scholarly journals Potential Recovery of Silver (Ag) from X-ray Fixer Waste by Alkaline Treatment

2017 ◽  
Vol 7 (5) ◽  
pp. 2094-2097
Author(s):  
V. R. K. R. Galarpe ◽  
G. D. Leopoldo

The study aims to establish a chemical method of silver recovery from x-ray processing fixer waste by alkaline treatment using sodium hydroxide (NaOH). The samples used in the study were collected from selected hospitals and radiology centers in Cagayan de Oro City, Philippines. The NaOH precipitation method was employed by varying the amount of NaOH from 8.00 g to 15.00 g per 600 mL of the fixer waste sample. The recovered crude silver for the two sampling periods ranged from 0.88 g to 2.46 g. The method resulted to optimum recovery at pH 9. The One Way ANOVA indicates that there are significant differences on the amount of silver recovered when varying the amount of NaOH in “sampling A”. The Tukey Test further reveals that there exists an evident rise in the recovered silver using 10.00 g to 15.00 g of NaOH. In “sampling B” the amount of silver recovered does not significantly differ when varying the amount of NaOH used on average basis. The raw data, however, also revealed a significant rise in the amount of silver recovered using 10.00 g to 15.00 g of NaOH where pH was approximately 9.

2015 ◽  
Vol 1101 ◽  
pp. 286-289 ◽  
Author(s):  
Maya Rahmayanti ◽  
Sri Juari Santosa ◽  
Sutarno

Gallic acid-modified magnetites were synthesized by one and two-step reactions via the newly developed sonochemical co-precipitation method. The two-step reaction included the formation of magnetite powder and mixing the magnetite powder with gallic acid solution, while the one-step reaction did not go through the formation magnetite powder. The obtained gallic acid-modified magnetites were characterized by the Fourier Transform Infrared (FTIR) spectroscopy, the X-Ray Diffraction (XRD) and the Scanning Electron Microscopy (SEM). More over, the magnetic properties were studied by using a Vibrating Sample Magnetometer (VSM). The characterization results showed that there were differences in crystalinity, surface morphology and magnetic properties of products that were formed by one and two-step reactions.


2020 ◽  
Vol 6 (1) ◽  
pp. 62-69
Author(s):  
Soja Siti Fatimah ◽  
Wiwi Siswaningsih ◽  
Ali Kusrijadi ◽  
Fikri Aziz Shalahuddin

Silver recovery research from x-ray film waste by leaching and precipitation method using NaOH and Na2S aims to determine the optimum conditions in silver recovery. The parameters optimated in this study were the concentration of the precipitants, leaching temperature and the effect of the type of precipitants on the precipitated time. The results showed that the NaOH and Na2S precipitants were able to recover silver optimally at a concentration of 1.5 M. The optimum leaching temperature of the film with the Na2S precipitant to recover silver was at 25oC, whereas in the NaOH precipitant the film leaching temperature only affected the time of precipitation. Therefore, the formation of precipitate using Na2S is more efficient than NaOH, but the acquisition of silver is better to use NaOH than Na2S.


2019 ◽  
Vol 10 (2) ◽  
pp. 44-50
Author(s):  
Rinaldi Daswito ◽  
Rima Folentia ◽  
M Yusuf MF

One of the diseases that can be transmitted by flies is diarrhea. Green betel leaf contains essential oils, chavicol, arecoline, phenol, and tannins which function as plant-based insecticides. This study aimed to determine the effectiveness of green betel leaf extract (Piper betel) as a plant-based insecticide on the number of mortality of house flies (Musca domestica). The research was an experimental study used After Only Design used the One Way Anova test with a 95% confidence level. The samples used were 360 ​​house flies. Each treatment of 30 house flies with 4 repetitions and used three concentrations of green betel leaf extract (25%, 50%, 75%). The study was conducted at the Chemistry and Microbiology Laboratory of Health Polytechnic Tanjungpinang, while the location of the fly collection was at the Tokojo Garbage Collection Station in Bintan Regency. The number of mortality of house flies at a concentration of 25% was 81 heads (67.5%), 50% concentrations were 93 heads (77.5%), and at a concentration of 75% were 103 heads (85.83%). There was an effect of green betel leaf extract on the mortality of house flies (p-value 0.0001 <0.05) with the most effective concentration of 75%. Further research is needed to obtain a finished product utilizing green betel leaf extract as a vegetable insecticide, especially in controlling the fly vector. Need further research on the use of green betel leaf extract as a vegetable insecticide controlling the fly vector by taking into account the amount of spraying and the age of the fly.   Keywords: Green betel leaf extract , organic insecticide, houseflies


2020 ◽  
Vol 3 (2) ◽  
Author(s):  
Kavipriya K C ◽  
Sudha A P ◽  
Sujatha K ◽  
Sowmya Lakshmi K

The interest in miniaturization of particles revealed the hidden applications of metal oxides. The potential applications of the particles may vary when the size of the particle is reduced. One of the alternative routes to the conventional approach is the use of plant extract for the synthesis of metal oxides NPs. In the framework of this study, the ecofriendly MgO nanoparticles were synthesized using Acalypha Indica leaf extract,functioning as reducing and capping agent by co-precipitation method. The predecessor taken here was Magnesium Nitrate. The biologically synthesized MgO NPs were characterized by various techniques like X ray diffraction(XRD), Fourier Transform infrared spectroscopy(FTIR), Scanning electron microscope (SEM) with Energy Dispersive X-ray spectroscopy(EDX) profile and its antibacterial activity is evaluated against causative organisms. XRD studies confirmed the face centered cubic crystalline structure of MgO NPs and the average crystalline size of MgO NPs calculated using Scherer’s formula was found to be 13 nm. FTIR spectrum shows a significant Mg-O vibrational band. Purity, surface morphology and chemical composition of elements were confirmed by SEM with EDX. The SEM result shows the fine spherical morphology with the grain size range between 43nm to 62nm. Antimicrobial assay of MgO NPs was examined against gram positive and negative bacteria. Appreciated activity was observed on the Staphylococcus aureus bacterial species. In general, the renewed attempt of this facile approach gave the optimum results of multifunctional MgO NPs.


2020 ◽  
Vol 3 (2) ◽  
Author(s):  
Aarth R ◽  
Sudha A P ◽  
Sujatha B ◽  
Sowmya Lakshmi K

The phytosynthesis of n-type Cadmium Oxide Nanoparticles reduces the toxicity of the substance and makes it Eco-friendly. This Eco-friendly biosynthesis of CdO NPs was synthesized for the first time from the Queen of herbs, Ocimum Sanctum (holy basil).The biosynthesized Cadmium oxide was prepared using Ocimum leaf extract as a reductant and Cadmium Chloride and hydroxide as cadmium and oxide source materials by Co- Precipitation method. Thus obtained Cadmium Oxide Nanoparticles were characterized by different techniques such as X-ray diffraction (XRD), Fourier Transform infrared spectroscopy (FTIR), Scanning electron microscope (SEM),Energy dispersive X-ray spectroscopy(EDS) to study the structural and morphological properties. XRD pattern exhibited the formation of face centered cubic structure of CdO NPs with an average crystalline size of 11.5nm .The chemical bond formation of CdO NPs were confirmed by FTIR spectrum in the range of (400-4000cm-1). The SEM micrographs revealed the predominant formation of Cauliflower shape with a particle size in the range of 61-142nm. The high purity of the biosynthesized nanoparticles were confirmed by EDS analysis. Further it was tested against gram positive and gram negative bacterial strains and showed significant antibacterial activity. This biosynthetic research study opens an innovative window to progress our understanding of how CdO NPs shows resistance to different bacterial strains.


Crystals ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 832
Author(s):  
Edna X. Figueroa-Rosales ◽  
Javier Martínez-Juárez ◽  
Esmeralda García-Díaz ◽  
Daniel Hernández-Cruz ◽  
Sergio A. Sabinas-Hernández ◽  
...  

Hydroxyapatite (HAp) and hydroxyapatite/multi-walled carbon nanotube (MWCNT) composites were obtained by the co-precipitation method, followed by ultrasound-assisted and microwave radiation and thermal treatment at 250 °C. X-ray diffraction (XRD) confirmed the presence of a hexagonal phase in all the samples, while Fourier-transform infrared (FTIR) spectroscopy elucidated the interaction between HAp and MWCNTs. The photoluminescent technique revealed that HAp and the composite with non-functionalized MWCNTs present a blue luminescence, while the composite with functionalized MWCNTs, under UV-vis radiation shows an intense white emission. These findings allowed presentation of a proposal for the use of HAp and HAp with functionalized MWCNTs as potential materials for optoelectronic and medical applications.


Nanomaterials ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 366
Author(s):  
Margarita Gabrovska ◽  
Ivan Ivanov ◽  
Dimitrinka Nikolova ◽  
Jugoslav Krstić ◽  
Anna Maria Venezia ◽  
...  

Supported gold on co-precipitated nanosized NiAl layered double hydroxides (LDHs) was studied as an effective catalyst for medium-temperature water–gas shift (WGS) reaction, an industrial catalytic process traditionally applied for the reduction in the amount of CO in the synthesis gas and production of pure hydrogen. The motivation of the present study was to improve the performance of the Au/NiAl catalyst via modification by CeO2. An innovative approach for the direct deposition of ceria (1, 3 or 5 wt.%) on NiAl-LDH, based on the precipitation of Ce3+ ions with 1M NaOH, was developed. The proposed method allows us to obtain the CeO2 phase and to preserve the NiAl layered structure by avoiding the calcination treatment. The synthesis of Au-containing samples was performed through the deposition–precipitation method. The as-prepared and WGS-tested samples were characterized by X-ray powder diffraction, N2-physisorption and X-ray photoelectron spectroscopy in order to clarify the effects of Au and CeO2 loading on the structure, phase composition, textural and electronic properties and activity of the catalysts. The reduction behavior of the studied samples was evaluated by temperature-programmed reduction. The WGS performance of Au/NiAl catalysts was significantly affected by the addition of CeO2. A favorable role of ceria was revealed by comparison of CO conversion degree at 220 °C reached by 3 wt.% CeO2-modified and ceria-free Au/NiAl samples (98.8 and 83.4%, respectively). It can be stated that tuning the properties of Au/NiAl LDH via CeO2 addition offers catalysts with possibilities for practical application owing to innovative synthesis and improved WGS performance.


2020 ◽  
Vol 81 (1) ◽  
Author(s):  
K. N. Raghavendra ◽  
Kumar Arvind ◽  
G. K. Anushree ◽  
Tony Grace

Abstract Background Butterflies are considered as bio-indicators of a healthy and diversified ecosystem. Endosulfan was sprayed indiscriminately in large plantations of Kasaragod district, Kerala which had caused serious threats to the ecosystem. In this study, we surveyed the butterflies for their abundance and diversity in three differentially endosulfan-affected areas viz., Enmakaje—highly affected area, Periye—moderately affected area, Padanakkad—unaffected area, carried out between the end of the monsoon season and the start of the winter season, lasting approximately 100 days. Seven variables viz., butterfly abundance (N), species richness (S), Simpson’s reciprocal index (D), the Shannon–Wiener index (H′), the exponential of the Shannon–Wiener index (expH′), Pielou’s evenness (J) and species evenness (D/S), related to species diversity were estimated, followed by the one-way ANOVA (F = 25.01, p < 0.001) and the Kruskal-Wallis test (H = 22.59, p < 0.001). Results A population of three different butterfly assemblages comprised of 2300 butterflies which represented 61 species were encountered. Our results showed that Enmakaje displayed significantly lower butterfly diversity and abundance, compared to the other two communities. Conclusion So far, this is the first study concerning the effect of endosulfan on the biodiversity of butterfly in the affected areas of Kasaragod, Kerala, India. This study may present an indirect assessment of the persisting effects of endosulfan in the affected areas, suggesting its long-term effects on the ecosystem.


Nanomaterials ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 805
Author(s):  
Saif Ullah Khan ◽  
Rumman Zaidi ◽  
Feroz Shaik ◽  
Izharul Haq Farooqi ◽  
Ameer Azam ◽  
...  

Nanotechnology has received much attention in treating contaminated waters. In the present study, a facile co-precipitation method was employed to synthesize a novel iron and magnesium based binary metal oxide using a stoichiometrically fixed amount of FeNO3.9H2O and MgNO3.6H2O in a proportion of molar concentration 1:1 and was later evaluated in removing As (III) from contaminated waters. Characterization of the prepared nanomaterial was done using X-ray diffraction (XRD), scanning electron microscopy (SEM), Energy Dispersive X-Ray Analysis (EDAX) and ultraviolet–visible spectrophotometry (UV-VIS). Experimental studies on batch scale were carried out, examining the effect of varying initial concentrations of metal, adsorbent dosage, application time and initial pH on removal efficiency. Arsenic removal increased on increasing adsorbent dosage (0.1–1 g/L) but trend reversed on increasing initial arsenic concentration attaining qmax of 263.20 mg/g. Adsorption was quite efficient in pH range 4–8. Freundlich fitted better for adsorption isotherm along with following Pseudo-2nd order kinetics. The reusability and effect of co-existing ions on arsenic adsorption, namely SO42−, CO32− and PO43− were also explored with reusability in 1st and 2nd cycles attained adsorptive removal up to 77% and 64% respectively. The prepared nano-adsorbent showed promising results in terms of high arsenic uptake (qmax of 263.20 mg/g) along with facile and cost-effective synthesis. Thus, the co-precipitation technique used in this work is a simple one step procedure without any use of any precursor as compared to most of the other procedures used for synthesis.


Coatings ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 570
Author(s):  
Olga Sánchez ◽  
Manuel Hernández-Vélez

ZnOTe compounds were grown by DC magnetron cosputtering from pure Tellurium (Te) and Zinc (Zn) cathodes in O2/Ar atmosphere. The applied power on the Zn target was constant equal to 100 W, while the one applied on the Te target took two values, i.e., 5 W and 10 W. Thus, two sample series were obtained in which the variable parameter was the distance from the Te targets to the substrate. Sample compositions were determined by Rutherford Backscattering Spectroscopy (RBS) experiments. Structural analysis was done using X-Ray diffraction (XRD) spectrometry and the growth of the hexagonal w-ZnO phase was identified in the XRD spectra. RBS results showed high bulk homogeneity of the samples forming ZnOTe alloys, with variable Te molar fraction (MF) ranging from 0.48–0.6% and from 1.9–3.1% for the sample series obtained at 5 W and 10 W, respectively. The results reflect great differences between the two sample series, particularly from the structural and optical point of view. These experiments point to the possibility of Te doping ZnO with the permanence of intrinsic defects, as well as the possibility of the formation of other Te solid phases when its content increases. The results and appreciable variations in the band gap transitions were detected from Photoluminescence (PL) measurements.


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