• 한국광물학회지
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• 제22권4호
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• pp.307-312
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• 2009

제주도의 화산쇄설성 퇴적암인 신양리층에서 산출되는 motukoreaite와 quintinite-3T를 보고한다. 두 광물은 Mg-Al 층상복수산화물로서 현무암 유리질 입자 사이를 충전하는 극미립판상 입자들의 구상 또는 포도상 집합체로 산출된다. Quintinite-3T의 집합체 외각에 motukoreaite의 판상 입자들이 과성장하여 피복하였다. 두 광물의 X선회절자료와 화학조성은 대체로 문헌에 보고된 값들과 유사하지만, motukoreaite의 Mg/Al 비는 보고된 값보다 조금 크다. 전자현미화학 분석 값으로부터 구한 motukoreaite와 quintinite-3T의 구조식은 각각 $Na_{1.6}Ca_{0.1}Mg_{40.7}Al_{20.7}Si_{0.9}(CO_3)_{13.6}(SO_4)_{7.4}(OH)_{108}56H_2O$와 $Mg_{3.7}Al_{1.9}Si_{0.2}(OH)_{12}(CO_3)_{0.8}(SO_4)_{0.2}3H_2O$이다. 두 광물은 얕은 바다에 퇴적된 현무암 유리질 입자들이 해수와 반응하여 생성 되었으며, 해저 환경에서 화산쇄설성 퇴적물의 교결 및 고화작용에 기여하였다.

• Environmental Engineering Research
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• 제19권3호
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• pp.247-253
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• 2014

The aim of this study was to characterize quintinite in fluoride removal from aqueous solutions, using batch experiments. Experimental results showed that the maximum adsorption capacity of fluoride to quintinite was 7.71 mg/g. The adsorption of fluoride to quintinite was not changed at pH 5-9, but decreased considerably in highly acidic (pH < 3) and alkaline (pH > 11) solution conditions. Kinetic model analysis showed that among the three models (pseudo-first-order, pseudo-second-order, and Elovich), the pseudo-second-order model was the most suitable for describing the kinetic data. From the nonlinear regression analysis, the pseudo-second-order parameter values were determined to be $q_e=0.18mg/g$ and $k_2=28.80g/mg/hr$. Equilibrium isotherm model analysis demonstrated that among the three models (Langmuir, Freundlich, and Redlich-Peterson), both the Freundlich and Redlich-Peterson models were suitable for describing the equilibrium data. The model analysis superimposed the Redlich-Peterson model fit on the Freundlich fit. The Freundlich model parameter values were determined from the nonlinear regression to be $K_F=0.20L/g$ and 1/n=0.51. This study demonstrated that quintinite could be used as an adsorbent for the removal of fluoride from aqueous solutions.

• Environmental Engineering Research
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• 제20권1호
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• pp.73-78
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• 2015

The aim of this study was to examine the phosphate (P) removal by quintinite from aqueous solutions. Batch experiments were performed to examine the effects of reaction time, temperature, initial phosphate concentration, initial solution pH and stream water on the phosphate adsorption to quintinite. Kinetic, thermodynamic and equilibrium isotherm models were used to analyze the experimental data. Results showed that the maximum P adsorption capacity was 4.77 mgP/g under given conditions (initial P concentration = 2-20 mgP/L; adsorbent dose = 1.2 g/L; reaction time = 4 hr). Kinetic model analysis showed that the pseudo second-order model was the most suitable for describing the kinetic data. Thermodynamic analysis indicated that phosphate sorption to quintinite increased with increasing temperature from 15 to $45^{\circ}C$, indicating the spontaneous and endothermic nature of sorption process (${\Delta}H^0=487.08\;kJ/mol$; ${\Delta}S^0=1,696.12\;J/(K{\cdot}mol)$; ${\Delta}G^0=-1.67$ to -52.56 kJ/mol). Equilibrium isotherm analysis demonstrated that both Freundlich and Redlich-Peterson models were suitable for describing the equilibrium data. In the pH experiments, the phosphate adsorption to quintinite was not varied at pH 3.0-7.1 (1.50-1.55 mgP/g) but decreased considerably at a highly alkaline solution (0.70 mgP/g at pH 11.0). Results also indicated that under given conditions (initial P concentration=2 mgP/L; adsorbent dose=0.8 g/L; reaction time=4 hr), phosphate removal in the stream water (1.88 mgP/g) was lower than that in the synthetic solution (2.07 mgP/g), possibly due to the presence of anions such as (bi)carbonate and sulfate in the stream water.