The rapid development of industries and factories globally has resulted in significant environmental pollution, making it one of the most alarming issues of our time. Industrial and mining wastewater, often untreated, is among the most dangerous types of waste. Heavy metals from these sources seep into water and soil, absorbed by plants and animals, eventually entering the human food chain and causing severe health problems. Heavy metals are persistent environmental pollutants that can infiltrate ecosystems through industrial waste or garbage.
Researchers have identified heavy metals as highly detrimental substances that need to be removed from water and soil. Excessive amounts of heavy metals in soil and water pose significant threats to aquatic ecosystems, agriculture, and public health. These metals can enter the human body directly through contaminated water, air, and soil or indirectly through food, fruits, and meat from animals fed with contaminated feed.
Exposure to heavy metals can lead to various health issues, including skin problems, digestive and respiratory disorders, kidney and liver damage, and cancer. Metals such as chromium, arsenic, cadmium, mercury, and lead are particularly hazardous to health. Due to their destructive effects and serious health implications, it is crucial to remove and reduce heavy metals from the environment. Various methods are employed to remove heavy metals, including reverse osmosis, chemical deposition, ion exchange, membrane processes, evaporation, and solvent extraction. However, these methods often come with drawbacks, such as high equipment and production costs, energy requirements, and space needs, limiting their use.
Using adsorbents to remove heavy metals is a cost-effective and practical method, gaining considerable attention from researchers. Adsorption is advantageous due to its economic efficiency, metal selectivity, non-toxic nature, metal recovery capabilities, and overall effectiveness. In this study, soybean waste, a byproduct of the food industry, was used as an adsorbent. Soybean oil, which is rich in linoleic acid, is a key product of the food industry. Soybean oil waste, containing substantial amounts of linoleic acid and various hydroxyl and fatty acid groups, shows significant potential for metal ion adsorption.
In this study, soybean oil residues were washed two to three times with distilled water, dried at 60°C, and ground to the appropriate particle size for use in aqueous solutions for heavy metal adsorption experiments. The adsorption method used in this research is a widely applied technique due to its high yield and ease of application. Contaminated water is passed through a substrate or filter, and arsenic and heavy metals are separated from the water through bonds formed with the adsorbent.
The advantages of the adsorption method include its suitability for removing heavy metals from dilute solutions, low cost, and simple process design. The research findings indicate that increasing pH, contact time, adsorbent quantity, and adsorption rate can enhance the initial concentration of metal ions. The optimal pH for metal ion adsorption is around 3-5. The equilibrium time for cadmium ions is 40 minutes, for zinc ions is 20 minutes, and for lead ions is 10 minutes. The experiments demonstrated that the biosorbent effectively removes heavy metals from contaminated water, with hydronium ion concentration changes being a crucial factor in adsorption capacity. Results show that adsorption increases with contact time until equilibrium is reached. Additionally, increasing the adsorbent amount at a constant ion concentration improves adsorption efficiency.
This study concludes that using food industry waste as an adsorbent is a promising and economical method for heavy metal removal, offering a sustainable solution to one of the pressing environmental challenges.
Source Article : https://unair.ac.id/penghapusan-logam-berat-menggunakan-limbah-industri-makanan-sebagai-adsorben-murah/
Link Journal : https://www.scielo.br/j/cta/a/3h8N9ywqs4mtPYrFLLpW4cD/?lang=en&format=pdf