Food Waste Materials Appear Efficient and Low-cost Adsorbents for the Removal of Organic and Inorganic Pollutants from Wastewater

Excessive release of organic and inorganic pollutants, due to urbanization and industrialization is a critical environmental problem worldwide [1]. In fact, discharge of wastewater from industrial activities releases effluents particularly rich in toxic and carcinogenic pollutants. In the last few years, environmental remediation was focused on the use of low cost adsorbents for the removal of metals and metalloids from wastewater.

There are several physic-chemical methods to remove elements from wastewater (chemical precipitation, solvent extraction, reverse osmosis, adsorption, ion exchange and chemical reduction) [1,2]. Adsorption is recognized as an effective and economic method because it offers high efficiency and flexibility in operation [3]. The adsorption phenomenon, in which the transfer of matter is provided from a gas, liquid or dissolved solid phase (adsorbate) to a solid biological adsorbent surface (biosorbent) in contact with it, can be called: “biosorption”.

Different biomaterials with high specific surface areas like activated carbons, resins and zeolites have been widely used for heavy metal wastewater treatment. However, to minimize the cost, alternative approaches have been developed using low cost materials such as agricultural waste by-products [4]. These include the use of modified clay [5,6], soil [7], seed powder [8], sugar cane bagasse [9], coffee and tea waste [10,11], neem bark [12] maize tassels [13], modified coconut fiber [14], coconut husk [15], rice husk [16], oil palm shell [17], fly ash, lime, agricultural ash and saw dust [18,19].

Among these low-cost materials, food waste adsorbents compete favourably in terms of cost, efficiency and ease of operation [20]. Moreover, with the aim of sustainable development, recycling food waste, which amounts to US $680 billion in industrialized countries and US $310 billion in developing countries [21], is beneficial. Food waste adsorbents do not require modification reaction like other materials used in adsorption processes [22]; technical applicability and cost advantages are two key factors for the selection of food waste as low-cost adsorbents for treating wastewater.

In recent studies, the adsorption capacity of several food waste materials (banana peel [22], apple peel [23], eggplant peel [24], potato peel [25], orange peel [26], lemon peel [27,28], watermelon peel [29,30], tomato peel [31], coffee waste [10,11,32,33] decaf coffee waste, carob peel and grape waste [34,35]) has been assessed by performing adsorption experiments in heterogeneous operating conditions (Figure 1).

Figure 1: Food waste materials’ processing [36].

In a latest study [37], the efficiency of such food waste materials for the removal of metals and metalloids from complex multielement solutions was evaluated in homogeneous experimental conditions, which allowed comparing the adsorption capacities of the individual adsorbents. The pH selected for the adsorption experiments were pH 2.0 and pH 5.5. The removal efficiency of the food waste adsorbents was also verified on a real polluted matrix; coffee waste and decaf coffee waste resulted the most efficient food waste adsorbents for the removal of Cu, watermelon peel for Pb and grape waste for Ni and Zn. This data confirmed the results obtained by the adsorption experiments performed in synthetic multi-element solutions. Banana peel, watermelon peel and grape waste resulted the most efficient and the least selective adsorbents for the removal of most of the metals and metalloids. Furthermore, the adsorbent surfaces of the food waste materials were analysed by FTIR spectroscopy and showed different types and amounts of functional groups, which demonstrated to act as adsorption active sites for various elements [37].

Considering the high efficiency of the examined low-cost adsorbents for the removal of inorganic pollutants, preliminary studies were conducted in our lab for assessing the potential of the investigated food waste materials to adsorb volatile organic compounds from a real polluted matrix of leachate. Some recent studies have shown the efficiency of low cost materials for the removal of industrial organic dyes [33,38,39], polycyclic aromatic hydrocarbons [40] and phenolic compounds [41]. However, the food waste adsorbents’ efficiency for the removal of volatile organic compounds was not investigated.

Our preliminary studies showed good adsorption capacities of the examined food waste materials for aliphatic and aromatic hydrocarbons. Therefore, it is worth to carry out further studies about volatile organic compounds’ removal by food waste adsorbents.

1. Fu F, Wang Q (2011) Removal of heavy metal ions from wastewaters: a review. Journal of environmental management 92(3): 407-418.
2. Owlad M, Aroua MK, Daud WAW, Baroutian S (2009) Removal of hexavalent chromium-contaminated water and wastewater: a review. Water air and soil pollution 200(1-4): 59-77.
3. Kamar FH, Craciun ME, Nechifor AC (2014) Heavy metals: sources, health effects, environmental effects, removal methods and natural adsorbent material as low-cost adsorbent: short review. Int J Scientific Engineer Technol Res 3(14): 2974-2979.
4. Hegazi HA (2013) Removal of heavy metals from wastewater using agricultural and industrial wastes as adsorbents. HBRC Journal 9(3): 276-282.
5. Singh SP, Ma LQ, Harris WG (2001) Heavy metal interactions with phosphatic clay. Journal of Environmental Quality 30(6): 1961-1968.
6. Stathi P, Litina K, Gournis D, Giannopoulos TS, Deligiannakis Y (2007) Physicochemical study of novel organoclays as heavy metal ion adsorbents for environmental remediation. Journal of Colloid and Interface science 316(2): 298-309.
7. Covelo EF, Vega FA, Andrade ML (2006) Heavy metal adsorption and desorption by a Eutric Regosol and a District Regosol. Geophysical Research Abstracts 8: 04553.
8. Mataka LM, Henry EMT, Masamba WRL, Sajidu SM (2006) Lead remediation of contaminated water using Moringa Stenopetala and Moringa oleifera seed powder. International Journal of Environmental Science & Technology 3(2): 131-139.
9. Mohan D, Singh KP (2002) Single-and multi-component adsorption of cadmium and zinc using activated carbon derived from bagasse-an agricultural waste. Water Research 36(9): 2304-2318.
10. Tan WT (1985) Copper (II) adsorption by waste tea leaves and coffee powder. Pertanika 8(2): 223-230.
11. Agwaramgbo L, Lathan N, Edwards S, Nunez S (2013) Assessing lead removal from contaminated water using solid biomaterials: Charcoal, coffee, tea, fishbone, and caffeine. Journal of Environmental Protection 4(7): 741.
12. Ayub S, Ali SI, Khan NA (2001) Efficiency evaluation of neem (Azadirachta indica) bark in treatment of industrial wastewater. Environ Pollut Control J 4: 34-38.
13. Zvinowanda CM, Okonkwo JO, Shabalala PN, Agyei NM (2009) A novel adsorbent for heavy metal remediation in aqueous environments. Int J Environ Sci Technol 6(3): 425-434.
14. Igwe JC, Abia AA, Ibeh CA (2008) Adsorption kinetics and intraparticulate diffusivities of Hg, As and Pb ions on unmodified and thiolated coconut fiber. Int J Environ Sci Technol 5(1): 83-92.
15. Tan WT, Ooi ST, Lee CK (1993) Removal of chromium (VI) from solution by coconut husk and palm pressed fibres. Environ Technol 14(3): 277- 282.
16. Srinivasan K, Balasubramanian N, Ramakrishna TV (1998) Studies on chromium removal by rice husk carbon. Indian J Environ Health 30: 376- 387.
17. Khan NA, Shaaban MG, Hassan MA (1998) Removal of heavy metal using an inexpensive adsorbent. Proceedings of UM Research Seminar, University of Malaya, Kuala Lumpur, Malaysia, pp. 1-5.
18. Ajmal M, Rao RAK, Siddiqui BA (1996) Studies on removal and recovery of Cr (VI) from electroplating wastes. Water Res 30(6): 1478-1482.
19. Aliabadi M, Morshedzadeh K, Soheyli H (2006) Removal of hexavalent chromium from aqueous solution by lignocellulosic solid wastes. International Journal of Environmental Science & Technology 3(3): 321-325.
20. Mohammed MA, Shitu A, Tadda MA, Ngabura M (2014) Utilization of various agricultural waste materials in the treatment of industrial wastewater containing heavy metals: a review. International Research Journal of Environmental Science 3(3): 62-71.
21. Gustavsson J, Cederberg C, Sonesson U, Emanuelsson A (2013) The methodology of the FAO study: global food losses and food waste-extent, causes and prevention. FAO.
22. Mallampati R, Valiyaveettil S (2013) Apple peels: a versatile biomass for water purification. ACS Applied Materials & Interfaces 5(10): 4443- 4449.
23. Ibrahim TH, Babar ZB, Khamis MI (2015) Removal of lead (II) Ions from aqueous solution using eggplant peels activated charcoal. Separation Science and Technology 50(1): 91-98.
24. Aman T, Kazi AA, Sabri MU, Bano Q (2008) Potato peels as solid waste for the removal of heavy metal copper (II) from waste water/industrial effluent. Colloids and Surfaces B: Biointerfaces 63(1): 116-121.
25. Ugbe FA, Pam AA, Ikudayisi AV (2014) Thermodynamic properties of chromium (III) ion adsorption by sweet orange (Citrus sinensis) peels. American Journal of Analytical Chemistry 5(10): 666.
26. Razafsha A, Ziarati P (2016) Removal of heavy metals from oryza sativa rice by sour lemon peel as bio-sorbent. Biomedical and Pharmacology Journal 9(2): 543-553.
27. Arslanoglu H, Altundogan HS, Tumen F (2009) Heavy metals binding properties of esterified lemon. Journal of Hazardous Materials 164(2-3): 1406-1413.
28. Lakshmipathy R, Sarada NC (2013) Application of watermelon rind as sorbent for removal of nickel and cobalt from aqueous solution. International Journal of Mineral Processing 122: 63-65.
29. Lakshmipathy R, Vinod AV, Sarada NC (2013) Watermelon rind as biosorbent for removal of Cd2+ from aqueous solution: FTIR, EDX, and Kinetic studies. J Indian Chem Soc 90: 1147-1154.
30. Lakshmipathy R, Vinod AV, Sarada NC (2013) Watermelon rind as biosorbent for removal of Cd2+ from aqueous solution: FTIR, EDX, and Kinetic studies. J Indian Chem Soc 90: 1147-1154.
31. Mallampati R, Valiyaveettil S (2012) Application of tomato peel as an efficient adsorbent for water purification-alternative biotechnology? RSC Advances 2(26): 9914-9920.
32. Kyzas GZ (2012) Commercial coffee wastes as materials for adsorption of heavy metals from aqueous solutions. Materials 5(10): 1826-1840.
33. Kyzas GZ, Bikiaris DN, Kostoglou M, Lazaridis NK (2013) Copper removal from aqueous systems with coffee wastes as low-cost materials. In E3S Web of Conferences. EDP Sciences 1.
34. Polat S, Putun E, Kilic M, Putun AE (2013) Biosorption of Cu (II) from aqueous solution by grape waste: Equilibrium, Kinetics and Thermodynamics. Journal of Selcuk University Natural and Applied Science, pp. 108-119.
35. Dwyer K, Hosseinian F, Rod M (2014) The market potential of grape waste alternatives. Journal of Food Research 3(2): 91.
36. Climate Change. North American initiative on food waste reduction and recovery.
37. Massimi L, Giuliano A, Astolfi ML, Congedo R, Masotti A, et al. (2018) Efficiency evaluation of food waste materials for the removal of metals and metalloids from complex multi-element solutions. Materials 11(3): 334.
38. Ali I, Asim M, Khan TA (2012) Low cost adsorbents for the removal of organic pollutants from wastewater. Journal of Environmental Management 113: 170-183.
39. Crini G (2006) Non-conventional low-cost adsorbents for dye removal: a review. Bioresource Technology 97(9): 1061-1085.
40. Crisafully R, Milhome MAL, Cavalcante RM, Silveira ER, De Keukeleire D, et al. (2008) Removal of some polycyclic aromatic hydrocarbons from petrochemical wastewater using low-cost adsorbents of natural origin. Bioresource Technology 99(10): 4515-4519.
41. Ahmaruzzaman M (2008) Adsorption of phenolic compounds on lowcost adsorbents: a review. Advances in Colloid and Interface Science 143(1-2): 48-67.