• 자원환경지질
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• 제38권5호
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• pp.587-597
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• 2005

본 논문은 지하수에서의 비소화학과 발생에 관한 것이다. 특히, 비소종의 물리화학적 특성, As(III)의 산화, 비소의 거동과 관련된 지화학 과정, 토양으로부터 비소의 용해, 비소함유 광물로부터 비소용출 메커니즘을 주로 다루고 있다.

• Mass Spectrometry Letters
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• 제12권3호
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• pp.106-111
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• 2021

Several pretreatment methods have been developed to reduce the inorganic arsenic, which is known to be highly harmful to humans, among various arsenic species present in hijiki and rice. The pretreatment methods were selected and developed as methods that can be non-harmful even after treatment and easily applied. Hijiki was applied by two methods. One was soaking in water at room temperature for various durations and the other was boiling of it in water for a short period of time. Rice was soaked in water with different rice-to-water ratios for various durations. The most effective method that reduced the inorganic arsenic in hijiki was to repeat parboiling for 5 minutes twice, which led to 79% reduction of the inorganic arsenic in it. In the case of rice, soaking for 24 hours at the ratio of 1:5 (rice:water) resulted in 51% reduction of inorganic arsenic in rice.

• 분석과학
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• 제32권1호
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• pp.1-6
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• 2019

Chinese brake fern (Pteris vittata) has potential for application in the phytoremediation of arsenic introduced by lead arsenate-based pesticides. In this study, Chinese brake ferns were used to extract arsenic, mainly in field and greenhouse experiments, and to assess the performance of simultaneous phytoaccumulation of arsenic and lead from homogenized soil in the greenhouse, with the application of EDTA and electric potential. The ferns have been shown to be effective in accumulating high concentrations of arsenic, and extracting both arsenic and lead from the contaminated soil, with the addition of a chelating agent, EDTA. The maximum increase in lead accumulation in the ferns was 9.2 fold, with a 10 mmol/kg addition of EDTA. In addition, the application of EDTA in combination with electric potential increased the lead accumulation in ferns by 10.6 fold at 5 mmol/kg of EDTA and 40 V (dc), compared to controls. Therefore, under application of EDTA and electric potential, Chinese brake fern is able to extract arsenic and lead simultaneously from soil contaminated by lead arsenate.

• 한국환경보건학회지
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• 제32권1호
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• pp.8-18
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• 2006

The aim of this study is to evaluate the emission characteristics of mercury, lead, arsenic, and selenium from medium size municipal solid waste incinerators(MSWIs) in Korea. The concentrations of mercury, lead, arsenic, and selenium emitted from medium size MSWI stack were $2.67\;{\mu}g/Sm^3,\;0.38\;mg/Sm^3,\;1.33\;{\mu}g/Sm^3,\;0.28\;{\mu}g/Sm^3$, respectively. The concentration levels of mercury, lead, arsenic in flue gas from medium size MSW incinerator stacks selected were nearly detected under the Korea criteria level. Removal efficiencies of mercury, lead, arsenic, and selenium in waste heat boiler(WHE) and cooling tower(CT) were $90.36\%,\;69.76\%,\;43.04\%,\;40.64\%$, respectively. In general, the removal efficiencies of mercury and lead in WHE were higher than those of arsenic and selenium in WHE. Emission gas temperature reduction from waste heat boiler(WHB) and cooling tower(CT) can control mercury and lead of medium size MSWIs. To evaluate the relationship between mercury, lead, arsenic, selenium of fly ash and those of flue gas, it was carried out to correlation analysis of each metal concentration in the fly ash and in the flue gas from medium size MSWIs. From the correlation analysis, the coefficients of mercury, lead, arsenic, and selenium were 0.61, -0.38, 0.87, 0.28, respectively. The results of correlation analysis revealed that it should be highly positive to the correlation coefficients of mercury and arsenic in the fly ash and those of the flue gas emitted from medium size MSWIs. As it were, the concentrations of mercury and arsenic of flue gas from medium size MSWIs are high unless mercury and arsenic in fly ash are properly controlled in dust collection step in medium size MSWIs. It was also concluded that mercury, lead, arsenic, and selenium from MSWIs stacks could be controlled by waste heat boiler(WHE) and dust collecting step in medium size MSWIs.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2002년도 추계학술대회 논문집 Vol.15
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• pp.391-394
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• 2002

There has recently been much interest and research in developing digital x-ray systems based on using amorphous selenium(a-Se) photoconductors as the image receptor. The amorphous selenium layer that is currently being studied for use as an x-ray photoconductor is not pure a-Se but rather amorphous selenium alloyed with arsenic. We fabricated samples using the selenium and arsenic alloy with various concentrations of the arsenic. In this work, x-ray photoconductor using amorphous selenium alloyed with arsenic were fabricated with different concentrations of the arsenic (0.1 wt.%, 0.3wt.%, 0.5wt.%, 1wt.%, 1.5wt.%, 3wt.%, 5wt.%). The seven kind of samples was fabricated with a-Se alloyed with arsenic through vacuum thermal evaporation. We also investigate the arsenic concentration dependence on the device performance in radiation detector. The electric characteristics of radiation detector devices with changing additive ratio of the arsenic is performed by measuring the x-ray induced photocurrent and integrating it over time to find the total charge. The thickness of a-Se is $100{\mu}m$. Bias voltages $3V/{\mu}m$, $6V/{\mu}m$， $9V/{\mu}m$ are applied at the samples. As results, the net charge of a-Se 0.3% As sample is $526.0pC/mR/cm^2$ at $9V/{\mu}m$ bias. The net charge is decreased as with the increasing additive ratio of arsenic.

• 한국환경보건학회지
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• 제47권5호
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• pp.496-503
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• 2021

Background: Considering the expenses of and difficulties in arsenic speciation by high performance liquid chromatography-inductively coupled plasma-mass spectrometry (HPLC-ICP-MS), alternative measurement methods should be useful, especially for large-scale research and projects. Objectives: A measurement method was developed for arsenic speciation using HPLC-atomic fluorescence spectrometry (HPLC-AFS) as an alternative to HPLC-ICP-MS. Methods: Total arsenic and toxic arsenic species in some seafoods were determined by atomic absorption spectrometry coupled with hydride vapor generation (AAS-HVG) and HPLC-AFS, respectively. Recovery rate of arsenic species in seafood was evaluated by ultra sonication, microwave and enzyme (pepsin) for the optimal extraction method. Results: Limits of detection of HPLC-AFS for As³⁺, dimethylarsinate (DMA), monomethylarsonate (MMA) and As⁵⁺ were 0.39, 0.53, 0.60 and 0.64 ㎍/L, respectively. The average accuracy ranged from 97.5 to 108.7%, and the coefficient of variation was in the range of 1.2~16.7%. As³⁺, DMA, MMA and As⁵⁺ were detected in kelp, the sum of toxic arsenic in kelp was 40.4 mg/kg. As³⁺, DMA, MMA and As⁵⁺ were not detected in shrimp and squid, but total arsenic (iAS and oAS) content in shrimp and squid analyzed by AAS-HVG were 18.1 and 24.7 mg/kg, respectively. Conclusions: HPLC-AFS was recommendable for the quantitative analysis method of arsenic species. As toxic arsenic species are detected in seaweeds, further researches are needed for the contribution degree of seafood in arsenic exposure.

• 자원환경지질
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• 제38권5호
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• pp.599-606
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• 2005

전 세계적으로 수많은 나라의 지하수에 용존 되어있는 비소는 매우 독성이 강한 오염물질이다. 이로 인해서 지하수에 있는 비소를 제거하기 위한 수많은 처리기술들이 개발되고 있다. 미국 환경청에서는 비소를 처리하기 위한 가장 적합한 기술로써 여러 가지의 기술들을 추천하고 있다. 미국 환경청의 분류를 기준으로 비소처리기술은 침전, 멤브레인, 이온교환 및 흡착의 네 가지 처리기술로 나눌 수 있다. 미국에서 최근 $50{\mu}g/L$에서 $10{\mu}g/L$로의 비소 음용수 기준의 개정은 비소오염지하수에 있는 비소를 제거하기 위한 기술의 선택과 적용에 많은 영향을 주고 있다. 침전기술은 비소처리를 위해서 가장 많이 이용되는 기술로 대규모 수처리 설비로 비소를 처리하는데 적용할 수 있는 있지만, 멤브레인, 이온교환 및 흡착기술은 소규모 수처리 시설에 사용된다 최근에 미국과 유럽에서는 설치비와 유지비가 적고 운전이 간편한 흡착기술을 이용한 소규모 비소처리 시설에 많은 관심을 가지고 있는 추세이다 비소로 오염된 지하수를 처리하기 위한 처리기술들의 원리와 비소제거에 영향을 미치는 인자 및 실제 처리시설들의 비소처리효율을 본 논문에서 소개하고자 한다.

• Korean Chemical Engineering Research
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• 제52권5호
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• pp.620-626
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• 2014

The main focus of this study was the evaluation of arsenic concentration in the ground water of Lahore at different depth and application of different mitigation techniques for arsenic removal. Twenty four hours of solar oxidation gives 90% of arsenic removal as compared to 8 hr. or 16 hr. Among oxides, calcium oxide gives 96% of As removal as compared to 93% by lanthanum oxide. Arsenic removal efficiency was up to 97% by ferric chloride, whereas 95% by alum. Activated alumina showed 99% removal as compared to 97% and 95% removal with bauxite and charcoal, respectively. Elemental analysis of adsorbents showed that the presence of phosphate and silica can cause a reduction of arsenic removal efficiency by activated alumina, bauxite and charcoal. This study has laid a foundation for further research on arsenic in the city of Lahore and has also provided suitable techniques for arsenic removal.

• Environmental Analysis Health and Toxicology
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• 제21권1호
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• pp.1-11
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• 2006

Arsenic is a ubiquitous element found in several forms in environment. Although certain foods, such as marine fish, contain substantial levels of organic arsenic forms, they are relatively low in toxicity compared to inorganic forms. In contrast, arsenic in drinking water is predominantly inorganic and very toxic. Chronic ingestion of arsenic-contaminated drinking water is therefore the major pathway posing potential risk to human health. World populations are exposed to low to moderate levels of arsenic of parts per billion (ppb) to thousands of ppb. When exposed to human, it could metabolize into monomethylarsonous acid ($MMA^{III}$) and dimethylarsinous acid ($DMA^{III}$) which are highly toxic. Lots of stuides have been recently focused how $MMA^{III}\;and\;DMA^{III}$ induce toxic insults in various target tissues. Epidemiological studies revealed that chronic arsenic exposure caused cancer, cardiovascular diseases, and diabetes etc. In this review, the current understanding of arsenic on health effects will be discussed.

• Bulletin of the Korean Chemical Society
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• 제34권8호
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• pp.2358-2366
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• 2013

Iron oxide (ferrihydrite, hematite, and magnetite) coated silica gels were prepared using a low-cost, easily-scalable and straightforward method as the adsorbent material for arsenic removal application. Adsorption of the anionic form of arsenic oxyacids, arsenite ($AsO^{2-}$) and arsenate ($AsO{_4}^{3-}$), onto hematite coated silica gel was fitted against non-linear 3-parameter-model Sips isotherm and 2-parameter-model Langmuir and Freundlich isotherm. Adsorption kinetics of arsenic could be well described by pseudo-second-order kinetic model and value of adsorption energy derived from non-linear Dubinin-Radushkevich isotherm suggests chemical adsorption. Although arsenic adsorption process was not affected by the presence of sulfate, chloride, and nitrate anions, as expected, bicarbonate and silicate gave moderate negative effects while the presence of phosphate anions significantly inhibited adsorption process of both arsenite and arsenate. When the actual efficiency to remove arsenic was tested against 1 L of artificial arsenic-contaminated groundwater (0.6 mg/L) in the presence competing anions, the reasonable amount (20 g) of hematite coated silica gel could reduce arsenic concentration to below the WHO permissible safety limit of drinking water of $10{\mu}g/L$ without adjusting pH and temperature, which would be highly advantageous for practical field application.