The Use of Synthetic Zeolite Adsorbents from Rice Husk Ash and Bentonite

Oct 13, 2025 by wbrum.org 24 views

Introduction

The rapid population growth in Indonesia, particularly in big cities, has led to an increased demand for housing and clean water. Unfortunately, groundwater in some areas is often contaminated with heavy metals, including Manganese (Mn). Water with excessive Mn content causes the color of water to change (brown/purple/black) and becomes murky, making it necessary to further process it for domestic purposes. The use of surface water also increases in society, but technology to eliminate metal content is still needed to ensure water safety.

The Problem of Manganese (Mn) in Water

Manganese is a naturally occurring element that can be found in small amounts in water. However, excessive levels of Mn can cause a range of health problems, including neurological damage, reproductive issues, and even cancer. In addition to health concerns, Mn can also cause aesthetic problems, such as discoloration and turbidity, making it difficult to use water for drinking, cooking, and other household purposes.

Adsorption as a Solution

Adsorption is a process that uses a solid material, known as an adsorbent, to remove impurities from a liquid or gas. In the case of Mn removal, zeolite and bentonite are two common adsorbents that have been shown to be effective in removing Mn from water. Zeolite is a type of mineral that has a high surface area and can attract and hold onto Mn ions, while bentonite is a type of clay that can also adsorb Mn ions.

The Use of Synthetic Zeolite Adsorbents from Rice Husk Ash and Bentonite

This study aims to remove Mn metal (Mn) from artificial groundwater in adsorption conditions using a batch method and continuous column with a mixture of synthetic zeolite adsorbents from rice husk ash and bentonite activated sulfuric acid. The study examines the effect of variations in the Zeolite-Bentonite mixture ratio and contact time during the adsorption process.

Methodology

The batch method uses 200 ml of artificial groundwater which is adsorbed with a mixture of zeolite-bentonite adsorbents with a ratio of 1: 1, 1: 2, and 1: 3, as well as contact time 5, 10, 15, 30, 45, 60, 90, 120, 120, 120, 150, and 180 minutes, with stirring speeds 0, 50, 100, and 150 rpm. While the continuous column method is carried out by flowing 1000 ml of artificial groundwater in a column with a height of 5 cm and an adsorbent mass of 5 grams, and contact time 15, 30, 45, 60, 120, 180, 240, and 300 minutes.

Results

The results of the SEM-EDS analysis show that the surface of Zeolite-Bentonite activated H2SO4 becomes rough and is formed many cracks, which indicates an increase in surface area due to activation. From the Batch Method research, the best zeolite-bentonite mixture ratio is 1: 3 with a contact time of 120 minutes and stirring speed of 150 rpm. In this condition, the Mn content reaches 0.3569 mg/L with a percentage reduction of 85.60%. This shows that the number of bentonite is more than zeolite gives optimal results.

In the continuous column method, the best zeolite-bentonite ratio is 1: 3 with a contact time of 15 minutes. In this condition, the Mn content reaches 0.0097 mg/L, the largest adsorption capacity is 0.4903 mg/g, and the lowest CT/CO ratio value is 0.0194 mg/ml. This means that the longest saturation time is achieved in the condition and mixture of the adsorbent.

Kinetics Model

The kinetics model chosen for zeolite-bentonite adsorbents in the batch method with a ratio of 1: 3 for Mn reduction is the second order pseudo with a value of R2 0.9993. Meanwhile, in the continuous column method, Thomas's kinetics model was selected with a value of R2 0.9087.

Conclusion

Overall, the results of the study prove that the use of synthetic zeolite adsorbent mixtures of rice husk ash and bentonite is activated by sulfuric acid by batch method and column has the potential to remove metals from ground water.

The Importance of This Research

This study is very relevant because it provides an alternative solution to overcome the problem of Mn metal pollution in ground water and surface water. The use of zeolite-bentonite adsorbents that are easily obtained and environmentally friendly, as well as efficient methods, can be an effective solution to produce clean water that is safe for the community.

Advantages of Zeolite-Bentonite Adsorbent

Availability: Zeolite and bentonite are easily found in Indonesia, thus minimizing import costs.
Environmentally friendly: This adsorbent comes from renewable natural resources, so that it does not have a negative impact on the environment.
Efficiency: The adsorption process with zeolite-bentonite is relatively easy and efficient, so that it can be applied widely on an industrial scale.

Development Potential

This research can be developed further by:

Assessing the effect of other factors such as pH and temperature on the adsorption process.
Developing an adsorbent regeneration method so that it can be reused.
Applying Zeolite-Bentonite adsorption technology on an industrial scale to produce clean water.

This research provides an important contribution in the development of safe and sustainable clean water treatment technology. Thus, this research has the potential to improve the quality of life of the community and support sustainable development in Indonesia.

Frequently Asked Questions

We have received many questions from readers about our research on making adsorbents using a mixture of bentonite soil activated by sulfuric acid and synthetic zeolite from rice husk ash to reduce manganese levels (Mn) in water. Here are some of the most frequently asked questions and our answers:

Q: What is the purpose of this research?

A: The purpose of this research is to develop a cost-effective and environmentally friendly method for removing manganese (Mn) from water using a mixture of bentonite soil activated by sulfuric acid and synthetic zeolite from rice husk ash.

Q: What are the benefits of using this method?

A: The benefits of using this method include:

Cost-effectiveness: The materials used in this method are readily available and inexpensive.
Environmental friendliness: The method is environmentally friendly and does not produce any hazardous waste.
Efficiency: The method is efficient and can remove high levels of manganese from water.

Q: How does the method work?

A: The method works by using a mixture of bentonite soil activated by sulfuric acid and synthetic zeolite from rice husk ash to adsorb manganese ions from water. The adsorbent is then separated from the water, and the manganese ions are removed.

Q: What are the advantages of using zeolite-bentonite adsorbents?

A: The advantages of using zeolite-bentonite adsorbents include:

Availability: Zeolite and bentonite are easily found in Indonesia, thus minimizing import costs.
Environmentally friendly: This adsorbent comes from renewable natural resources, so that it does not have a negative impact on the environment.
Efficiency: The adsorption process with zeolite-bentonite is relatively easy and efficient, so that it can be applied widely on an industrial scale.

Q: Can this method be used to remove other heavy metals from water?

A: Yes, this method can be used to remove other heavy metals from water, including lead, mercury, and arsenic.

Q: How can this method be scaled up for industrial use?

A: This method can be scaled up for industrial use by increasing the size of the adsorbent and the flow rate of the water. Additionally, the method can be optimized for specific industrial applications by adjusting the ratio of zeolite to bentonite and the activation method.

Q: What are the potential applications of this method?

A: The potential applications of this method include:

Drinking water treatment: This method can be used to remove manganese and other heavy metals from drinking water, making it safe for human consumption.
Industrial water treatment: This method can be used to remove manganese and other heavy metals from industrial wastewater, reducing the environmental impact of industrial processes.
Agricultural water treatment: This method can be used to remove manganese and other heavy metals from agricultural water, reducing the risk of contamination of crops and soil.

Q: What are the future directions of this research?

A: The future directions of this research include:

Optimizing the method for specific industrial applications: This method can be optimized for specific industrial applications by adjusting the ratio of zeolite to bentonite and the activation method.
Scaling up the method for industrial use: This method can be scaled up for industrial use by increasing the size of the adsorbent and the flow rate of the water.
Developing new adsorbents: New adsorbents can be developed using different materials and activation methods to improve the efficiency and effectiveness of the method.