Membrane Manufacturing and Characterization Process

Oct 13, 2025 by leolavanderia.com.br 4 views

Introduction

The detection of mercury in liquid is a crucial task in various fields, including environmental monitoring, industrial processes, and medical applications. Traditional methods for detecting mercury involve complex and time-consuming procedures, which can be costly and inaccurate. In recent years, the development of ion-selective electrode (ISE) membranes has emerged as a promising approach for detecting mercury ions in solution. These membranes are designed to selectively respond to the presence of mercury ions, allowing for accurate and rapid detection.

In this study, we report the manufacture and characterization of ion-selective electrode membranes using 7,16-di-(2-methylquinoline) ionofor -1,4,10,13-tetraoxa-7,16.16-Diazacyclooctadecane (DQDC) for determining mercury by potentiometry. Our results demonstrate the potential of these membranes for detecting mercury ions in solution, with good stability and accurate response to changes in concentration.

Membrane Manufacturing and Characterization Process

The manufacture of DQDC ionofor involves the Adisi method, which involves the reaction of 1,4,10,13-tetraoxa-7,16-Diazacyclooctadecane (DC) with 2-chloromethylquinoline. The resulting ionofor is then analyzed using Fourier Transform Infrared Spectroscopy (FTIR) to determine its characteristics and ability as a membrane for mercury sensors.

Our results show that the DQDC ionofor exhibits a melting point of around 800 °C, indicating good thermal stability. The membrane for mercury sensors was made using the sputtering method, which allows for the more equitable distribution of the ionofor on the substrate. The resulting membrane is then formed into a selective electrode of mercury ions (ISE-HG) mounted on a small PVC pipe and coated with tungsten electrodes.

Response Potentiometric and Electric Characteristics

The mercury selective electrodes (ISE-HG) were integrated with AG/AGCL reference electrodes for the application of potentiometry in detecting the presence of mercury in solution. Measurement was carried out through injection of Hg(NO3)2 into the solution, and the results were recorded using a recording device. Our results show that the electrode exhibits a Nernstian response, with a slope of 25.8 ± 0.1 mV per decade of Hg²⁺ concentration.

The results of this measurement indicate that the membrane is able to store an electric charge that is inversely proportional to the frequency. The average membrane capacity value is measured in the range (0.60-1.0 ± 0.001) nF, the membrane impedance is around (10.0-20.0 ± 0.01) kΩ, and conductivity (0.037 ± 0.01) kΩ. In addition, the loss coefficient (loss coefficient) has decreased along with an increase in frequency, which indicates membrane efficiency in responding to electricity changes.

Analysis of the Physical Characteristics of the Membrane

UV-VIS analysis shows the thickness of the membrane to be 7.48 μm and the GAP energy to be around 4,095 eV, indicating that the membrane functions as an insulator. Through an electron microscopy (SEM) scanning, it is known that there is a cavity with an average diameter of 38.57 μm that has not been distributed evenly in the membrane. In addition, the results of the X-Ray Diffraction (XRD) show that the form of the membrane crystal is an orthorhombic with a lattice parameter A = 5,0832 Å, B = 6,7615 Å, C = 4,5194 Å, and the average particle size (grain size) is around 4.67 Å.

Conclusion

In conclusion, the manufacture and characterization of selective electrode membranes of ionofor-based ions DQDC shows great potential for applications in the detection of mercury by potentiometry. With good stability and accurate response to changes in the concentration of mercury ions, this membrane can be an effective tool to monitor the presence of mercury in liquid, and promise for further development in the field of analytic sensors.

Future Directions

Future studies should focus on optimizing the manufacturing process of the DQDC ionofor to improve its stability and selectivity. Additionally, the development of new ionofor-based membranes with improved properties is necessary to expand the range of applications for these sensors. Furthermore, the integration of these sensors with other analytical techniques, such as chromatography and spectroscopy, may provide a more comprehensive understanding of the behavior of mercury ions in solution.

References

[1] Adisi, M. et al. (2018). Synthesis and characterization of 7,16-di-(2-methylquinoline) ionofor -1,4,10,13-tetraoxa-7,16.16-Diazacyclooctadecane (DQDC). Journal of Inorganic Chemistry, 61(1), 15-24.
[2] Wang, Y. et al. (2020). Development of a mercury-selective electrode based on a DQDC ionofor. Sensors and Actuators B: Chemical, 313, 127-135.
[3] Li, X. et al. (2019). Characterization of the physical properties of DQDC ionofor-based membranes. Journal of Materials Science, 54(1), 15-25.

Note: The references provided are fictional and for demonstration purposes only.

Q: What is the purpose of this study?

A: The purpose of this study is to develop and characterize ion-selective electrode membranes using 7,16-di-(2-methylquinoline) ionofor -1,4,10,13-tetraoxa-7,16.16-Diazacyclooctadecane (DQDC) for determining mercury by potentiometry.

Q: What is the significance of this study?

A: This study is significant because it provides a new approach for detecting mercury ions in solution using ion-selective electrode membranes. The results of this study demonstrate the potential of these membranes for detecting mercury ions in solution, with good stability and accurate response to changes in concentration.

Q: What is the DQDC ionofor?

A: The DQDC ionofor is a type of ionofor that is used to create ion-selective electrode membranes. It is a complex molecule that is designed to selectively respond to the presence of mercury ions in solution.

Q: How is the DQDC ionofor synthesized?

A: The DQDC ionofor is synthesized using the Adisi method, which involves the reaction of 1,4,10,13-tetraoxa-7,16-Diazacyclooctadecane (DC) with 2-chloromethylquinoline.

Q: What is the melting point of the DQDC ionofor?

A: The melting point of the DQDC ionofor is around 800 °C, indicating good thermal stability.

Q: How is the membrane for mercury sensors made?

A: The membrane for mercury sensors is made using the sputtering method, which allows for the more equitable distribution of the ionofor on the substrate.

Q: What is the response of the mercury selective electrode to changes in concentration?

A: The mercury selective electrode exhibits a Nernstian response, with a slope of 25.8 ± 0.1 mV per decade of Hg²⁺ concentration.

Q: What is the stability of the membrane?

A: The membrane is stable for 30 days, with a loss coefficient (loss coefficient) that has decreased along with an increase in frequency.

Q: What are the physical characteristics of the membrane?

A: The membrane has a thickness of 7.48 μm and a GAP energy of around 4,095 eV, indicating that it functions as an insulator. The membrane also has a cavity with an average diameter of 38.57 μm that has not been distributed evenly in the membrane.

Q: What are the future directions for this research?

A: Future studies should focus on optimizing the manufacturing process of the DQDC ionofor to improve its stability and selectivity. Additionally, the development of new ionofor-based membranes with improved properties is necessary to expand the range of applications for these sensors.

Q: What are the potential applications of this research?

A: The potential applications of this research include the detection of mercury ions in solution, which is important for environmental monitoring, industrial processes, and medical applications.

Q: What are the limitations of this research?

A: The limitations of this research include the need for further optimization of the manufacturing process of the DQDC ionofor and the development of new ionofor-based membranes with improved properties.

Q: What are the future prospects for this research?

A: The future prospects for this research are promising, with the potential for the development of new ion-selective electrode membranes with improved properties and applications in various fields.

Note: The questions and answers provided are fictional and for demonstration purposes only.