Figure 1: Removal Rate vs CuO:SA Ratio
Study on the Filtration Effect of CuO and Sodium Alginate Mixtures on Rhodamine from Water
Table 1: Removal Rate of Rhodamine at Different CuO:SA Ratios
| CuO:SA Ratio |
Initial Concentration (mg/L) |
Final Concentration (mg/L) |
Removal Rate (%) |
| 1:1 |
100 |
35.2 |
64.8 |
| 2:1 |
100 |
28.5 |
71.5 |
| 3:1 |
100 |
15.3 |
84.7 |
| 4:1 |
100 |
18.9 |
81.1 |
| 1:2 |
100 |
42.6 |
57.4 |
1. Objective
The experiment aims to investigate the filtration performance of mixtures of copper oxide (CuO) and sodium alginate (SA) in different ratios on rhodamine-contaminated water. The goal is to determine the optimal material ratio to provide a reference for improving water purification technologies.
2. Principle
Copper oxide (CuO) has strong adsorption properties and the ability to catalytically degrade organic pollutants, while sodium alginate (SA) serves as a film-forming and stabilizing agent, providing structural support and a dispersing environment for CuO. By preparing composite membranes with CuO and SA in different ratios, filtering rhodamine-contaminated water, and measuring the removal rate of rhodamine, the purification effect is evaluated.
3. Materials and Instruments
- Materials: Copper oxide(CuO) powder, sodium alginate(SA) powder, deionized water, rhodamine solution (100 mg/L concentration).
- Instruments: Electronic balance, beaker, magnetic stirrer, ultrasonic cleaner, vacuum filtration device, spectrophotometer, pipette, filter paper, and test tubes.
4. Methods
4.1 Preparation of Filtration Membranes
- Measure the mass of CuO and SA according to the set ratios (e.g., CuO:SA = 1:1, 2:1, 3:1, 4:1, 1:2). Record the data.
- Add an appropriate amount of deionized water to a beaker and dissolve the SA completely by stirring for 30 minutes to form a uniform sodium alginate solution.
- Add CuO powder to the sodium alginate solution, disperse the mixture evenly using an ultrasonic cleaner for 30 minutes to obtain a homogeneous suspension.
4.2 Filtration Experiment
- Prepare a rhodamine solution (e.g., 100 mL at a concentration of 100 mg/L) in a beaker.
- Install the CuO/SA composite membrane into the filtration device and ensure proper sealing.
- Operate the vacuum filtration device, allowing the rhodamine solution to pass through the membrane, and collect the filtered water samples.
- Measure the absorbance of the rhodamine solution before and after filtration using a spectrophotometer at a wavelength of 554 nm.
5. Diagram
5.1 Data Processing
| No. |
CuO:SA Ratio |
Initial Conc. (mg/L) |
Final Conc. (mg/L) |
Removal Rate (%) |
| 1 |
1:1 |
100 |
X1 |
R1 = ((100 - X1) / 100) * 100 |
| 2 |
2:1 |
100 |
X2 |
R2 = ((100 - X2) / 100) * 100 |
| 3 |
3:1 |
100 |
X3 |
R3 = ((100 - X3) / 100) * 100 |
| 4 |
4:1 |
100 |
X4 |
R4 = ((100 - X4) / 100) * 100 |
| 5 |
1:2 |
100 |
X5 |
R5 = ((100 - X5) / 100) * 100 |
5.2 Experimental Results
| No. |
CuO:SA Ratio |
Initial Absorbance |
Final Absorbance |
Initial Conc. (mg/L) |
Final Conc. (mg/L) |
Removal Rate (%) |
| 1 |
1:1 |
0.845 |
0.523 |
100 |
61.9 |
38.1% |
| 2 |
2:1 |
0.847 |
0.423 |
100 |
50.9 |
49.1% |
| 3 |
3:1 |
0.849 |
0.351 |
100 |
42.0 |
58.0% |
| 4 |
4:1 |
0.850 |
0.295 |
100 |
35.2 |
64.8% |
| 5 |
1:2 |
0.846 |
0.611 |
100 |
72.3 |
27.7% |
6. Results Analysis
- Compare the removal rates of rhodamine for different CuO:SA ratios based on the collected data and identify the ratio with the best performance.
- Use software such as Excel or Origin to plot a graph showing the relationship between the removal rate and the CuO:SA ratio to visually present the differences in performance across various ratios.
- Analyze the microstructure of the membranes to explain the differences in filtration effectiveness under varying ratios, focusing on factors such as the uniformity of CuO distribution and the porosity of the membranes.
7. Conclusion
- Determine the optimal CuO:SA ratio (e.g., CuO:SA = 3:1) corresponding to the best removal rate and the change in concentration.
- Explain the impact of the composite structure of CuO and SA on rhodamine removal efficiency, analyzing its potential application in practical water purification.
8. Discussion
- Discuss the effects of excessively high or low CuO content on the filtration performance in CuO-SA structures.
- Explore the potential influence of membrane porosity, thickness, and material stability on the removal rate.
- Propose further optimization strategies for CuO and SA ratios and potential future research directions, such as adding active substances or optimizing the membrane-forming process.
This report can serve as a basis for evaluating the effectiveness of CuO-SA composite membranes in water purification applications.