• 한국환경과학회지
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• 제24권9호
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• pp.1189-1197
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• 2015

The aim of this study was to investigate the nutrient removal using Mg-Sericite flocculant in the dyeing wastewater. Mg-Sericite flocculant was removed successfully > 98% of the Color, SS. COD and BOD in the dyeing wastewater at the following optimal Mg-Sericite dosage: 100 mg/L for Colour and SS, 300 mg/L for BOD and COD. The removal of TN and TP was obtained 92.00% with 50 mg/L and 87.80% with 100 mg/L Mg-Sericite dosage, respectively. These results was indicated that the amount of 0.79~1.31, 0.22~0.37, 0.5 and 0.16 mg/L Mg-Sericite was necessary for 1 mg/L removal BOD, COD, TN and TP, respectively. The biopolymer, Mg-Sericite, can be a promising flocculants due to its high efficiency and low dose requirements. In addition, Mg-Sericite does not contaminate treated wastewater, which can be recycled to reduce not only the cost and the demand for water but also the extra operational costs for reusing wastewater. This flocculation method is helpful to lower the wastewater treatment cost.

• 한국물환경학회지
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• 제31권6호
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• pp.625-631
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• 2015

In this study, low cost bio-flocculants, chitosan, cationic starch and Mg-sericite, were used as a flocculant to harvest freshwater microalgae, Chlorella vulgaris. Chitosan, cationic starch and Mg-sericite separated successfully >98% of C. vulgaris at following optimal parameters: 90 mg/L chitosan at pH 6-7, 70 mg/L cationic starch at pH 9-10 and 50 mg/L Mg-sericite at pH 4-5. A relatively high correlation coefficient (R²) of 0.9993 for chitosan, 0.9971 for catonic starch and 0.9924 for Mg-sericite was obtained. The investigated flocculants amount increased linearly with increasing the microalgae amount. The biopolymer, Mg-sericite, was more effective than that of other investigated flocculants. These results indicated that a bio-flocculants, chitosan, cationic starch and Mg-sericite, could prove to be an effective flocculant for economical production of microalgae biomass. In addition, Mg-sericite was more effective comparing to the other investigated flocculants.

• 한국물환경학회지
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• 제31권3호
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• pp.328-333
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• 2015

In this study, Mg-Sericite was used as a flocculant to harvest freshwater microalgae, Chlorella. vulgaris. Mg-Sericite separated successfully >95% of the C. vulgaris at the following optimal parameters: Mg/Si mol ratio 1.25 to 1.50, mixing time of 20 min and settling time of 20 min. The harvesting efficiency was pH dependent. The highest harvesting efficiency ($99{\pm}0.3%$) was obtained at Mg/Si mol ratio 1.5 and pH 9 to 11. These results indicated that a biopolymer, Mg-Sericite, can be a promising flocculant due to its high efficiency, low dose requirements, short mixing and settling times. This harvesting method is helpful to lower the production cost of algae for biodiesel.

• 공업화학
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• 제29권5호
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• pp.571-580
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• 2018

본 연구에서는 수용액에서 Pb(II)를 흡착 제거하기 위하여 커피찌꺼기(spent coffee grounds; SCG)와 점토광물인 견운모(sericite)를 혼합하여 복합흡착제(SS)를 제조하였다. FT-IR 분석결과 SS의 주요 관능기는 O-H, C=O와 C-N 그룹이었다. SS의 비표면적, 기공직경 그리고 양이온 치환 용량은 SCG와 sericite보다 크고, 높았다. SS 흡착제 제조를 위한 최적의 조건은 소성온도 $300^{\circ}C$, SCG : sericite 비율 8 : 2, 입자의 크기는 0.3 mm이었다. SS 흡착제를 이용하여 Pb(II)를 제거하기 위한 실험에서는 Langmuir 흡착식이 Freundlich보다 적합하였으며, Langmuir 등온흡착식에 의한 Pb(II)의 최대 흡착용량은 44.42 mg/g이었다. 또한, 열역학 분석에 의하면 SS 흡착제를 이용한 Pb(II)의 흡착 공정은 물리적인 흡착이었으며, 자연적인 발열반응이었다. SS 흡착제의 흡착-탈착 실험에서는 88-92%를 회수할 수 있었으나, 탈착 횟수가 증가할수록 SS 흡착제의 활성사이트는 감소하였다. 위의 실험결과 SS 흡착제는 전처리 없이 저렴하고, 효율적으로 Pb(II)를 수용액에서 흡착 제거할 수 있다.

• 한국광물학회지
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• 제11권2호
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• pp.69-84
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• 1998

The Daehyun sericite deposit in socheon-myun, Bongwha-gun, Kyungsangbuk-do, Korea, has been formed by the hydrothermal alteration of the Hongjesa granite of Precambrian age, leaving the muscovite granite between ore body and the Hongjesa granite as the wall rock alteration zone. The process of sericitization of granitic rock as well as chemistry and structures of sericites were studied using polarizing microscope, X-ray diffractometer (XRD), electron probe microanalyzer (EPMA) and high resolution transmission electron microscope (HRTEM). There are two genetic types of sericites having different chemistry and structure. The early sericite is of 2M1 polytype and has octahedral composition close to muscovite. It has been formed from the primary muscovite, tourmaline and quartz under a relatively high temperature. The late sericite is of 1M, 2M1 and 3T polytypes and has phengitic composition. It has been formed form feldspar, biotite, muscovite and tourmaline under a relatively low temperature. Chemical analyses show t, the early sericite has less Mg+FeT content and lower Si/AlIV ratio in tetrahedral site than the late sericite.

• Environmental Engineering Research
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• 제22권3호
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• pp.312-319
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• 2017

The treatment of dyeing wastewater is not easy because dyes are mainly aromatic, heterocyclic compounds. The most effective technologies and methods to treat dyeing wastewater are costly and involve materials that are difficult to regenerate after use. Therefore, it is necessary to develop cost-effective, eco-friendly technologies to treat dyeing wastewater. The aim of this study was to investigate the removal of sulfur blue 11 (CI 53235) anionic dye using methyl esterified sericite (ME-sericite) adsorbents in an aqueous solution. The results are discussed in terms of the ME-sericite particle size, temperature, pH value and initial sorption rate according to the initial sulfur blue concentration. In addition, we analyzed the adsorption kinetics using a Pseudo-second-order model with the desorption and reusability. The methyl esterification caused a considerable increase in the specific surface area from 4.45 to $17.62m^2/g$. The ME-sericite adsorbents successfully removed > 98% of the sulfur dye in the aqueous solution. For the adsorption of 1 mg of sulfur dye, approximately 4.6 to 6.6 g/L ME-sericite were required. The desorption process was carried out by mixing a NaOH eluent to desorb 90.56% of the sulfur dye with 2 h of contact time. Thus, the ME-sericite is a promising adsorbent to treat dyeing wastewater due to its low dose requirement, high removal efficiency and inexpensive material.

• Environmental Engineering Research
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• 제11권6호
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• pp.303-310
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• 2006

The aim of this study is to assess the applicability of sericite in wastewater treatment particularly the removal of two important heavy metal toxic ions viz., Cu(II) and Pb(II) from aqueous solutions. The batch type experiments showed that sericite is found to be one of useful natural sorbent for the removal of these two cations from aqueous solutions and it is also to be observed that with the increase in sorptive concentration amount of metal uptake increases and the concentration dependence data obtained are fitted well for the Langmuir adsorption isotherm rather than Freundlich adsorption model. Further, the Langmuir monolayer adsorption capacity is found to be $1.674\;mg\;g^{-1}$ for Cu(II) and $4.697\;mg\;g^{-1}$ for Pb(II). Kinetic studies enabled, an apparent equilibria can be achieved between soild/solution interface within ca 10 mins for Cu(II) and ca 90 mins for Pb(II). Moreover, the removal behavior of sericite for these two metal ions is greatly influenced by solution pH.

• 청정기술
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• 제19권3호
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• pp.347-350
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• 2013

견운모에 흡착된 니켈이온의 탈착과 재생특성에 관한 연구가 최적의 탈착제로서 선정된 $HNO_3$를 이용하여 수행되어졌다. 견운모에 흡착된 니켈이온의 탈리는 주사전자현미경과 에너지 분산형 X선 분광기에 의해서 확인 되어졌다. 20 mM의 농도에서 니켈이온의 탈착율은 100%였다. 또한, 투입된 흡착제의 양과 탈착제의 부피로서 정의되는 S/L비가 1.0내에서는 니켈이온은 완전히 탈착 되어졌으며 탈착 공정은 60분내에 빨리 일어났다. 마지막으로 재사용된 견운모를 이용하였을 때 4회까지는 니켈이온의 탈착율이 일정하게 유지되었다.

• Korean Journal of Chemical Engineering
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• 제35권11호
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• pp.2198-2206
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• 2018

We addressed the development of a novel, low-cost, and high-efficient material from hybrid materials, known as microcapsules. Microcapsules are a composite adsorbent made of a mixture of tannin, sericite and chitosan. The FT-IR analysis showed that the microcapsules contain hydroxyl, carboxyl, carbonyl, and amino groups, which play an important role in the adsorption of heavy metals. The microcapsules were able to remove 99% of Pb(II) in 30 min, and obtained a removal efficiency of more than (13-50)%, compared with the single adsorbents of tannin, chitosan, and sericite. In adsorption kinetic analysis, pseudo-second-order adsorption was more suitable than pseudo-first-order adsorption, and chemical adsorption did not limit the adsorption rate of Pb(II) ion. In isothermal adsorption, Langmuir adsorption was more suitable than Freundlich adsorption, and the maximum Langmuir adsorption capacity was 167.82 (mg/g). Furthermore, desorption and reusability studies, as well as the applicability of the material for wastewater treatment, demonstrated that microcapsules offer a promising hybrid material for the efficient removal of significant water pollutants, i.e., Pb(II) from aqueous solutions.

• 자원환경지질
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• 제30권4호
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• pp.279-289
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• 1997

Dark to pale green-colored, Cr-bearing sericites from hydrothermal alteration zone of the Narim gold deposit were investigated mineralogically and geochemically. The alteration zone is composed mineralogically of quartz, carbonate minerals and green sericite with minor amounts of chlorite, barite and sulfide minerals (pyrite, sphalerite, galena). The zone is enriched in As (967 to 1520 ppm), Cu (31 to 289 ppm), Ni (1027 to 1205 ppm), Pb (0.20 to 1.24 wt.%) and Zn (1.03 to 1.07 wt. %) compared with fresh rocks such as granitic gneiss, porphyritic biotite granite and basic dyke. The Cr, probably the chromophore element, is highly enriched in the alteration zone (1140 to 1500 ppm), host granitic gneiss (1200 ppm) and porphyritic biotite granite (1200 ppm). Occurrence and grain size of sericite are diverse, but most of the Cr-bearing sericites (150 to $200{\mu}m$ long and 20 to $30{\mu}m$ wide) occur along the boundaries between ore veins and host rocks (especially basic dyke and granitic gneiss). X-ray diffraction data of the sericite show its monoclinic form with unit-cell parameters of $a=5.202{\AA}$, $b=8.994{\AA}$, $c=20.103{\AA}$, ${\beta}=95.746^{\circ}$ and $V=935.83{\AA}^3$, which are similar with the normal 2M1-type muscovite. Representative chemical formula of the sericite is ($K_{1.54}Ca_{0.03}Na_{0.01}$)($Al_{3.42}Mg_{0.38}Cr_{0.14}Fe_{0.06}V_{0.02}$)($Si_{6.69}Al_{1.31}$)$O_{20}(OH)_4$. The Cr content increases with decrease of the octahedral Al content, and ranges from 0.36 to 2.58 wt.%. DTA and TG curves of the sericite show endothermic peaks at $342^{\circ}$ to $510^{\circ}$, $716^{\circ}$ to $853^{\circ}$ and $1021^{\circ}C$, which are due to the expulsion of hydroxyl group. The total weight loss by heating is measured to be about 8.8 wt. %, especially at $730^{\circ}C$. Infrared absorption experiments of the sericite show broad absorption band due to the O-H bond stretching vibration near the $3625cm^{-1}$, coupled with the 825 and $750cm^{-1}$ doublet. The vibration bands related with the H-O-Al and Si-O-Al bonds occur at $1030cm^{-1}$ and 500 to $700cm^{-1}$, respectively. Based on paragonite content of the sericite, the formation temperature of the Narim gold deposit is calculated to be $220{\pm}10^{\circ}C$.