Water is the most essential piece of the puzzle on how the human body functions and is constantly being used to maintain cell, tissue and organ functions (Laskey and Sinha, 2019). Humans loose water through breathing, digesting and sweating so it is important to remain hydrated. However, water is constantly being recycled so any contamination can be hard to remove which can disrupt the cycle and can have harmful side effects such as acid rain or a person’s health can also be negatively affected. This study tested multiple ways to remove copper from a solution the most cost effective and simple way through coffee adsorption. Our experiment found a linear relationship between an increase in coffee particles and the percentage of copper removed. The results were obtained by using a spectrophotometer calculating the absorbance through the solution stained by Alizarin red solution which creates a complex with the copper ions. A high absorbance value corresponds to a darker solution containing more copper ions.
Fresh water makes up only 2.5% of the Earths water source but less than 0.3% can be attained for human consumption (Misachi, 2019) and due to water’s solubility, it is difficult to attain ‘pure water’ as other natural chemicals and microbes can be found in water.
However, with the progression of technology, anthropogenic activity such as mining, industrial and even consumer waste that isn’t properly managed can add to this continuous issue of water contamination. Plumbing infrastructures has changed the way cleandrinkable water can be transported to the public via copper metal pipes. The only downfall to this is theleaching of heavy metals into drinking water that can be toxic when consumed and can adversely affect your health. Even though the Earth naturally contains heavy metals, the start of the industrial revolution altered the quantities of some elements that has radically changed their geochemical cycle and biochemical balance (Singh et al., 2011) and issues such as acid rain which can break down sediments and release heavy metals.
In Australia, the concentrations of Cu2+ (Copper) in drinking water should be 2mg/L (Australian Drinking Water Guidelines 6, 2011). This study explores the efficient extraction of coffee grounds on different copper concentrations in water as continuous exposure to heavy metals to the body will bioaccumulate and disrupt the bodies metabolic activity. Although, copper is an essential mineral in the human body necessary in the aid of making red blood cells and maintaining the immune system and nerve cells (Megan, 2017), but in high amounts, this can be dangerous. Wilsons disease is a rare genetic disorder that is an excess copper stored in body tissues (Brewer et al., 2019) and when more copper is consumed, this can rapidly increase the symptoms associated with this rare disease. An excessive intake of copper can lead to short term and long-term health risks such as nausea, vomiting diarrhea, headaches, weakness and more serious risks such ad cirrhosis and jaundice (Megan, 2017).
RESULTS AND DISCUSSION
The analysis of copper concentrations in the solution after the addition of coffee ground was as we expected. The ‘alizarin red solution was used to react with Cu2+, forming a coloured water-soluble complex’ (2), which meant that the more copper present in the solution, the redder the appearance. To ensure that the results we obtained were reliable, an initial absorbance with no coffee added to the solution was measured so that there was a control to compare our final results to.
The initial absorbance of a 10ppm copper solution ranged between 0.81c to 0.82c. The higher the absorbance, the more copper present which is with the grey line.
Effects of Coffee Grounds
The use of biodegradable products such as coffee grounds to reduce the amount of copper ions present in a solution is an innovative and efficient way of correcting heavy metal leaching in drinking water. There is a linear relationship between the amount of coffee grounds added into the solution and the percentage of copper removed. As the mass of coffee grounds increase the absorption decreases, and the amount of copper present in the solution also has decreased. These results support our hypothesis that an increasing amount of coffee will adsorb more copper ions.
There were a few limitations that we faced in this experiment that would of have reduced how accurate we carried out this task. To weigh the precise amount of coffee grounds, a digital scale was used; however, external factors such as air conditioning in the lab and people leaning against the bench caused fluctuations on the amount of coffee weighed for each test tube. This caused an uncertainty for the amount of coffeegrounds in each tube decreasing the validity. It is recommended for future work to grind coffee grounds which would increase the overall surface area for more copper adsorption (Seniunaite et al. 2014).
Heavy metals are nonbiodegradable; so, to use a product that is biodegradable which can reduce the concentration of copper in fresh water is an environmental and economical approach. In Sydney, the St Mary’s water recycling facility treats 33.5 million litres of water every day through the process of reverse osmosis (Sydney Water, 2019). The cost of manufacturing is not stated online; however, a home system costs $12,000 USD – $18,000 USD installed (Aquatell U.S., 2019). Other water treatments include ultra-filtration, distillation and ion exchange.
Mass of coffee grounds (g) 2019) which cost upwards of millions, or trillions of dollars (Guo et al., 2014). Coffee is accessible to the public and Australian grown coffee beans are retailed for 0.06 cents per gram. This is an economical approach and can be used in conjunction with other wastewater treatments as it does not eradicate copper entirely.
- Aquatell U.S. (2019), How Much Do Whole Home Reverse Osmosis Systems Cost?, Online, 21 Oct. 2019
- Brewer, G., S, M., K, H. and Emeritus, S. (2019). Wilson Disease – NORD (National Organization for Rare Disorders). NORD (National Organization for Rare Disorders), Online, 21 Oct. 2019 < https://rarediseases.org/rare-diseases/wilson-disease/>
- Megan Ware, 2017, Copper: Health benefits, recommended intake, sources, and risks, Health Benefits and risks in copper, Medical News Today, Online, 25 Oct. 2019
- Misachi, J., 2019., What Percentage of the Earth’s Water Is Drinkable? World Atlas, Online, 18 Oct. 2019,
- Seniunaite, J., Vaiskunaite, R., Bolutiene, V., 2014, ‘Coffee grounds as an adsorbent for copper and lead removal form aqueous solutions’ International Conference Environmental Engineering, vol. 9 selected papers.
- Singh, R., Gautam, N., Mishra, A., Gupta, R. 2011, ‘Heavy metals and living systems: An overview’, Indian Journal of Pharmacology, Vol. 43, no. 3, pp.246-253
- Sydney Water, 2019, St Marys Water Recycling Plant, Online, 23 October 2019, CDC (Centre of Disease Control and Prevention), 2019, Copper and Drinking Water from Private
- Wells, Online, 25 October 2019 Guo, T., Englehardt, J., Wu, T., 2014, ‘Review of cost versus scale: Water and wastewater treatment and reuse processes’, Water science and technology: a journal of the International Association on Water Pollution Research., Vol. 69, pp, 223-34
- Grampians Olive Co. (2019). Australian Coffee, Online, 26 October 2019,
- Laskey, J., Sinha, S., 2019, The Health Benefits of Water, Everyday Health, Online, 26th October 2019, , https://www.everydayhealth.com/water-health/water-body-health.aspx>
- Author Year, Title of webpage, Description, Publisher, Place of Publication, viewed date,.(1) https://www.jstage.jst.go.jp/article/analsci/22/4/22_4_617/_pdf