BACKGROUND OF THE STUDY
Clean water is the major priority in all countries in the world. According to the World Health Organization (WHO), access to clean water is one of the world’s most pressing issues. About 884 million people worldwide don’t have access to clean drinking water, in which humans and other living organisms die due to large portion of contaminated water-related diseases carried around every year. Urban rivers are losing attraction due to the problem of high turbidity in the water resources.
The rapid modernization and industrialization resulting from population boost plays a big role on the excessive release of pollution in the environment especially the water resources. For instance, heavy metals that are often found on processing industries such as mining. A lot of countries are suffering from scarcity of safe and clean water because of these. Moreover, consuming water that are contaminated with heavy metals from mining industries also affects the economic development of the country because water is a primary resource in different productive sectors including agricultural production, livestock and more.
SOCIETAL ISSUES
RELATED STUDIES AND LITERATURES
Compared to conventional water purification methods, use of bio-adsorbents such as banana peels, orange peels, rice husk, tea waste, sugarcane bagasse, pine bark and other peels could be advantageous owing to the low cost, ready availability, environmental friendliness and high efficiency.
In recent years, a growing research interest had been prompted to study on using fruit peels as bio- flocculants in their respective flocculation behavior in the wastewater treatment process. The development and application of banana peel was investigated for the remediation of heavy metals (Pb, Zn and Cr). The applicability of the sorption process was tested on wastewater. The banana peel adsorbent, together with 0.5 M H2SO4, showed the highest percentage removal of chromium ion (88.9 %) at a pH of 6. However, Sulfuric Acid (H2SO4) is a highly corrosive chemical that is potentially explosive in concentrated form that it can cause severe skin burns, can irritate the nose and throat and cause difficulties breathing if inhaled, can burn the eyes and possibly cause blindness, and can burn holes in the stomach if swallowed. In contrast to that, it was still confirmed that banana peel is a promising adsorbent for the removal of chromium from industrial effluent.
A professor from Bioscience Institute at Botucatu, Brazil, demonstrated how the fruit skins can outperform even conventional purifiers such as Aluminium Oxide, cellulose and silica. These have potentially toxic side effects and are expensive. The team's method follows previous work that showed that plant parts, such as apple and sugar cane wastes, coconut fibers and peanut shells, can remove toxins from water. These natural materials contain chemicals that have an affinity for metals. De Castro and colleagues dried the peels in the sun for a week, ground them and added them to river water containing known concentrations of copper and lead. They found that the peels absorbed 97 per cent of the metals after just one hour. The peels were tested in the lab and worked perfectly. Eventually their efficiency reduces, at which point the metals should be removed from the skins so that they can be disposed of safely. Castro said that, although the peels were tested only on copper and lead, the material could also work on cadmium, nickel and zinc.
Banana peels contain Sulfur, Nitrogen, and Carboxylic Acids. Researchers at Sao Pãulo State University in Brazil have found that when dried banana peels are ground, pressed into a tablet, and added to water (or used as a filter), they can remove copper and lead, making the water a lot purer than it was before. Consuming heavy metals like these can have devastating side effects; lead has been proven to affect the brain and nervous system.
Unfortunately, banana peels won’t remove pathogens like parasites, bacteria, or viruses, but it’s good that something as unassuming as a banana peel can have potentially world-changing effects.
Based from a Dickinson College chemistry professor, in her newly published research, she advanced the power of fruit and vegetable peels to remove pollutants, such as dyes and heavy metals, from water in which they performed water purification experiments using peels and seeds from more than a dozen varieties of foods—from pumpkin and okra to lemon and banana. She found that the peels removed Methylene blue, Lead and Copper through the process of adsorption, a chemical bonding of the pollutant molecules to the surface of the peels.
A study entitled “Removal of Heavy Metals from Water (Cu and Pb) Using Household Waste as an Adsorbent” also demonstrated Chicken eggshells, Banana peels and Pumpkins are used as good adsorbents for removing heavy metals from contaminated water, which have been observed and studied currently. The effects of various parameters such as pH, agitation speed and contact time was studied and good results were obtained at pH 7, 100 rpm and 90 mins of contact time. The results indicate that usage of household waste such as these can be used as a good biosorbent for removal of heavy metals on a large scale and create effective, cheap and efficient methods in treating wastewater.
Based from another study entitled “Pretreated Fruit Peels as Adsorbents for Removal of Dyes from Water”, three kinds of tropical fruit peel wastes, pomelo, orange and passion-fruit peels, were investigated as potential bioadsorbents for the extraction of dyes in water. It was found that these bio-peels efficiently adsorbed in a short time, within one hour. The dye removal efficiency of orange peels and passion fruit peels ranged from 82-92% while that of pomelo peels was faster with 91-94% depending on the initial concentration (200 ppm). The efficiency of dye removal increases significantly as adsorbent dosage increases, passion-fruit peels 43-98%, pomelo peels 67-94%, orange peels 57-93%.
From the study of entitled "Fruit and Vegetable Peels as Efficient Renewable Adsorbents for Removal of Pollutants from Water: A Research Experience for General Chemistry Students," the researchers analyzed the ability of avocado, hamimelon and dragon fruit peels to remove pollutants from water. They demonstrated how dried avocado peel can adsorb large amounts of methylene blue onto its surface in a matter of hours.
Researchers have been working harder than ever to find ways to purify water. The efficient approaches in tackling high turbidity problem in wastewater has been resolve by the researchers using the method of sedimentation and filtration. Many water purification methods such as chemical coagulation, photodegradation, precipitation, flocculation, activated sludge, membrane separation and ion exchange processes have been tested for removing the pollutants. Yet, it is difficult to find a single effective method that can remove all harmful pollutants from water.
Among the possible techniques for water treatments, the adsorption process by solid adsorbents shows potential as one of the most efficient methods for the treatment and removal of organic contaminants in wastewater treatment. Adsorption has advantages over the other methods because of simple design and can involve low investment in term of both initial cost and land required. The adsorption process is widely used for treatment of industrial wastewater from organic and inorganic pollutants and meet the great attention from the researchers. In recent years, the search for low-cost adsorbents that have pollutant –binding capacities has intensified. Materials locally available such as natural materials, agricultural wastes and industrial wastes can be utilized as low-cost adsorbents. Activated carbon is a commonly used adsorbent for removal of various pollutants from wastewater; however, its use is limited due to its high cost. Recently, a number of nonconventional adsorbents have been used due to their capability to remove different pollutants from wastewater .Nonconventional adsorbents are classified into five different categories: (1) waste materials from agriculture and industry, (2) fruit waste, (3) plant waste, (4) natural inorganic materials, and (5) bioadsorbents (living and nonliving biomass).
Adsorption is a surface phenomenon with common mechanism for organic and inorganic pollutants removal. When a solution containing absorbable solute comes into contact with a solid with a highly porous surface structure, liquid–solid intermolecular forces of attraction cause some of the solute molecules from the solution to be concentrated or deposited at the solid surface. The solute retained (on the solid surface) in adsorption processes is called adsorbate, whereas, the solid on which it is retained is called as an adsorbent. This surface accumulation of adsorbate on adsorbent is called adsorption. This creation of an adsorbed phase having a composition different from that of the bulk fluid phase forms the basis of separation by adsorption technology.
In a bulk material, all the bonding requirements (be they ionic, covalent, or metallic) of the constituent atoms of the material are filled by other atoms in the material. However, atoms on the surface of the adsorbent are not wholly surrounded by other adsorbent atoms and therefore can attract adsorbates. The exact nature of the bonding depends on the details of the species involved, but the adsorption process is generally classified as physicsorption (characteristic of weak Van Der Waals forces) or chemisorption (characteristic of covalent bonding). It may also occur due to electrostatic attraction.
With the processes mentioned above and to address water source concern on water shortage due to environmental waste, the researchers decided to utilize fruit peel wastes specifically the peel of Peanut Shells, Banana and Pomelo Peelings as substitute water purifiers, seeks to explore the effectiveness of its adsorption properties, and to determine how the fruit peels enhances the water quality.
SIGNIFICANCE OF THE
STUDy
Ascertaining the sensitive problems associated with access to clean water and high turbidity in water resources, alternative sources for this and finding a new way of water purification and filtration have become essential. This research intends to provide a significant alternative way that can be used in filtering water pollutants in contaminated water resources by using fruit peel wastes which are considered as the most prolific agricultural waste and utilizing it to its extent. Providing an alternative way of using fruit peels in water purification methods can be a promising design to help lessen water pollution and help consumers to lessen their expenses without having harm done to people, environment, other resources, and farmers who have been struggling with the disposal of this wastes. This study would also help reduce pollution by recycling waste in a meaningful way. The project can be used in all existing farms in the Philippines since the country is one of the major fruit producers.