The document discusses adsorption as a wastewater treatment method. It covers the classification of adsorption, common adsorbent materials like activated carbon, and applications of adsorption such as in water and wastewater treatment plants. Recent developments discussed include using modified adsorbents like nano-based materials and biomass-derived carbons, which can have enhanced adsorption capabilities compared to traditional adsorbents. The conclusion emphasizes that adsorption is a relatively affordable treatment option and that further research on green technologies could make safer water access more sustainable.

1. Adsorption for wastewater treatment
SCHOOL OF ENVIRONMENTAL
SCIENCE AND ENGINEERING
COURSE: ADVANCED PHYSICO-
CHEMICAL TREATMENT
TECHNOLOGY OF WASTEWATER
JEAN PAUL NKUNDABOSE-
1919021014

2. Presentation outline
• Introduction
• Classification of adsorption
• Materials of adsorbent
• Application of adsorption
• Recent development of adsorption

3. Introduction
• Adsorption is the accumulation or concentration of substances at
a surface or interface.
• The adsorbing phase is termed the adsorbent and the material
being adsorbed the adsorbate.
• The process for adsorbates to release from adsorbent surfaces
into water –Desorption
• Adsorption can occur between two phases, namely liquid–liquid,
gas–liquid, gas–solid, or liquid–solid interfaces.
• When activated carbon is used, the adsorbing phase is a solid.

5. Adsorption classification
• According to the surface
adsorption capabilities of
adsorbents:
• Physisorption-induced by
van der Waals forces
• Chemisorption-the
adsorbate undergoes
chemical interaction with
the adsorbent
• Ion-exchange adsorption

6. Adsorption classification

7. Adsorption classification

8. Materials of adsorbent
• Activated Carbon- Produced through molding, carbonization and
activation of coal or wood material; lignite, peat, nut shell, coconut
shell, lignin, petroleum coke, and synthetic high polymers.
• Category: Granular activated carbon (GAC) & Powdered
activated carbon (PAC)

9. Materials of adsorbent
• Highly porous; with specific
surface area of 700 – 1200
m2/g
• Micropore: pore diameter < 4
nm, its internal surface area
taking up over 95% of the
total surface area
• Mesopore (transitional pore):
pore diameter: 4-100 nm,
occupying less than 5%
• Macropore: pore diameter >
100 nm, occupying less than 1%

10. Materials of adsorbent

11. Classes of organic compounds adsorbed
on activated carbon

12. Application of adsorption
Water treatment
Wastewater treatment (Secondary & tertiary treatment)
At the current state of development, integrated systems are basically divided
into two based on the configuration of the biomass:
 Suspended-growth biological systems receiving activated carbon dosage:
Powdered Activated Carbon Treatment (PACT) process and the PAC added
membrane bioreactor (PAC-MBR) process.
Attached-growth (biofilm) biological systems containing GAC media, namely
the Biological Activated Carbon (BAC) process.

13. Use of PAC in secondary treatment of wastewaters

14. Use of GAC in tertiary and secondary treatment of wastewaters

15. Recent development of adsorption
 Shift from conventional adsorbents to modified and nano-based
adsorbents

16. Removal of pharmaceutical contaminants
Removal process of antibiotics during anaerobic treatment of swine wastewater
• Tetracycline antibiotics were mainly removal via biosorption onto anaerobic
system.
• Biodegradation was the dominant removal mechanism for sulfonamide antibiotics.
• The adsorption of tetracycline antibiotics was a heterogeneous chemisorption
process.
• The degradation of SMs was via the cometabolism by specific microbial
communities.
Nano-based adsorbent and photocatalyst use for pharmaceutical contaminant
removal during indirect potable water reuse
• New materials that incorporate graphene-based nanomaterials have been
developed and shown to have increased adsorptive capabilities toward
pharmaceuticals when compared with unmodified graphene.
• In addition, adsorbents have been incorporated in membrane technologies

17. Removal of pharmaceutical contaminants

18. Use of Biomass derived carbon for enhanced adsorption
 Incorporation of humic acid into biomass derived carbon for
enhanced adsorption of phenol
• The biomass (rice husk) derived carbon decorated with humic acid
(HC), was synthesized through impregnation method for the adsorption
of phenol from water environment.
• Humic acids contain more oxygen-containing functional groups and
hydrogen bonds, which promotes the binding between HC and phenol
molecules.
• The adsorption performance of HC to phenol was better than that of
commercial activated carbon
• Langmuir model was more suitable for the equilibrium adsorption data
fitting, indicating that the adsorption mechanism of phenol on carbon
surface tends to be monolayer adsorption.
• Prepared carbon based materials can be employed as highly efficient
adsorbents used for the disposal of organic pollutants

19. Use of Biomass derived carbon for enhanced adsorption
Effective removal of anionic textile dyes using adsorbent
synthesized from coffee waste
• Adsorption of Reactive Black 5 and Congo Red from aqueous
solution by coffee waste modified with polyethylenimine (PEI-
CW) was investigated.
• Batch adsorption demonstrated that PEI-CW is more effective
in removal of RB5 than CR dye, due to the presence of four
negatively-charged sulfonate groups in RB5 dye structure which
can form stronger electrostatic interaction with the adsorbent.
• The maximum adsorption capacities of PEI-CW according to the
Langmuir isotherm model were found to be 77.52 mg/g (RB5)
and 34.36 mg/g (CR) respectively.

20. Use of Biomass derived carbon for enhanced adsorption
• Engineered biochar with anisotropic layered double hydroxide
nanosheets to simultaneously and efficiently capture Pb2+ and CrO4 2-
from electroplating wastewater
• A novel flower-like anisotropic MgAl layered double hydroxide
(MgAl-LDH)/ engineered biochar (BC) was synthesized.
• Cationic Pb2+ and anionic CrO4 2- can be simultaneously captured by
MgAl-LDH/BC.
• CrO4 2- was mainly removed via reduction, and subsequently
isomorphic substitution.
• The mechanism for Pb2+ removal was the complexations and
electrostatic attraction.
• The fixed-bed column evaluated the feasibility of MgAl-LDH/BC.

21. Use of Biomass derived carbon for enhanced adsorption

22. Use of Biomass derived carbon for enhanced adsorption
Biological performance and fouling mitigation in the biochar-amended anaerobic
membrane bioreactor (AnMBR) treating pharmaceutical wastewater
• The biochar with adsorption capacity of biopolymers was added in AnMBR to
investigate its potential in treating pharmaceutical wastewater and alleviating
membrane fouling.
• Adsorbable organic halogen (AOX) was removed effectively, and more COD was
biotransformed into CH4.
• Membrane fouling mitigation was achieved in the third stage with a 56%
decrease of average transmembrane pressure difference (TMP) rising rate.
• Oliveira et al also studied about alleviating sulfide toxicity using biochar during
anaerobic treatment of sulfate-laden wastewater.
• Biochar removed >98% of gaseous H2S and 94% of dissolved sulfide

23. Use of Biomass derived carbon for enhanced adsorption

24. Use of zeolitic waste as adsorbents
• Three types of zeolitic waste were used: unmodified zeolitic waste with two
different particle size distributions and H2O2-modified zeolitic waste.
• X-ray diffraction (XRD) analysis, Fourier transform infrared spectroscopy
(FT-IR), Brunauer-Emmett-Teller (BET) multilayer adsorption theory
measurements, and X-ray fluorescence analysis (XRF) were used to
demonstrate experimentally that the zeolitic waste could be used as a
sorbent for the water decontamination of NH4 + ions.
• The investigated zeolitic materials were mesoporous (4.84 nm) and
microporous (0.852 nm).,
• Zeolitic waste from the oil industry showed good NH4+ sorption properties
(removal efficiency of 72%), thus becoming a potential adsorbent to be
used in the treatment of contaminated aqueous effluents polluted with NH4
+ ions

25. Use of polymers
Preparation of a magnetic polystyrene nanocomposite for dispersive
solid-phase extraction of copper ions in environmental samples
• The core shell nanostructure of magnetic polystyrene (PS@Fe3O4)
was prepared.
• This adsorbent showed a significant uptake rate, more than 99.2% for
real samples
• The Cu (II) removal data were well fitted to the pseudo second-
order kinetic model and the Freundlich adsorption model
• This revealed that the adsorption of Cu (II) onto the PS@Fe2O3 was
a reversible and not restricted to the formation of monolayer.

26. Conclusion
• Compared to other advanced treatments, adsorption is not
costly.
• Recent developments also show some advantages as well as
some drawbacks. This indicates a need of research in Water
and Wastewater treatment industry.
• Overall, providing more reliable and affordable access to
safer water and sustainable environment will require green
technological innovation.

27. References
• Fanourakis, S. K., Peña-Bahamonde, J., Bandara, P. C., & Rodrigues, D. F. (2020). Nano-based adsorbent and
photocatalyst use for pharmaceutical contaminant removal during indirect potable water reuse. Npj Clean
Water. https://doi.org/10.1038/s41545-019-0048-8
• Mehdinia, A., Salamat, M., & Jabbari, A. (2020). Preparation of a magnetic polystyrene nanocomposite for
dispersive solid-phase extraction of copper ions in environmental samples. Scientific Reports.
https://doi.org/10.1038/s41598-020-60232-x
• Song, M., Song, B., Meng, F., Chen, D., Sun, F., & Wei, Y. (2019). Incorporation of humic acid into biomass
derived carbon for enhanced adsorption of phenol. Scientific Reports. https://doi.org/10.1038/s41598-019-
56425-8
• Vaičiukynienė, D., Mikelionienė, A., Baltušnikas, A., Kantautas, A., & Radzevičius, A. (2020). Removal of
ammonium ion from aqueous solutions by using unmodified and H2O2-modified zeolitic waste. Scientific
Reports. https://doi.org/10.1038/s41598-019-55906-0
• Wong, S., Ghafar, N. A., Ngadi, N., Razmi, F. A., Inuwa, I. M., Mat, R., & Amin, N. A. S. (2020). Effective
removal of anionic textile dyes using adsorbent synthesized from coffee waste. Scientific Reports.
https://doi.org/10.1038/s41598-020-60021-6
• Wang, H., Wang, S., Chen, Z., Zhou, X., Wang, J., Chen, Z., Engineered biochar with anisotropic layered
double hydroxide nanosheets to simultaneously and efficiently capture Pb2+ and CrO4 2- from electroplating
wastewater, Bioresource Technology (2020), doi: https://doi.org/10.1016/j.biortech.2020.123118

28. References
• Chen, L., Cheng, P., Ye, L., Chen, H., Xu, X., Zhu, L., Biological performance and fouling mitigation in the
biochar-amended anaerobic membrane bioreactor (AnMBR) treating pharmaceutical wastewater, Bioresource
Technology (2020), doi: https://doi.org/10.1016/j.biortech.2020.122805
• Oliveira, F.R., Surendra, K.C., Jaisi, D.P., Lu, H., Unal-Tosun, G., Sung, S., Khanal, S.K., Alleviating sulfide
toxicity using biochar during anaerobic treatment of sulfate-laden wastewater, Bioresource Technology
(2019), doi: https://doi.org/10.1016/j.biortech.2019.122711
• Çeçen, F., & Aktaş, Ö. (2011). Fundamentals of Adsorption onto Activated Carbon in Water and Wastewater
Treatment. In Activated Carbon for Water and Wastewater Treatment (pp. 13–41).
https://doi.org/10.1002/9783527639441.ch2
• Crittenden, J. C., Trussell, R. R., Hand, D. W., Howe, K. J., & Tchobanoglous, G. (2012). MWH’s Water
Treatment: Principles and Design: Third Edition. In MWH’s Water Treatment: Principles and Design: Third
Edition. https://doi.org/10.1002/9781118131473