- Email: [email protected]
Effect of the BaO addition on properties of alkali borosilicate glasses from sub-bituminous fly ash
Available online at www.sciencedirect.com
ScienceDirect Materials Today: Proceedings 5 (2018) 14189–14193
www.materialstoday.com/proceedings
SACT 2016
Effect of the BaO addition on properties of alkali borosilicate glasses from sub-bituminous fly ash W. Rachniyoma,b,*, P. Wiwatkanjanab, Y. Ruangtaweepa,b, J. Kaewkhaoa,b a
Center of Excellence in Glass Technology and Materials Science (CEGM), Nakhon Pathom Rajabhat University, Nakhon Pathom 73000, Thailand b Science Program, Faculty of Science and Technology, Nakhon Pathom Rajabhat University, Nakhon Pathom 73000, Thailand
Abstract Alkali borosilicate glasses were prepared by using sub-bituminous fly ash (SFA) and B2O3 as raw material, Na2O as fluxing agent. The effects of BaO addition were investigated in formula x BaO : (65-x) B2O3 : 20 Na2O : 15 SFA (where x = 5, 10, 15, 20 and 25 wt%.) and melted at 1,200 ºC by melt quenched technique. All glass samples were analyzed then compared their properties of density, refractive index, hardness, absorption spectra and radiation shielding properties. The results were showed better properties with increasing of BaO content. The density, refractive index and hardness values of glass samples were increased with increasing of BaO content and showed highest value at 2.857 g/cm3, 1.5567 and 494.867 HV, respectively. The result of absorption spectra found the ferric and ferrous ions peaks occurred at 440 nm and 1,050 nm. The color of glass samples caused by ferric ions which obtianed from SFA. However, the color of glasses with higher BaO were showed more light green and brightness. The half value layer (HVL) of glass found to be decreased with higher BaO concentration, due to higher gamma ray absorption cross section of Ba in glass matrices. The glass containing 25 wt%. of BaO is the best shielding glass in this experiment and better than serpentite-hematite concrete. © 2017 Elsevier Ltd. All rights reserved. Selection and/or Peer-review under responsibility of SACT 2016. Keywords: alkli borisilicate glass; coal fly ash; sub-bituminous
1. Introduction Coal has been used as main solid fuel for the power generation in Thailand for decades. Coal was burned in boilers for driving steam engines which converted kinetic energy to electricity. Under burning process, the physical
* Corresponding author. Tel.: +66 866-009-220 ; fax: +66 3426-1065 . E-mail address: [email protected] 2214-7853 © 2017 Elsevier Ltd. All rights reserved. Selection and/or Peer-review under responsibility of SACT 2016.
14190
W. Rachniyom et al./ Materials Today: Proceedings 5 (2018) 14189–14193
and chemical properties of coal have been changed in to solid waste which knows as coal ash. Coal ash is classified in two forms, which included slag and fly ash. Coal fly ash is seemed to concern in current. Because of it has small size and easily to leaks in environmental. Its compositions consisted with many hazardous elements, i.e., Cd, Cr, Ni, Pb and organic compounds (PCBs, PAHs) [1]. Currently, coal fly ash is widely utilized in many applications such as fertilizer, production of zeolite, construction material, mined land backfills, etc [2]. These applications can reduce environmental impacts by reuse hazardous waste. Although coal fly ash can utilize in many applications, but its consumption is remained low and does not correlate with quantity of fly ash waste in Thailand. The main utilizations were recycled to construction materials as concrete and brick. However, chemical composition of fly ash can be represented by large amount of SiO2, Al2O3 and small amount of transition metal oxides (Fe2O3, MnO, etc.) [3]. In generally, SiO2 is a glass network former which use as raw material in glass and ceramic production. So, it is possible to utilize coal fly ash in glass production [4]. This is a good technique to reuse hazardous material into useful materials. The hazardous metal elements are homogeneous incorporate into a glassy matrix [5]. The objective of current research was produced glasses with using sub-bituminous fly ash (SFA) in Thailand as raw material. The chemicals of glasses were prepared with 20 wt.% of SFA, and mixed it with oxides of boron (B2O3), sodium (Na2O) and added barium oxide (BaO) in difference proportions. The glasses were analyzed in physical, mechanical, absorption spectra and radiation shielding properties for comparing the effect of various BaO contents. These data will be helpful for utilization of glass from coal fly ash in another application. 2. Experiment The SFA in this work were procured from coal-fired thermal power plant, Thailand. Energy-Dispersive X-Ray Fluorescence (ED-XRF) was used for investigating chemical compositions of coal fly ash and showed in Table 1. The square flat glasses were prepared according to propertions of xBaO : (65-x)B2O3 : 20Na2O :15SFA (where x = 0, 10, 15, 20 and 25 wt%.) by using the melt-quenching technique. The chemical mixtures of each sample (15g) were placed in alumina batch before melted in an electrical furnace at 1,200 °C for 3 hour. After that, these melts were poured in stainless steel mold and quenched at room temperature in the air to form glasses. The thermal residue stress of glasses were reduced by annealing at 500 °C for 3 hour then shut off furnace. The glasses were slow cooled down to room temperature in furnace. All glass samples were cut and polished in size 1x1x0.2 cm for investigating properties. The densities of glass samples were investigated according to Archimedes principle. The weights of glasses were measured on a sensitive microbalance model AND, HR200. The abbe refractometer (ATAGO-3T) was used to identity refractive index values of glasses, which used mono-bromonaphthalene as an adhesive coating. The Vicker’s hardness (Enkay DHV-1000) was evaluated the hardness value of glasses with load of 0.1 kg and compressed for 10s. The UV-Vis-NIR spectrophotometer model Shimadzu UV-3600 were used to measure the absorption spectra of glasses in rang 200-2,000 nm. Table 1. Chemical components by weight of sub-bituminous fly ash. % weight Compound Sub-bituminous fly ash
SiO2
Al2O3
Fe2O3
CaO
TiO2
K2O
P2O5
SO3
MnO
ZnO
CuO
NiO
a
49.61
28.99
14.61
2.24
1.98
1.08
0.77
0.46
0.14
0.04
0.02
0.01
0.05
LOI
*LOI = Loss on ignition
For the radiation shielding properties, the equipment was setup as Fig. 1 to measure mass attenuation coefficient. Cs-137 was selected as radioactive source which obtained from the Office of Atoms for Peace (OAP), Bangkok, Thailand. It was placed in a Pb container with 3 mm of collimator. The glass samples were placed between source and NaI(Tl) detector. The distance of narrow beam will travel though glass samples at 140 mm. and though to NaI(Tl) detector at 330 mm. The gamma-ray intensity was detected by NaI(Tl) scintillation detector with 8% of energy resolution at 662 keV (BICRON model 2M2/2), and was recorded by multi-channel analyzer (CANBERRA
W. Rachniyom et al./ Materials Today: Proceedings 5 (2018) 14189–14193
14191
PCbased) [6,7]. The software (WinXCom) was determined the mass attenuation coefficients in this experimental, based on the rule of mixture.
Fig. 1. Experimental setup for mass attenuation coefficient determination [6].
3. Results and discussion The density and refractive index properties of glass samples are shown in Fig. 2. The density of glass samples increases with BaO addition into the network. These changes can be interpreted from the replacement of the molecular weight of BaO in the glass structure. Because of molecular weight of BaO (153.33 g/mol) is higher than B2O3 (69.62 g/mol). The refractive index values were increased with increasing concentrations of BaO. They were similar trend with the density values. These results are corresponding with the classical dielectric theory, the refractive index values were depended with density and polarisability of the atom in a given materials [8]. Similarly, the hardness values are shown in Fig. 3. It is seen that glass structure is more rigid with increasing of Bao concentration. The glass without BaO content is poor hardness value at 328.43 HV, while the highest value glass sample is 494.87 HV at 25 wt%. of BaO. The UV-Vis-NIR examinations were operated in wave length from 200 to 2000 nm. The results were given in Fig. 4. The absorption spectra of iron were occurred in this data, including the iron(ii) (ferrous iron) and iron(iii) (ferric iron). As a result of raw material contained rich in iron oxide around 14.16 wt%. (Table 1). It has been affected two effects in absorption spectra. First, the ferric iron (Fe3+ (6A1g(S)→4T2g(G)) were occurred shoulder absorption bands in wavelength around 480 nm. It is in visible spectrum, as a result to observed a yellow to brown color of glass samples. Second, the wavelength around 1,050 nm was observed board peaks due to ferrous iron (Fe2+ (5Eg→5T2)) [9,10]. The higher BaO content has been affected to weak absorption band at 1,050 nm. 1.57 2.9
500
1.56
2.7 2.6 2.5
1.54 y = 0.0235x + 2.2678 R² = 0.996
1.53
y = 0.0021x + 1.5061 R² = 0.9969
1.52
2.4
Density Refractive index
2.3
1.51
Vicker's Hardness (HV)
480 1.55
Refractive index
Density (g/cm3)
2.8
460 440 420
y = 6.9025x + 336.28 R² = 0.971
400 380 360 340 320
2.2
0
5
10
15
20
25
1.50
BaO (wt%.) Fig. 2. The densities and the refractive indexes of glass samples.
0
5
10
15
20
25
BaO (wt%.) Fig. 3. The Vicker’s hardness of glass samples.
14192
W. Rachniyom et al./ Materials Today: Proceedings 5 (2018) 14189–14193
Fe3+
Absorbant (arb. unit)
Fe2+
x=25 x=20 x=15 x=10 x=5 x=0
200 400 600 800 1000 1200 1400 1600 1800 2000
Wavelength (nm) Fig. 4. The absorption spectra of glass samples.
Fig. 5. The CIE L*a*b* of glass samples. 4.8 Comercial window glass
4.6
7.8
4.4
7.7
HVL (cm)
mx10
-2
2 cm /g)
4.2
7.6
7.5
Serpentite concrete
4.0 Ordinary concrete
3.8
This work Serpentite-Hematite concrete
3.6
Theoretical Experimental
7.4
3.4 3.2
7.3
0
5
10
15
20
25
BaO (wt%.) Fig. 6. The mass attenuation coefficients of glass samples at gamma-ray energy 662 keV.
0
5
10
15
20
25
BaO (wt%.) Fig. 7. The half value layer of glass samples.
The colorants of glass samples were reported with CIE L*a*b*. The color of glass without BaO is red and less blue color. The increasing of BaO content have been effect to stronger blue color as shown in Fig. 5. In addition, increasing of BaO content were affected to increase the brightness (L*) of glass samples. The gamma-ray with an energy at 662 keV was used to identify shielding properties of all glass samples. The comparison between theoretical and experimental values of mass attenuation coefficients of glass samples are shown in Fig. 6. The experimental values of mass attenuation coefficients were calculated from intensities of incident (I0) and transmitted (I) gamma-ray energies at 662 keV, and the theoretical values of mass attenuation coefficients were
W. Rachniyom et al./ Materials Today: Proceedings 5 (2018) 14189–14193
14193
determined from WinXCom [7,11]. For the theoretical value of mass attenuation coefficients, the glass samples were represented higher value when the BaO concentrations increases. While, the experimental values were very close the theoretical values of mass attenuation coefficients. The errors between experimental and theoretical values are mainly attributed to non-stoichiometry ratio of glass formula after melting at high temperature [7]. The comparison between half-value layers of all glass samples and some reference shielding materials is shown in Fig. 7. The half-value layer of reference materials were obtained from literature [12,13]. It can observe that all glasses have better shielding properties than commercial window glass and serpentite concrete. Besides, glass sample is better shielding properties than ordinary concrete after added BaO at 10 wt.%. Moreover, glass sample is better shielding properties than serpentite-hematite concrete after added BaO over 15 wt.%. 4. Conclusion The densities, refractive indexes and hardness values of glass samples were increased with increasing of BaO contents and the best glass in this experiment was the glass containing 25 wt%. of BaO. These values are shown by 2.857 g/cm3, 1.5567 and 494.867 HV, respectively. The absorption spectra found the characteristic of ferric and ferrous ions at 480 nm and 1,050 nm. However, the peaks of ferrous ion were dropped when increasing of BaO concentrations, the radiation shielding properties of glassed were identified with 662 keV of gamma-ray energy. The mass attenuation coefficient values of glass samples were in good agreement between theoretical and experiment value. Finally, all glass sample showed better shielding properties than commercial window glass and serpentite concrete. The shielding property of glasses were better than serpentite-hematite concrete when BaO concentrations were higher than 15 wt%. These data were demonstrated that the density, refractive index and hardness of glassed in this experiment were improved with BaO addition. Furthermore, they can be utilized as radiation shielding material. Acknowledgements The authors would like to thank National Research Council of Thailand (NRCT) and Nakhon Pathom Rajabhat University (NPRU) for support this research. References [1] M.S. Sabry, S.H. Peter, T.D. Christos, J. Enviro. Manag. 145 (2014) 249-267. [2] J. Wang, Q. Qin, S. Hu, K. Wu a, Journal of Cleaner Production. 112 (2016) 631-638. [3] J. Liua, Y. Dong, X. Dong, S. Hampshire, L. Zhu, Z. Zhu, L. Li, J. Eur. Ceram. Soc. 36 (2016) 1059-1071. [4] P. Fei, L. Kaiming H. Anmin, S. Hua, Fuel. 83 (2004) 1973–1977. [5] B. Luisa, L. Isabella, M. Tiziano, Q. Ignasi, M.R. Jeśus, R. Maximina, Design, Fuel. 78 (1999) 271-276. [6] S. Tuscharoea, J. Kaewkhao, P. Limsuwana, w. Chewpraditkula, Nucl. Sci. Tech. 1 (2011) 110-113. [7] S. Tuscharoen, J. Kaewkhao, P. Limkitjaroenporn, P. Limsuwan, W. Chewpraditkul, Ann. Nucl. Energ. 49 (2012) 109–113 [8] Y. Ruangtaweep, J. Kaewkhao, K. Kirdsiri, C. Kedkaew, P. Limsuwan, Mater. Sci. Eng. 18 (2011) 112008 [9] P.A. Bingham, J.M. Parker, T. Searle, J.M. Williams, I. Smith, C. R. Chimie. 5 (2002) 787–796. [10] C.R. BamFord, Glass Sci. Tech. 2 (1977) 34-38. [11] N. Singh, K.J. Singh, K. Singh, H. Singh, Radiat. Meas. 41 (2006) 84-88. [12] N. Singh, K.J. Singh, K. Singh, H. Singh, Nucl. Instrum. Meth. Phys. Res. Section B. 225 (2004) 305–309. [13] S. Singh, A. Kumar, D. Singh, K.S. Thind, G.S. Mudahar, Nucl. Instrum. Meth. Phys. Res. Section B. 266 (2008) 140–146.
ScienceDirect Materials Today: Proceedings 5 (2018) 14189–14193
www.materialstoday.com/proceedings
SACT 2016
Effect of the BaO addition on properties of alkali borosilicate glasses from sub-bituminous fly ash W. Rachniyoma,b,*, P. Wiwatkanjanab, Y. Ruangtaweepa,b, J. Kaewkhaoa,b a
Center of Excellence in Glass Technology and Materials Science (CEGM), Nakhon Pathom Rajabhat University, Nakhon Pathom 73000, Thailand b Science Program, Faculty of Science and Technology, Nakhon Pathom Rajabhat University, Nakhon Pathom 73000, Thailand
Abstract Alkali borosilicate glasses were prepared by using sub-bituminous fly ash (SFA) and B2O3 as raw material, Na2O as fluxing agent. The effects of BaO addition were investigated in formula x BaO : (65-x) B2O3 : 20 Na2O : 15 SFA (where x = 5, 10, 15, 20 and 25 wt%.) and melted at 1,200 ºC by melt quenched technique. All glass samples were analyzed then compared their properties of density, refractive index, hardness, absorption spectra and radiation shielding properties. The results were showed better properties with increasing of BaO content. The density, refractive index and hardness values of glass samples were increased with increasing of BaO content and showed highest value at 2.857 g/cm3, 1.5567 and 494.867 HV, respectively. The result of absorption spectra found the ferric and ferrous ions peaks occurred at 440 nm and 1,050 nm. The color of glass samples caused by ferric ions which obtianed from SFA. However, the color of glasses with higher BaO were showed more light green and brightness. The half value layer (HVL) of glass found to be decreased with higher BaO concentration, due to higher gamma ray absorption cross section of Ba in glass matrices. The glass containing 25 wt%. of BaO is the best shielding glass in this experiment and better than serpentite-hematite concrete. © 2017 Elsevier Ltd. All rights reserved. Selection and/or Peer-review under responsibility of SACT 2016. Keywords: alkli borisilicate glass; coal fly ash; sub-bituminous
1. Introduction Coal has been used as main solid fuel for the power generation in Thailand for decades. Coal was burned in boilers for driving steam engines which converted kinetic energy to electricity. Under burning process, the physical
* Corresponding author. Tel.: +66 866-009-220 ; fax: +66 3426-1065 . E-mail address: [email protected] 2214-7853 © 2017 Elsevier Ltd. All rights reserved. Selection and/or Peer-review under responsibility of SACT 2016.
14190
W. Rachniyom et al./ Materials Today: Proceedings 5 (2018) 14189–14193
and chemical properties of coal have been changed in to solid waste which knows as coal ash. Coal ash is classified in two forms, which included slag and fly ash. Coal fly ash is seemed to concern in current. Because of it has small size and easily to leaks in environmental. Its compositions consisted with many hazardous elements, i.e., Cd, Cr, Ni, Pb and organic compounds (PCBs, PAHs) [1]. Currently, coal fly ash is widely utilized in many applications such as fertilizer, production of zeolite, construction material, mined land backfills, etc [2]. These applications can reduce environmental impacts by reuse hazardous waste. Although coal fly ash can utilize in many applications, but its consumption is remained low and does not correlate with quantity of fly ash waste in Thailand. The main utilizations were recycled to construction materials as concrete and brick. However, chemical composition of fly ash can be represented by large amount of SiO2, Al2O3 and small amount of transition metal oxides (Fe2O3, MnO, etc.) [3]. In generally, SiO2 is a glass network former which use as raw material in glass and ceramic production. So, it is possible to utilize coal fly ash in glass production [4]. This is a good technique to reuse hazardous material into useful materials. The hazardous metal elements are homogeneous incorporate into a glassy matrix [5]. The objective of current research was produced glasses with using sub-bituminous fly ash (SFA) in Thailand as raw material. The chemicals of glasses were prepared with 20 wt.% of SFA, and mixed it with oxides of boron (B2O3), sodium (Na2O) and added barium oxide (BaO) in difference proportions. The glasses were analyzed in physical, mechanical, absorption spectra and radiation shielding properties for comparing the effect of various BaO contents. These data will be helpful for utilization of glass from coal fly ash in another application. 2. Experiment The SFA in this work were procured from coal-fired thermal power plant, Thailand. Energy-Dispersive X-Ray Fluorescence (ED-XRF) was used for investigating chemical compositions of coal fly ash and showed in Table 1. The square flat glasses were prepared according to propertions of xBaO : (65-x)B2O3 : 20Na2O :15SFA (where x = 0, 10, 15, 20 and 25 wt%.) by using the melt-quenching technique. The chemical mixtures of each sample (15g) were placed in alumina batch before melted in an electrical furnace at 1,200 °C for 3 hour. After that, these melts were poured in stainless steel mold and quenched at room temperature in the air to form glasses. The thermal residue stress of glasses were reduced by annealing at 500 °C for 3 hour then shut off furnace. The glasses were slow cooled down to room temperature in furnace. All glass samples were cut and polished in size 1x1x0.2 cm for investigating properties. The densities of glass samples were investigated according to Archimedes principle. The weights of glasses were measured on a sensitive microbalance model AND, HR200. The abbe refractometer (ATAGO-3T) was used to identity refractive index values of glasses, which used mono-bromonaphthalene as an adhesive coating. The Vicker’s hardness (Enkay DHV-1000) was evaluated the hardness value of glasses with load of 0.1 kg and compressed for 10s. The UV-Vis-NIR spectrophotometer model Shimadzu UV-3600 were used to measure the absorption spectra of glasses in rang 200-2,000 nm. Table 1. Chemical components by weight of sub-bituminous fly ash. % weight Compound Sub-bituminous fly ash
SiO2
Al2O3
Fe2O3
CaO
TiO2
K2O
P2O5
SO3
MnO
ZnO
CuO
NiO
a
49.61
28.99
14.61
2.24
1.98
1.08
0.77
0.46
0.14
0.04
0.02
0.01
0.05
LOI
*LOI = Loss on ignition
For the radiation shielding properties, the equipment was setup as Fig. 1 to measure mass attenuation coefficient. Cs-137 was selected as radioactive source which obtained from the Office of Atoms for Peace (OAP), Bangkok, Thailand. It was placed in a Pb container with 3 mm of collimator. The glass samples were placed between source and NaI(Tl) detector. The distance of narrow beam will travel though glass samples at 140 mm. and though to NaI(Tl) detector at 330 mm. The gamma-ray intensity was detected by NaI(Tl) scintillation detector with 8% of energy resolution at 662 keV (BICRON model 2M2/2), and was recorded by multi-channel analyzer (CANBERRA
W. Rachniyom et al./ Materials Today: Proceedings 5 (2018) 14189–14193
14191
PCbased) [6,7]. The software (WinXCom) was determined the mass attenuation coefficients in this experimental, based on the rule of mixture.
Fig. 1. Experimental setup for mass attenuation coefficient determination [6].
3. Results and discussion The density and refractive index properties of glass samples are shown in Fig. 2. The density of glass samples increases with BaO addition into the network. These changes can be interpreted from the replacement of the molecular weight of BaO in the glass structure. Because of molecular weight of BaO (153.33 g/mol) is higher than B2O3 (69.62 g/mol). The refractive index values were increased with increasing concentrations of BaO. They were similar trend with the density values. These results are corresponding with the classical dielectric theory, the refractive index values were depended with density and polarisability of the atom in a given materials [8]. Similarly, the hardness values are shown in Fig. 3. It is seen that glass structure is more rigid with increasing of Bao concentration. The glass without BaO content is poor hardness value at 328.43 HV, while the highest value glass sample is 494.87 HV at 25 wt%. of BaO. The UV-Vis-NIR examinations were operated in wave length from 200 to 2000 nm. The results were given in Fig. 4. The absorption spectra of iron were occurred in this data, including the iron(ii) (ferrous iron) and iron(iii) (ferric iron). As a result of raw material contained rich in iron oxide around 14.16 wt%. (Table 1). It has been affected two effects in absorption spectra. First, the ferric iron (Fe3+ (6A1g(S)→4T2g(G)) were occurred shoulder absorption bands in wavelength around 480 nm. It is in visible spectrum, as a result to observed a yellow to brown color of glass samples. Second, the wavelength around 1,050 nm was observed board peaks due to ferrous iron (Fe2+ (5Eg→5T2)) [9,10]. The higher BaO content has been affected to weak absorption band at 1,050 nm. 1.57 2.9
500
1.56
2.7 2.6 2.5
1.54 y = 0.0235x + 2.2678 R² = 0.996
1.53
y = 0.0021x + 1.5061 R² = 0.9969
1.52
2.4
Density Refractive index
2.3
1.51
Vicker's Hardness (HV)
480 1.55
Refractive index
Density (g/cm3)
2.8
460 440 420
y = 6.9025x + 336.28 R² = 0.971
400 380 360 340 320
2.2
0
5
10
15
20
25
1.50
BaO (wt%.) Fig. 2. The densities and the refractive indexes of glass samples.
0
5
10
15
20
25
BaO (wt%.) Fig. 3. The Vicker’s hardness of glass samples.
14192
W. Rachniyom et al./ Materials Today: Proceedings 5 (2018) 14189–14193
Fe3+
Absorbant (arb. unit)
Fe2+
x=25 x=20 x=15 x=10 x=5 x=0
200 400 600 800 1000 1200 1400 1600 1800 2000
Wavelength (nm) Fig. 4. The absorption spectra of glass samples.
Fig. 5. The CIE L*a*b* of glass samples. 4.8 Comercial window glass
4.6
7.8
4.4
7.7
HVL (cm)
mx10
-2
2 cm /g)
4.2
7.6
7.5
Serpentite concrete
4.0 Ordinary concrete
3.8
This work Serpentite-Hematite concrete
3.6
Theoretical Experimental
7.4
3.4 3.2
7.3
0
5
10
15
20
25
BaO (wt%.) Fig. 6. The mass attenuation coefficients of glass samples at gamma-ray energy 662 keV.
0
5
10
15
20
25
BaO (wt%.) Fig. 7. The half value layer of glass samples.
The colorants of glass samples were reported with CIE L*a*b*. The color of glass without BaO is red and less blue color. The increasing of BaO content have been effect to stronger blue color as shown in Fig. 5. In addition, increasing of BaO content were affected to increase the brightness (L*) of glass samples. The gamma-ray with an energy at 662 keV was used to identify shielding properties of all glass samples. The comparison between theoretical and experimental values of mass attenuation coefficients of glass samples are shown in Fig. 6. The experimental values of mass attenuation coefficients were calculated from intensities of incident (I0) and transmitted (I) gamma-ray energies at 662 keV, and the theoretical values of mass attenuation coefficients were
W. Rachniyom et al./ Materials Today: Proceedings 5 (2018) 14189–14193
14193
determined from WinXCom [7,11]. For the theoretical value of mass attenuation coefficients, the glass samples were represented higher value when the BaO concentrations increases. While, the experimental values were very close the theoretical values of mass attenuation coefficients. The errors between experimental and theoretical values are mainly attributed to non-stoichiometry ratio of glass formula after melting at high temperature [7]. The comparison between half-value layers of all glass samples and some reference shielding materials is shown in Fig. 7. The half-value layer of reference materials were obtained from literature [12,13]. It can observe that all glasses have better shielding properties than commercial window glass and serpentite concrete. Besides, glass sample is better shielding properties than ordinary concrete after added BaO at 10 wt.%. Moreover, glass sample is better shielding properties than serpentite-hematite concrete after added BaO over 15 wt.%. 4. Conclusion The densities, refractive indexes and hardness values of glass samples were increased with increasing of BaO contents and the best glass in this experiment was the glass containing 25 wt%. of BaO. These values are shown by 2.857 g/cm3, 1.5567 and 494.867 HV, respectively. The absorption spectra found the characteristic of ferric and ferrous ions at 480 nm and 1,050 nm. However, the peaks of ferrous ion were dropped when increasing of BaO concentrations, the radiation shielding properties of glassed were identified with 662 keV of gamma-ray energy. The mass attenuation coefficient values of glass samples were in good agreement between theoretical and experiment value. Finally, all glass sample showed better shielding properties than commercial window glass and serpentite concrete. The shielding property of glasses were better than serpentite-hematite concrete when BaO concentrations were higher than 15 wt%. These data were demonstrated that the density, refractive index and hardness of glassed in this experiment were improved with BaO addition. Furthermore, they can be utilized as radiation shielding material. Acknowledgements The authors would like to thank National Research Council of Thailand (NRCT) and Nakhon Pathom Rajabhat University (NPRU) for support this research. References [1] M.S. Sabry, S.H. Peter, T.D. Christos, J. Enviro. Manag. 145 (2014) 249-267. [2] J. Wang, Q. Qin, S. Hu, K. Wu a, Journal of Cleaner Production. 112 (2016) 631-638. [3] J. Liua, Y. Dong, X. Dong, S. Hampshire, L. Zhu, Z. Zhu, L. Li, J. Eur. Ceram. Soc. 36 (2016) 1059-1071. [4] P. Fei, L. Kaiming H. Anmin, S. Hua, Fuel. 83 (2004) 1973–1977. [5] B. Luisa, L. Isabella, M. Tiziano, Q. Ignasi, M.R. Jeśus, R. Maximina, Design, Fuel. 78 (1999) 271-276. [6] S. Tuscharoea, J. Kaewkhao, P. Limsuwana, w. Chewpraditkula, Nucl. Sci. Tech. 1 (2011) 110-113. [7] S. Tuscharoen, J. Kaewkhao, P. Limkitjaroenporn, P. Limsuwan, W. Chewpraditkul, Ann. Nucl. Energ. 49 (2012) 109–113 [8] Y. Ruangtaweep, J. Kaewkhao, K. Kirdsiri, C. Kedkaew, P. Limsuwan, Mater. Sci. Eng. 18 (2011) 112008 [9] P.A. Bingham, J.M. Parker, T. Searle, J.M. Williams, I. Smith, C. R. Chimie. 5 (2002) 787–796. [10] C.R. BamFord, Glass Sci. Tech. 2 (1977) 34-38. [11] N. Singh, K.J. Singh, K. Singh, H. Singh, Radiat. Meas. 41 (2006) 84-88. [12] N. Singh, K.J. Singh, K. Singh, H. Singh, Nucl. Instrum. Meth. Phys. Res. Section B. 225 (2004) 305–309. [13] S. Singh, A. Kumar, D. Singh, K.S. Thind, G.S. Mudahar, Nucl. Instrum. Meth. Phys. Res. Section B. 266 (2008) 140–146.