SEM-EDS 분석에 의한 KH2PO4와 Na2SiO3로 피복된 황철석 표면 특성 연구

Abstract

본 연구는 황철석 표면의 불활성 피막 형성의 완성도와 표면 특성의 관련성을 파악하기 위하여 수행되었다. 결정면과 임의의 노출면에서의 피복효과의 차이를 비교하기 위하여 작은 입자들이 군집상태로 산출된 황철석과 입방체 형태의 황철석 시료의 표면을 연마한 후 SEM-EDS 분석을 수행하였다. 작은 입자들이 군집상태로 산출된 황철석에 0.05M의 KH2PO4로 피복하였을 때 피복이 되는 입자들과 피복이 되지 않는 입자들이 존재하였다. 이는 재현 실험을 통해서도 확인되었고, Na2SiO2로 제조한 피복제에서도 동일한 결과를 얻었다. 노출면이 결정면으로 판단되는 입방체의 황철석의 경우 다양한 농도의 KH2PO4(0.05M, 0.1M, 0.2M)와 H2O2(0.05M, 0.1M, 0.2M), pH 조건의 변화(6, 7, 8), Fe(Ⅱ) 0.3mM과 0.6mM의 추가 등에서 피복을 수행하였으나 모든 결정면에서 피복이 되지 않는 것을 확인하였다. 표면의 거칠기에 의한 피복효과의 차이점도 없는 것으로 확인되었다. 하지만 결정면이 아닌 입방체의 황철석을 가공하여 만든 임의의 일반 노출면에서의 경우 피복이 이루어졌음을 확인하였다.|This study was conducted to evaluate the relationship between the formation of inert film formed on the pyrite surface and surface property of it. Different types of surfaces, one of which is crystal plane and the other is arbitrarily exposed surface, were chosen. The surfaces of pyrite occurring as assemblage of small particles and of cubic pyrites were treated by coating materials and analyzed by SEM-EDS. When assemblage of small particles was treated by 0.05M KH2PO4, some particles were coated and some were not. The repeated treatment showed the same results. And when Na2SiO2 was applied, the exactly same results were obtained. The cubic pyrite, the exposed surfaces are believed to be its own crystal planes, was treated under various conditions : varying concentrations of KH2PO4(0.05M, 0.1M and 0.2M) and H2O2(0.05M, 0.1M and 0.2M), changing pH(6, 7 and 8) and adding Fe(Ⅱ)(0.3mM and 0.6mM). However the results showed crystal planes were not coated in any condition. And also unevenness of surfaces did not affect the formation of inert film. However when arbitrarily exposed surface revealed by grinding were treated, the inert film were formed.; This study was conducted to evaluate the relationship between the formation of inert film formed on the pyrite surface and surface property of it. Different types of surfaces, one of which is crystal plane and the other is arbitrarily exposed surface, were chosen. The surfaces of pyrite occurring as assemblage of small particles and of cubic pyrites were treated by coating materials and analyzed by SEM-EDS. When assemblage of small particles was treated by 0.05M KH2PO4, some particles were coated and some were not. The repeated treatment showed the same results. And when Na2SiO2 was applied, the exactly same results were obtained. The cubic pyrite, the exposed surfaces are believed to be its own crystal planes, was treated under various conditions : varying concentrations of KH2PO4(0.05M, 0.1M and 0.2M) and H2O2(0.05M, 0.1M and 0.2M), changing pH(6, 7 and 8) and adding Fe(Ⅱ)(0.3mM and 0.6mM). However the results showed crystal planes were not coated in any condition. And also unevenness of surfaces did not affect the formation of inert film. However when arbitrarily exposed surface revealed by grinding were treated, the inert film were formed.