Vol.
16 No.
Jurnal Riset Teknologi Pencegahan Pencemaran Industri Journal homepage: https://w.
Analysis of Neutron Radiation Absorption Capacity of Coir Fiber Composite Board as A Neutron Radiation Shield Evi Christiani Sitepu1.
Dimas Frananta Simatupang2 1Mechanical Engineering Study Program.
Politeknik Teknologi Kimia Industri Medan.
North Sumatera.
Indonesia 2Chemical Engineering Study Program.
Politeknik Teknologi Kimia Industri Medan.
North Sumatera.
Indonesia
A R T IC L E I N F O
Article history:
Received: January, 22 2025 Received in revised form: April 20 2025 Accepted: April 29 2025 Available online: May 15 2025 Keywords:
Linear Attenuation Coefficient Absorption Capacity Neutron Radiation ABSTRACT Research has been conducted on the radiation shielding capability of coir fiber composite boards to determine the extent of neutron radiation absorption as it passes through the created radiation shield.
This study aims to ascertain whether coir fiber can be used as a filler in the production of radiation shields.
Initial analysis was conducted using SEM-EDX.
FTIR, and XRD testing.
The results indicated that the primary component of coir fiber is carbon at 68%, which is structured in chemical bonds of cellulose, hemicellulose, and lignin.
Additionally, coir fiber retains a crystalline region observed at the peak of 2=22.
4A, with a crystallinity degree of 35.
46%, suggesting its potential for neutron radiation absorption.
After fabricating the composite board, it was tested using the Neutron Activation Analysis method to evaluate its neutron radiation absorption capability.
The analysis results showed that the absorption capacity of the composite board at a fiber mass fraction of 2.
0 g ranged from 59.
0 g from 64.
3 to 98.
and at 4.
0 g from 73.
5 to 99.
The linear attenuation coefficients (AA) for each coir fiber fraction were found to be 3.
80 cm-1, with half-value layers of 0.
14 cm, respectively, demonstrating that coir fiber can be utilized as a filler for neutron radiation shielding.
The results of this study can add new information regarding the development of radiation protection systems with new materials that can minimize the body's exposure to ionizing radiation in the future.
INTRODUCTION
The development of nuclear radiation applications has been continuously evolving year by year, extending into various industrial sectors such as medicine, agriculture, geophysics, and scientific research, thereby necessitating a deeper study of radiation shielding (Tyagi.
Singhal.
Routroy.
Bhunia, & Lahoti, 2.
Given the role of nuclear utilization, the advancement of radiation protection systems is crucial, with one significant area of research being radiation shields.
Radiation shields are tools or materials designed to protect individuals and equipment from the effects of radiation.
Their primary purpose is to minimize the absorption of ionizing radiation by the body and the associated effects.
Based on the potential effects of radiation, nuclear radiation protection is deemed vital for user safety (Chen.
Bourham, & Rabiei, 2015.
Erdem.
Baykara.
Doyru, & Kuluyztyrk, 2.
Traditionally, materials such as lead, iron, graphite, polyethylene, and concrete have been widely used as shields against nuclear radiation (Abdullah et al.
Shams.
Eftekhar, & Shirani, 2.
Among these, concrete is commonly employed for nuclear radiation shielding (Kharita.
Takeyeddin.
Alnassar, & Yousef, 2008.
Zarvianti.
Fitriyani.
Surya Bery.
Khalid Rivai, & Sulistioso, *Correspondence author.
E-mail: evisitepu@kemenperin.
id (Evi Christiani Sitep.
doi: https://10.
21771/jrtppi.
2503-5010/2087-0965A 2024 Jurnal Riset Teknologi Pencegahan Pencemaran Industri-BBSPJPPI (JRTPPI-BBSPJPPI).
This is an open acces article under the CC BY-NC-SA license .
ttps://creativecommons.
org/licenses/by-nc-sa/4.
0/).
Accreditation number: (Ristekdikt.
158/E/KPT/2021 Sitepu et.
/ Jurnal Riset Teknologi Pencegahan Pencemaran Industri Vol 16 No 1 .
1-8 2.
because it effectively reduces the intensity of radiation, particularly gamma radiation, which has strong penetration capabilities (Naikwadi.
Sharma.
Bhatt, & Mahanwar, 2.
Additionally, concrete can also serve as a shield against fast neutron radiation (Adeli.
Shirmardi, & Ahmadi, 2.
Some studies even suggest that various types of concrete mixtures are suitable and potentially effective as radiation shields (El-Samrah.
Abdel-Rahman, & El Shazly, 2018.
Papachristoforou & Papayianni, 2.
Concrete is considered highly ideal for shielding against gamma rays or neutrons (Azreen.
Rashid.
Haniza.
Voo, & Mugahed Amran, 2.
However, the use of concrete as a nuclear radiation shield has drawbacks such as its large dimensions and density exceeding 2600 kg/mA, making it relatively expensive to implement (More.
Alsayed.
Badawi.
Thabet, & Pawar, 2.
This situation highlights the need to investigate other more efficient materials that can be used as nuclear radiation shields due to the increasing application of nuclear radiation.
Research published by Gosset.
Herter, & Motte .
indicates that materials with low atomic number contents such as boron, carbon, and hydrogen possess the ability to absorb radiation, especially neutrons.
This presents a unique challenge in developing new materials for radiation protection.
Indonesia has a wealth of natural materials that are potential candidates for radiation shielding, such as palm oil shells, wood, and natural fibers due to their specific hardness levels.
Research is needed to assess the absorption capacity of these natural materials as radiation shields (Yanyah & Sutanto, 2.
Currently, studies are being conducted using non-toxic, lightweight, and inexpensive natural materials for radiation shielding (AbuAlRoos.
Baharul Amin, & Zainon, 2019.
Kurudirek.
One such natural material is fiber.
Natural fibers are a highly prospective commodity for future development and have been utilized as reinforcement materials in biocomposites to replace synthetic fibers due to their non-abrasiveness, non-toxicity, biodegradability (Rajesh & Pitchaimani, 2.
In this study, coir fiber is used as a filler in composite boards due to its high carbon content, which is believed to enhance its capability to absorb neutron radiation.
Therefore, the purpose of this study is to evaluate the potential of coir fiber as a filler in composite boards that function as a radiation shield, especially against neutron radiation, by examining the characteristics of the material and its neutron absorption METHODS This research was divided into two stages.
The first stage involves the characterization of coir fiber to assess its potential as a filler in neutron radiation shields using methods such as SEM-EDX.
FTIR, and XRD.
The SEMEDX test was conducted to determine the percentage of the main elements constituting the coir fiber, while FTIR provided information related to the chemical bonds within the fiber, and X-ray diffraction (XRD) was used to identify the crystalline regions present in the coir fiber.
The second stage focused on the fabrication of coir fiber composite board samples.
In this phase, the coir fiber intended for use as a filler is first cleaned with distilled water and then soaked in a 0.
5 M NaOH solution for one hour before being air-dried.
After drying, the coir fibers were cut into 10 cm lengths.
They were then immersed in a polyester resin solution mixed with MEKP catalyst and cast into molds with a thickness of 0.
25 cm.
The mixture was compacted and allowed to cure at room temperature for 18 The intensity of the neutron beam transmitted through the test material is determined by the material's attenuation coefficient using Lambert-Beer's law, as expressed in Equation .
I = I0 eOex where I = neutron beam intensity after passing through sample .
/cm-.
I0 =neutron beam intensity before passing through sample .
/cm-.
AA = attenuatuon of neutron .
and x = thickness of material .
From the equation above, the absorption value of the thermal neutron radiation shielding material can be obtained as shown in Equation .
I OeI Absorption capacity = 0 x 100% .
In addition to absorption capacity, a commonly used concept to describe a material's ability to absorb nuclear radiation is the Half Value Layer (HVL).
The HVL is defined as the thickness of an absorbing material required to reduce the radiation intensity by 50% after passing through that material.
The HVL value can be calculated using Equation .
Sitepu et.
/ Jurnal Riset Teknologi Pencegahan Pencemaran Industri Vol 16 No 1 .
yaycOya = ycoycu2
RESULT AND DISCUSSION
Analysis of Energy Dispersive X-ray Spectroscopy (EDX) The SEM-EDX analysis was conducted to determine the elemental composition and atomic percentage of the coir fiber.
The results, as presented in Element .
eV) Mass% Table 1, indicated that the main elements constituting coir fiber are Carbon.
Oxygen.
Sodium.
Silica, and Calcium, with average atomic percentages obtained from three tests as follows: Carbon 70.
Oxygen 28.
Sodium 0.
Silica 0.
15%, and Calcium 0.
The detailed results of the elemental composition are shown in Table 1.
Table 1.
Results of SEM-EDX Analysis Fitting Coefficient : 0.
Error% Atomic% Na K Si K Ca K Total .
eV) .
First test Fitting Coefficient : 0.
Mass% Error% Atomic% Na K Si K Ca K Element Total Element .
Second test Fitting Coefficient : 0.
eV) Mass% Error% Atomic% Sitepu et.
/ Jurnal Riset Teknologi Pencegahan Pencemaran Industri Vol 16 No 1 .
1-8 Na K Si K Ca K Total .
Third test Fourier Transform Infrared Spectroscopy (FTIR) Analysis The FTIR analysis in this study was conducted over a spectral range of 650Ae4000 cm-1 to identify the presence of carbon within the chemical bonds of cellulose, hemicellulose, and lignin, as illustrated in Figure 1.
Figure 1.
FTIR of coir fiber Figure 1 displayed the FTIR analysis results for coir fiber, indicating that the primary components of coir fiber are Carbon.
Hydrogen, and Oxygen, structured in the form of cellulose, hemicellulose, and lignin.
The presence of carbon and hydrogen is considered an initial indication of neutron radiation absorption capability, as reported by Gosset et al .
, highlighting that elements with low atomic numbers such as Carbon and Hydrogen can effectively absorb neutron radiation.
This analysis underscores the potential of coir fiber as a viable material for applications requiring neutron radiation shielding due to its chemical composition.
X-Ray Diffraction (XRD) Analysis The XRD analysis of coir fiber was performed using CuK radiation ( = 1.
5406 yI) over a 2 range of 20A to 80A.
The objective was to determine whether coir fiber possesses a crystalline structure, as natural materials, including natural fibers, typically exhibit amorphous The diffraction pattern of the coir fiber can be observed in Figure 2.
Sitepu et.
/ Jurnal Riset Teknologi Pencegahan Pencemaran Industri Vol 16 No 1 .
1-8 Figure 2.
XRD of coir fiber Based on the analysis presented in Figure 2, it was evident that coir fiber predominantly exhibits an amorphous structure.
however, it still contained regions with crystalline structure, specifically at 2 angles of 22.
At the peak of 22.
4A, the carbon was identified in the form of cellulose, with a crystallinity degree of 35.
This finding aligned with the results reported by Chalid et .
, which indicated a crystallinity degree of 37% for coir fiber at 2 = 22.
The degree of crystallinity suggests that coir fiber could potentially be utilized as a natural fiber filler in the production of composite boards for neutron radiation shielding applications.
Analysis of Neutron Radiation Absorption by Composite Shields The composite boards were designed to assess their effectiveness in neutron radiation shielding.
After irradiation, the boards were chopped to measure the reduction in neutron beam intensity as it passed through varying thicknesses of the coir fiber composite.
The results of this assessment are presented in Table 2.
Table 2.
Data on the Counting of Coir Fiber Boards as Neutron Radiation Shields Thicknesses of the coir fiber composite .
Counting/minute Mass fraction of coir fiber .
The data from the coir fiber composite shielding against neutron radiation can be analyzed in conjunction with Table 2, which illustrated the extent of neutron radiation intensity reduction as shown in Figure 3.
The graph clearly indicated that as the mass fraction and thickness of the coir fiber composite increase, a greater number of neutrons are absorbed.
Sitepu et.
/ Jurnal Riset Teknologi Pencegahan Pencemaran Industri Vol 16 No 1 .
1-8 reduction in neutron intensity after passing through the coir fiber composite.
This suggested that coir fiber possesses inherent capabilities for neutron radiation absorption.
To determine the absorption capacity of coir fiber composite boards for neutron radiation, the attenuation of neutrons is analyzed.
When neutrons interact with a material, the radiation is not entirely absorbed.
instead, it experiences attenuation or a reduction in intensity.
In other words, attenuation refers to the weakening of radiation intensity after passing through a material.
The data clearly showed that the absorption capacity of the composite board increases with the addition of coir fiber, as depicted in Figure 4.
This highlights the positive impact of incorporating coir fiber on the shielding effectiveness against neutron radiation.
Figure 3.
Neutron Radiation Absorption Capacity of Coir Fiber Composite Figure 3 demonstrated how the mass fraction of coir fiber within the composite board enhances its ability to absorb neutron radiation, as evidenced by the significant Figure 4.
The Effect of Adding Coir Fiber on Absorption Capacity 5% to 99.
Notably, at a thickness of 1.
0 cm, nearly all neutron radiation is absorbed by the coir fiber composite These results further reinforced that coir fiber can serve as an alternative filler material in neutron radiation To meet the requirements for effective radiation shielding, it was necessary to determine the attenuation coefficient of the composite board.
Using Equation 1, it could calculate the attenuation coefficient for the coir fiber composite board, as illustrated in Figure 5.
Based on the analysis of the absorption capacity of coir fiber composite boards in absorbing neutron radiation, it was evident that the neutron absorption is influenced by both the mass fraction of coir fiber and the thickness of the composite board.
At a fiber mass fraction of 2.
0 g, the absorption rate ranges from 59.
4% to 97.
0 g, it ranges from 64.
3% to 98.
and at 4.
0 g, it ranges from Sitepu et.
/ Jurnal Riset Teknologi Pencegahan Pencemaran Industri Vol 16 No 1 .
1-8 Figure 5.
Linearization Graph of Neutron Absorption From Figure 5, it can be observed that the ability of coir fiber composite boards to absorb neutron radiation increases with the addition of the board's thickness.
The analysis showed that a higher mass fraction of coir fiber in the composite board enhances its radiation absorption capacity, as indicated by the increasing linear attenuation coefficients (AA) of the coir fiber composite board, which are 84, 4.
13, and 4.
80 cm-1, respectively.
Using Equation .
, the thickness of the radiation shield made from coir fiber composite required to reduce neutron radiation by 50% can be determined.
The results indicate that the half-value layer (HVL) for each mass fraction of coir fiber used is 0.
18, 0.
17, and 0.
14 cm.
These findings demonstrate that the mass fraction of coir fiber in neutron radiation shields can enhance their ability to absorb neutron radiation.
CONCLUSION
Based on the testing and analysis of coir fiber as a filler in neutron radiation shields, it can be concluded that coir fiber is a natural fiber that can serve as an alternative material for neutron radiation absorption.
The absorption capacity of composite boards at fiber mass fractions of 2.
gr ranged from 59.
0 gr from 64.
3 to 98.
and at 4.
0 gr from 73.
3% with linear attenuation coefficient (AA) for each coil fiber fraction is 3.
13 and 80 cm-1 and HVL of 0.
17 and 0.
14 cm.
The greater the mass fraction of coir fiber in the radiation shield, the more effective it becomes at absorbing neutron radiation.
REFERENCE