TAILIEUCHUNG - Estimating thermal stability of phosphated and phosphated sulfated mesoporous zirconia
Mesoporous phosphated zirconia (m-PZ) and mesoporous phosphated sulfated zirconia (mPSZ) were synthesized through condensation methods using Zr3(PO4)4 and Zr(SO4)2 as precursors, respectively. The precursors, solvents with suitable molar or mass ratios were mixed at 100 oC for 48 hours to obtain the mesoporous channels. An oxophosphate process was used to synthesize the m-PSZ material for improving its thermal stability. Some techniques were used to characterize the materials such as SAXRD, TG-DTA and TEM. | Journal of Science and Technology 54 (6) (2016) 748-754 DOI: ESTIMATING THERMAL STABILITY OF PHOSPHATED AND PHOSPHATED SULFATED MESOPOROUS ZIRCONIA Phong Pham Van1, Khanh Dieu Hong Nguyen2, * 1 2 Vietnam National Oil and Gas Group, 18 Lang Ha Street, Ba Dinh, Hanoi Hanoi University of Science and Technology, 1 Dai Co Viet Street, Hai Ba Trung, Hanoi * Email: dieuhong_bk@ Received: 29 January 2016; Accepted for publication: 15 September 2016 ABSTRACT Mesoporous phosphated zirconia (m-PZ) and mesoporous phosphated sulfated zirconia (mPSZ) were synthesized through condensation methods using Zr3(PO4)4 and Zr(SO4)2 as precursors, respectively. The precursors, solvents with suitable molar or mass ratios were mixed at 100 oC for 48 hours to obtain the mesoporous channels. An oxophosphate process was used to synthesize the m-PSZ material for improving its thermal stability. Some techniques were used to characterize the materials such as SAXRD, TG-DTA and TEM. Keywords: mesoporous, zirconia, oxophosphate, thermal stability. 1. INTRODUCTION The synthesis of MCM-41, a silica with a hexagonal arrangement of cylindrical pores, the sizes of which are adjustable from 2 to 10 nm, and related materials [1] has stimulated a considerable amount of interest in this new class of mesoporous materials. Shortly after its synthesis, different mechanisms were developed to explain the formation of this porous material [2]. The mechanism suggested by Monnier et al. [2] implies the possibility of substituting the silicate with other metal oxides to prepare a wide range of mesostructured oxidic materials. Subsequently, mesostructured surfactant composites of tungsten oxide, antimony oxide, and other metal oxides have been synthesized [3, 4]. However, a major problem of these nonsiliceous materials is the removal of the template: it was neither possible to remove the surfactant by conventional methods like calcination or extraction nor by oxygen .
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