Principles of Scientific Practice Report: Copper Extraction Analysis

This report details an experiment investigating the effectiveness of coffee grounds in extracting copper ions from a solution. The study explores the relationship between copper ion concentration and absorbance, using a spectrophotometer for analysis. The experiment involved preparing solutions with varying copper concentrations and measuring their absorbance. Additionally, the report examines the impact of different concentrations of coffee grounds on copper removal efficiency, demonstrating that increased coffee ground concentration leads to a higher percentage of copper removal. The findings validate existing theories on adsorption and highlight the potential of coffee grounds as a cost-effective adsorbent for heavy metal removal from water. The report includes experimental procedures, results, discussions, and conclusions, along with sources of error and a comprehensive reference list. The results show a clear correlation between copper concentration and absorbance, supporting the use of coffee grounds as a viable method for copper extraction from water.

Science Practice 1
Principles of Scientific Practice
By Name
Class (Course) Name
Professor (Tutor)
School (University) name
The City and State where it is located
The Date

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Abstract
The effect of copper (II) ion concentration on the amount of absorption was determined.
A different solution of copper II ions blank (0.5, 1, 2, 5, 10 ppm) were prepared absorbance of
the solution recorded in excel spreadsheet. The result showed that absorbance increases with
increase in concentration, thus validating the existing theories. In addition, the experimental also
sought to study the process of copper extraction using coffee grounds. Copper was extracted
from its solution using the coffee ground. The concentration of coffee ground was varied (0.1g,
0.2g, and 0.3g) to determine the percentage of removal of copper by the coffee ground. The
result shows that the percent removal rate of 0.3g of coffee grounds was about 67.02% while that
of 0.1g of coffee was 47%. This shows that the higher the concentration of coffee ground the
increased copper extraction
Keywords: absorption, concentration, coffee grounds, adsorption, heavy metals

Science Practice 3
Introduction
Heavy metal
When heavy metals dissolve in surface water it pose a serious health risk to the
population. Large number of industries including those manufacturing pigments and paints,
battery manufacturing, mining operation, metal plating, glass and ceramic industries usually
produce waste waters heavily polluted with these heavy metals (Gupta et al., 2018). When this
water is discharge to streams and rivers, they pose a great danger to both animals and people
relying on these waters for their livelihood (Gupta et al., 2018). Most industrial wastewaters
have either lead, cyanide, mercury, chromium, nickel, zinc, and Copper dissolve in it. When
people consume such waters, they end up developing many health complications. These metals
will find their way in human body in form of dissolved ions and will gradually accumulate in the
body to a level that can cause serious ill health to the victim (Arvanitoyannis, 2016).
Copper: It is a transition metal belonging to group IB and period 4 of the periodic table.
Copper has a density of 8.96g/cm3, atomic mass of 63.5, atomic number of 29, boiling point of
2595 °C and melting point of 1083 °C (Harvey, 2015). Cu2+¿ ¿ is often found in several sources
of wastewater such as copper polishing, wire drawing, manufacturing of paint, manufacturing if
printed circuit board, printing operations, wood preservative, and electro plating (Valcarcel,
2014). The concentration of copper often vary based on the type of wastewater. Copper as an
essential trace element, it plays a key role in both animal and plant growth. Small amount of
Cu2+¿ ¿ can be used in farming to provide healthy plants and animals (Harvey, 2015). Small
amount of copper ions are needed by the body for a healthy growth and living. Copper ions is
needed in hemoglobin production by the human body. However, when copper concentration in

Science Practice 4
the body is extremely high it results in a medical condition that resembles flu. Based on medical
studies, consumption of water with a high level of copper ion that is above 30g is fatal.
Concentration of copper ion to 1.3mg/l can cause nausea, abdominal pain, and diarrhea. Just like
other heavy metals, copper ion pollutes the environment and should be prevented from reaching
the natural habitat.
Adsorption
Many methods can be used to remove metals from water solution. This include
precipitation, evaporation, electro coagulation, chemical precipitation, ion exchange on resins,
solvent extraction as well as cementing and separation through membrane. However, nearly all
these methods are costly (Beran, 2014). One of the latest method of removal of metals from
water solution and that has been proven cost effective is adsorption method. Adsorption is basic
procedure during the physiochemical treatment of solutions that are polluted. Adsorption is
basically a process of separation where certain components of the liquid phase are basically
transferred to the solid adsorbents surface (Djati, 2015). Exposing the surface of a solid to a fluid
phase, most of the fluid phase molecules tends to concentrate or collects at the solid surface. The
difference in polarity, shape or molecular mass makes the separation possible by causing the
surface to hold more strongly some molecules that other molecules or pores are too minute to
allow larger molecules. The operation of adsorption can be semi-batch, batch. When small
portion require treatment then continuous batch operation is applicable. The distribution of the
equilibrium is based on time of contact in batch operation (Crowe & Bradshaw, 2014).
Coffee grounds

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Huge amount of coffee beans are normally processed annually and used to make coffee
drinks around the globe. But about 50 percent of the total processed coffee beans are disposed as
used coffee grounds. Scientists of late have explored the use of renewable resources as effective
adsorbents for removal or extraction heavy metals from water. Used coffee grounds consist of
hemicellulose, lignin, pectin, cellulose, as well as small quantity of extractives. The most
abundant functional groups including carboxyl group, amino group, and hydroxyl group on the
used surface of grounds makes it one of the most cheapest and safest method of extracting
pollutants majorly heavy metals (copper) from water (Hunt, Block & McKelvy, 2015)
Coffee grounds have been shown to be great adsorbent especially for heavy metal from
aqueous solutions. Increased in the concentration of coffee grounds have been shown to increase
its percentage efficiency of removal (Harvey, 2015).
Objective
The subjective of the experiment was to determine how concentration coffee grounds
influence its percentage removal of copper.
Procedure
Six, 25 mL sample vials were used for the collection of the concentrations. Each vial was
labeled with concentration (blank, 0.5, 1, 2, 5, 10 ppm). 10 mL of each Cu2+¿ ¿ was poured into
the five of the 25 mL sample vials. Deionized water then added to the vial labeled blank. A
buffer solution of sodium acetate of 5 mL was then added to each sample vial and Alizarin, of 5
mL each added to every 24 mL sample vials (Lab Report Manual, 2019). The vials were then
swirled to mix the content. The retrieval of a cuvette was performed for all the experiment and
measurement done. The rinsing of the cuvette was performed two-three times before the sample
solution being placed to the line mark. The cuvette was then placed in the spectrophotometer.

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The striped side of the spectrophotometer faced the experimenter (Lab Report Manual, 2019).
The measurement was taken after the reading had stabilized and the results recorded in excel.
The rinsing of the cuvette was performed using the next solution sample to be determined and
this was done two times. The same procedure was followed for the remaining samples and
results recorded (Lab Report Manual, 2019).
Extraction of Cu2+¿ ¿using coffee grounds
3, 50mL centrifuge tubes were used for the experiment. 30 mL of the sample solution
was poured into a centrifuge tube (Lab Report Manual, 2019). Each centrifuge tube had a sample
of different concentration. A buffer solution of sodium acetate was then added into each
centrifuge tube. Vortex mixture was used to carry the mixing in each centrifuge tube. Each
mixed solution of 10 mL was transferred to sample vials of 25 mL. Alizarin solution then added
to each sample vials. The solution was then poured into coveter and the spectrophotometer used
to find the value, which was then tabulated in excel sheet. The process was repeated twice and
the remaining solution used as control (Lab Report Manual, 2019).
The solutions were then poured into six, centrifuge tubes. Alizarin red was not added to
10 mL solutions. Three centrifuge tubes were labeled and 0.1, 0.2 and 0.3 g of ground coffee
added on three tubes. Each tube was stirred for 10 seconds and the solutions allowed settling for
ten minutes. The centrifuge tubes were centrifuged at 2000 rpm for 5-minutes (Lab Report
Manual, 2019). The solution was the pippete into a 25 mL vial with a high level of consistency
being observed. 5 mL alizarin Red was added to each vial. Absorbance was measured for each
solution and results recorded in the datasheet on UTSOnline (Lab Report Manual, 2019).

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Results Presentation
0 2 4 6 8 10 12
0
0.2
0.4
0.6
0.8
1
1.2
f(x) = 0.056916714095997 x + 0.420951242648454
R² = 0.998455544066719
Carlibration Curve
Concentration (ppm)
Absorbance
Fig 2
0.05 0.1 0.15 0.2 0.25 0.3 0.35
0
10
20
30
40
50
60
70
80
R² = 0.964154934112284
Effect of coffee amount on copper ion
removal
Coffee amount (g)
%removed average
Fig 3.

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Discussion
As in fig (2) above, the best line of fit is explained by the equation y=0.0569 x +0.421
with linearity value R2=0.9885. since the linearity value is close to 1, this proves the reliability
of the results. As observed in fig 1, the increase in the concentration of copper ions increases its
absorbance rates. At 0 concentration is evident that the absorbance was about 0.4 and the value
linearly increased with increased in concentration of up to 1 when the concentration was 10ppm .
According to Beer’s law absorbance is directly proportional to concentration and thus the
equation y=0.0569 x +0.421 can be used to estimate the concentration of the unknown solution
(Martell & Hancock, 2015). During the experiment color changed from yellowish to dark red.
The concentration of copper hence can be calculated as:
( Absorbance−0.421)/0.0569
In fig 3, the amount of coffee grounds concentration increases the removal of the copper
II ions. The hypothesis theory was proven. When the number of coffee grounds is increased, the
removal percentages also increases. When 0.1g of the coffee ground is added, the average
percentage removal was about 47%, then when 0.2 g of coffee grounds, the average removal was
53.7%, and when it was 0.3 the percentage removal rate rose to 67.02%. There is a large
difference between the average % removal at 0.1g and 0.3 and hence it can be concluded that the
increase in the coffee ground increases absorbance.
The adsorption of copper by adsorbent takes place in different sites based on the types of
sites functional groups (Lewinsky, 2016; Lichtfouse, Robert & Schwarzbauer, 2018). Hence,
removal of copper by adsorbent is influenced by a number of factors including the dose of

Science Practice 9
adsorbent, type of metal, as well as pH, ionic strength, initial concentration of the metal, of the
adsorbent to bind the metal is based on the functional group and their affinity to bind to a
specific metal (Anantha & Kota, 2016; Arvanitoyannis, 2016; Djati, 2015). Coffee grounds have
shown to be a good adsorbent for copper removal and it seems there are good binding sites in the
coffee grounds for copper removal.
Conclusion
The coffee ground has proven to be a good adsorbent for the removal of copper from a
solution. Alternatively, an increase in copper concentration increases its absorbance. However,
the removal capacity of an adsorbent depends on a number of factor including the concentration
of adsorbent, pH, among other factors. The objectives of the experiment were accomplished
since the findings of the results were the same as the existing literature and scientific evidence of
the hypothesis under tests.
Sources of error
The sources of error included error in taking the readings and spilling of the solution
during the transfer of the solutions. Some traces of coffee could have also entered the pipette
solution and this influenced the results.

Science Practice 10
Reference List
Anantha, R. K., & Kota, S. (2016). An evaluation of the major factors influencing the removal of
copper ions using the eggshell (Dromaius novaehollandiae): chitosan (Agaricus bisporus)
composite. 3
Biotech, 6(1), 83. doi:10.1007/s13205-016-0381-2
Arvanitoyannis, I. (2015). Waste management for the food industries. Amsterdam : Academic
Press.
Beran, J. A. (2014). Laboratory manual for principles of general chemistry. Hoboken (N.J.) :
Wiley.
Crowe, J., & Bradshaw, T. (2014). Chemistry for the biosciences: The essential concepts.
Oxford: Oxford University Press.
Djati, U. H. (2015). The adsorption of heavy metals by waste tea and coffee residues: From
science to potential environmental applications. Saarbrucken: LAP Lambert Academic
Pub.
Gupta, T., Agarwal, A. K., Agarwal, R. A., & Labhsetwar, N. K. (2018). Environmental
contaminants: Measurement, modelling and control. Singapore: Springer.
Harvey, D. (2015). Modern analytical chemistry. Boston: McGraw-Hill.
Hunt, H. R., Block, T. F., & McKelvy, G. M. (2015). Laboratory experiments for general
chemistry. Australia: Brooks/Cole-Thomson Learning.

Science Practice 11
Lab Report Manual (2019). 60001 Principles of Scientific Practice Practical 2 – Lab Skills and
Data Analysis.
Lewinsky, A. A. (2016). Hazardous materials and wastewater: Treatment, removal and
analysis. New York, NY: Nova Science Publishers.
Lichtfouse, E., Robert, D., & Schwarzbauer, J. (2015). Environmental Chemistry: Green
Chemistry and Pollutants in Ecosystems. Berlin, Heidelberg : Springer-Verlag Berlin
Heidelberg,
Martell, A. E., & Hancock, R. D. (2015). Metal Complexes in Aqueous Solutions. Boston, MA:
Springer US.
Valcarcel, C. M. (2014). Principles of Analytical Chemistry: A Textbook. Berlin, Heidelberg: Springer
Berlin Heidelberg.