Title : MCM-41 as a potential mesoporous reference material for characterizing multi textural properties
Abstract:
Mobil Composition of Matter, MCM-41, associated with large surface area (SA) and mesopore-scale pore sizes, finds extensive applications in catalysis, adsorption, separation, sensor, hybrid optics, biomedical devices and drug delivery etc. Simple structure and elegant synthesis procedure of MCM-41 offers it as the most suitable model mesoporous adsorbent available for studying the fundamental features of adsorption such as the effects of pore size, hysteresis, etc., owing to its relatively uniform cylindrical/hexagonal pore channels. The cylindrical pore structure and high degree of pore symmetry associated with MCM-41 merit it as a representative mesoporous material. It is observed that the mesopores of the mesoporous materials used as support in heterogeneous catalyst have potential to act effectively as nanophase reactors, permitting free ingress of reactants and egress of products that have cross-sections smaller than the diameter of the pores. These specific mesoporous concerns of MCM-41 led us to carry out investigations on it for developing it`s standard reference material. There are very few reference materials for analysing the textural properties of the mesoporous material like, activated nanoporous carbons with BET surface area of 550±5 m2/g and 1396±24 m2/g. The BAM is the producers and suppliers of reference standard for pore size analysis. However to the best of our knowledge there is no reference material available/ developed with a potential to analyze multi-properties like SA, pore volume (PV), pore diameter (PD) and wall thickness (WT) by using a single reference material standard. Investigations for the first time were performed by us towards the development of a standard of MCM-41 material associated with high SA, as a reference material to analyze multi-textural properties like SA, PV, PD and WT by using a single reference material of MCM41. Surface area and pore size analyzer need standard reference materials for calibration. MCM41 was elegantly synthesised and thoroughly characterised and subjected for regular time interval analysis of the textural and structural characteristics by nitrogen sorption and PXRD techniques respectively. MCM-41was stored (i) in the glove box and (ii) at ambient atmospheric conditions. The samples stored both ways, demonstrated that this high surface area material is effectively durable and stable for the long analyzed period of one year. The performance of the durability and stability of MCM-41 being almost identical for the samples stored in above two conditions suggested that the storing conditions do not have much effect provided the atmosphere over the sample is dry. No significant change in the values of SA, PV, PD and WT occurred during the long time analysis of one year. This high surface area mesoporous material MCM-41 has shown its promising potential to act effectively as being single reference material to analyse multi textural properties. In line of above the present talk will discourse the findings of the investigations on the development of MCM41 as potential reference material, focussing on its durability, stability, characterisation and associated applications.
