               ►   Ability to functionalize with different
                                                    polyaminepolycarboxilic acids (e.g. DTPA, NTA, CDTA,
                                                   etc…)                 O         HO   O
                                                                                                  O
                                                                                     C
                                                                         C
                                                                    HO                             CH2 C
                                                                         CH2         CH2
                                                           DTPA           N
                                                                                 CH2     CH2
                                                                                                 N
                                                                                                         OH

                                                                    HO               N       CH2         OH
                                                                       C CH2 CH2                   CH2 C
                                                                       O                               O
                                                                Chemistry of preparation (MF-DTPA) resin
                                                                                   NH2                                                                        NH2
                                                                                                                 O                      +
                                                                                                                                                                                                 Methylol
                                                                               N       N                                                              N            N
                                                                                                   +         H           H
                                                                                                                                    H                                                                                   (A)
                                                                         H2N       N         NH2                                                 NH           N           NH    OH
Department of Chemical & Process Engineering


                                                                           Melamine                    Formaldehyde                              MATRIX
                                                                                                                                                       NH2
                                                                                                                                                                                                 Imine
                                                                                                                                                          N           N
                                                                                                                                        +
                                                                                                                                    H                                          CH2                                      (B)
                                                                                                                                                 HN            N           N
                                                                                                                                                  MATRIX
                                                   MF matrix formation



                                                                                                                                                MATRIX
                                                                                                                                             HN     HO                         OH                NH2
                                                                                                                                                 N                                       N
                                                                                                                                        +     N       NH                       NH                N
                                                                                                                                    H
                                                                                                                                                 N                                       N                              (C)
                                                                                                                                             HN                                                  NH          MATRIX
                                                                                                                                                      MATRIX
                                                                                                                                                              MATRIX
                                                                                                                     NH2                              HN                             NH2

                                                                                                                                                  N           N                  N           N
                                                                                                                                                                                                                        (D)
                                                                                       (A)                   N            N
                                                                                                   +                                                                                                         MATRIX
                                                                                                       H2N           N        NH2           HN         N         NH     NH     N                  NH
                                                                                                                                                               Methylene bridge
                                                                                                                                            MATRIX
                                                                                                                                                                      MATRIX
                                                                                                                                                              HN                                         NH2
                                                                                                                                                                                                                         (E)
                                                                                                                                                          N           N                              N       N
                                                                                                                                                                                                                    MATRIX
                                                                                       (A)         +         (A)                                 HN            N           NH    O      NH               N         NH
                                                                                                                                                  MATRIX                    Ether bridge

                                                                                                                                             MATRIX
                                                                                                                 NH2                                              NH                             NH2
                                                                                                                                                                                                                        (D)
                                                                                                         N            N                                    N           N                 N           N
                                                                                       (B)         +                                                                                                           MATRIX
                                               (amide bond)




                                                                                                   H2N           N           NH2                  HN              N         NH   NH              N        NH
                                                                                                                                                                             Aminal
                                                                                                                                                      MATRIX
                                               anchoring




                                                                                                                                                 MATRIX                                              O
                                                                                                                                                                                                                 M F-DTPA
                                                                                                                                             HN            N           NH      O
                                                                                                                                                                                                          OH
                                               DTPA




                                                                                                                                                      N           N                              N                        O
                                                                                                                                                                               N                               N
                                                                                                                                   DTPA                    NH                            OH          O                  OH
                                                                         (C)   and / or      (D)   and / or      (E)
                                                                                                                                                           MATRIX
                                                                                                                                                                                     O                    OH
                                               Proposed structure MF-DTPA resin
Department of Chemical & Process Engineering




                                                                       Chelating site

                                               Resin
                                               matrix
Department of Chemical & Process Engineering




                                     MF




                          MF-DTPA




                 C=O


                   O-H
                                               IR spectra of MF and MF-DTPA
    C13-NMR of MF and MF-DTPA




                                     MF-DTPA

                                     MF


0       50   100         150   200         250
                   PPM
  N15-NMR of MF and MF-DTPA




                            MF-DTPA

                            MF


-400   -300   -200   -100             0

              ppm
                                                       Elemental analysis
Department of Chemical & Process Engineering




                                               From elemental analysis results, 36.7% of the resin mass
                                               is DTPA (around 0.93 mmole per gram of solid resin).



                                                    Resin                     C    :   H :   N :   O
                                                    MF-DTPA                  35.7 : 5.2 : 37.7 : 21.6
                                                    MF                       31.7 : 5.5 : 40.4 : 22.3


                                                    About 93.3 mmole DTPA per gram MF-DTPA resin
                                               N2 gas adsorption-desorption (BET)


                                                   Volume Adsorbed (cm3/g)
                                                                             300
Department of Chemical & Process Engineering



                                                                             250
                                                                             200
                                                                             150
                                                                             100
                                                                             50
                                                                              0
                                                                                   0     0.2        0.4       0.6         0.8        1
                                                                                               Relative Pressure (P/Po)



                                                                                                                                Average
                                                  BET                                               BJH Adsorption
                                                           Micropore                                                              pore
                                                 Surface                                            cumulative pore
                                                           Area, m2/g                                                           diameter,
                                                Area, m2/g                                          volume., cm3 /g
                                                                                                                                   Å
                                                 161.863                               0.331              0.3965                 94.70
Department of Chemical & Process Engineering      SEM Image of MF-DTPA resin




                                               MF-DTPA aggregates
Department of Chemical & Process Engineering




                        Cu(II) adsorption
                       (continuous mode)
                                                       Experimental removal set
                                                             ( fixed-bed up-flow column)
Department of Chemical & Process Engineering




                                                              Sampling
                                                                valve                Packed
                                                                                     column
                                                          Influent




                                                                           flow
                                                          tank                        Effluent
                                               Peristaltic Pump                       tank
                                                   Suggested removal mechanism
                                                            (chelation)
Department of Chemical & Process Engineering




                                               Resin body             resin active part




                                                                       Cu(II)



                                                            Cu(II) coordination with DTPA part
                                                        Parameters to discuss
Department of Chemical & Process Engineering




                                               Effect of bed height            5     7     9 cm



                                               Effect of influent concentration 20   30    40 ppm



                                               Effect of influent flow rate    3.2   5.5   8.1 ml/min
                                                         Effect of bed height
Department of Chemical & Process Engineering



                                                                                         Flow rate=5.5 ml/min
                                                         1.2
                                                                                         C (initial)= 30 ppm
                                                          1        5 cm
                                                         0.8       7 cm
                                               C t/C o




                                                                   9 cm
                                                         0.6
                                                         0.4
                                                         0.2
                                                                                                10%
                                                          0
                                                               0    200            400           600
                                                                       time (min.)
                                                       Effect of influent concentration
Department of Chemical & Process Engineering



                                                                 20 ppm                  Flow rate=5.5 ml/min
                                                       1.2
                                                                                         Bed height = 7 cm
                                                        1        30 ppm
                                                       0.8       40 ppm
                                               Ct/Co




                                                       0.6
                                                       0.4
                                                       0.2
                                                                                               10%
                                                        0
                                                             0       200                400            600
                                                                           time (min)
                                                         Effect of influent flow rate
Department of Chemical & Process Engineering




                                                         1.2         3.2 ml/min       5.5 ml/min    8.1 ml/min
                                                          1
                                                         0.8
                                               C t/C o




                                                         0.6
                                                         0.4
                                                         0.2
                                                                                                    10%
                                                          0
                                                               0
                                               Flow rate=5.5 ml/min
                                                                      200         400         600    800
                                               C (initial)= 30 ppm                  time (min)
                                                Experimental results of up-flow column
                                                adsorption considering bed height, influent
                                                concentration and influent flow rate
Department of Chemical & Process Engineering




                                                                                      Veff    Tb       qm
                                               [Z(cm) ,C○ (mg l-1) , υ (ml min-1)]
                                                                                     (ml)    (min)   (mg g-1)
                                                          [5, 30, 5.5]               1072    195      27.62
                                                          [7, 30, 5.5]               1788    320      32.26
                                                          [9, 30, 5.5]               2530    460      33.43
                                                          [7, 20, 5.5]               2475    450       29.2
                                                          [7, 40, 5.5]               1403    255      33.31
                                                          [7, 30, 3.2]               2212    660      48.49
                                                          [7, 30, 8.1]               1296    160      19.25
                                                      Thomas model (Kinetics)
Department of Chemical & Process Engineering




                                                The data collected in continuous mode studies was
                                               used to determine the kinetic parameters using the
                                               Thomas model which is widely used for column studies.

                                                The Thomas model has the following expression;
                                               Parameters predicted from                                               5                      height
                                               Thomas model considering
                                                                                                                       4                                                    Z= 5 cm
                                                                                                                       3                                                    Z= 7 cm
                                               bed height, influent




                                                                                                  ln(C o/C t - 1)
                                                                                                                       2
                                                                                                                                                                            Z= 9 cm
                                                                                                                       1
                                               concentration and influent
Department of Chemical & Process Engineering


                                                                                                                       0
                                                                                                                      -1100                  300                  500
                                               flow rate                                                              -2
                                                                                                                      -3
                                                                                                                      -4                       time (min)
                                                [Z(cm) ,C○                      Q
                                                               kTh (lmg-1
                                                 (mg l-1) ,                    (mg      R2
                                               υ (ml min-1)]
                                                                 min-1)
                                                                               g-1)
                                                                                                                               4             concentration                   20 ppm
                                                                                                                               3
                                                                                                                                                                             30 ppm
                                               [5, 30, 5.5]                            0.974                                   2
                                                               1.17 × 10-3     21.97                                                                                         40 ppm




                                                                                                               ln(C o/C t-1)
                                                                                                                               1
                                                                                         8
                                                                                                                                0
                                               [7, 30, 5.5]                            0.976                                   -1100         300                      500
                                                               1.21 × 10-3     32.30
                                                                                         6                                     -2
                                                                                                                               -3
                                               [9, 30, 5.5]                            0.980
                                                               1.25 × 10-3     43.75                                           -4                  time (min)
                                                                                         0
                                               [7, 20, 5.5]                            0.959                         4                        Flow rate                      3.2 ml/min
                                                               1.50 × 10-3     29.69                                 3                                                       5.5 ml/min
                                                                                         3
                                                                                                                     2                                                       8.1 ml/min
                                               [7, 40, 5.5]                            0.970
                                                                                               ln(C o/C t-1)


                                                               1.32 × 10-3     33.16                                 1
                                                                                         2                           0

                                               [7, 30, 3.2]                            0.992                     -1 0                  200     400              600          800
                                                               9.13 ×   10-4   36.55                             -2
                                                                                         3
                                                                                                                 -3
                                               [7, 30, 8.1]                            0.984                                                   time (min)
                                                               1.42 × 10-3     26.13                             -4
                                                                BDST model
                                                          (Bed Depth Service Time)
Department of Chemical & Process Engineering


                                                              cm




                                               Minutes
                                                         BDST constants:
                                                         N○ = 7232 mg/ml (25.8 mg per gram of solid resin)
                                                         kad = 4.91×10-4 l mg-1 min-1
                                                         Z○ = 2.2 cm.
                                                                                     BDST model analysis
                                                                           600
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                                                     Service time (min.)
                                                                           500
                                                                           400                                            0.033
                                                                           300                                            0.1
                                                                           200                                            0.5
                                                                           100                                            0.9
                                                                            0
                                                                                 4     5    6         7           8   9         10
                                                                                                Bed height (cm)

                                                    BDST plots at Ct/C○ = 0.033, 0.1, 0.5 and 0.9.


                                               The BDST equations of these lines are as follows:
                                               Ts = 62.5 Z – 144.17 for Ct/C○ = 0.033         (R2=0.9995)
                                               Ts = 67.5 Z – 149.17 for Ct/C○ = 0.1           (R2=0.9995)
                                               Ts = 66.3 Z – 65.417 for Ct/C○ = 0.5           (R2=0.9999)
                                               Ts = 63.8 Z – 1.25   for Ct/C○ = 0.9           (R2=0.9988)
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                 2.2 cm
                                                BDST model fitting with influent concentration
                                                  condition and influent flow rate condition
Department of Chemical & Process Engineering




                                                                                                     BDST
                                                                                     Experimental
                                                                                                     model
                                               [Z(cm) ,C○ (mg l-1) , υ (ml min-1)]   service time
                                                                                                    time, TS
                                                                                        (min)
                                                                                                      (min)

                                                          [7, 20, 5.5]                   450          485

                                                          [7, 30, 5.5]                   320          324

                                                          [7, 40, 5.5]                   252          243

                                                          [7, 30, 3.2]                   660          663

                                                          [7, 30, 8.1]                   160          172
                                                               Regeneration and re-adsorption

                                                                                                     EDTA (0.01 M)
Department of Chemical & Process Engineering


                                                                                           Regeneration efficiency 84% (Ct/Co=1)



                                                                   9 bed volumes




                                                         1.2                First adsorption process
                                                          1
                                                                            Second adsorption
                                                         0.8                process
                                               C t/C o




                                                         0.6       Capacity decreased by 20% (Ct/Co=1)
                                                         0.4
                                                                             due to Hydrolysis
                                                         0.2
                                                          0
                                                               0            100          200          300          400             500
                                                                                        time (min)
                                                                Conclusions
Department of Chemical & Process Engineering


                                               ►   Instrumental analysis (IR, NMR, Elemental analysis, BET,
                                                   SEM) gave proof for synthesis success of the new
                                                   chelating resin, MF-DTPA and showed its high porosity .
                                               ►   The metal removal was due to strong chelating agent
                                                   (DTPA) which can coordinate several types of heavy
                                                   metals.
                                               ►   Thomas model fitted data and can be used to determine
                                                   capacity and rate constant.
                                               ►   High rate constant of removal.
                                               ►   The dynamic capacity is around 30 mg Cu(II) / g.
                                               ►   BDST model fitted data and can be used for scaling up
                                                   the system for practical application.
                                               ►   Regeneration by EDTA solution.
Department of Chemical & Process Engineering




                      THANK YOU

								
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