Cordierite Honeycomb Monoliths Coated with Zirconia and Its Modified Forms for Biodiesel Synthesis from Pongamia glabra

Abstract

This study investigates the use of cordierite honeycomb monoliths coated with solid acids such as zirconia, Mo(VI)/ZrO2 and Pt‐SO42−/ZrO2 and solid bases like zirconia–calcia, zirconia–magnesia mixed oxides in the synthesis of biodiesel from oil (PG‐oil). Solid acids were used for the esterification of free fatty acids in PG‐oil with methanol to reduce the percentage of free fatty acids in the oil followed by transesterification of PG‐oil over solid bases to synthesize biodiesel. The oxide catalysts were coated on honeycombs by an impregnation technique and characterized for their surface acidity/basicity, crystallinity and morphology. The effect of the molar ratio of PG‐oil/methanol in esterification and transesterification was studied. Reactivation and reusability of both solid acid and solid base catalysts was investigated. The catalysts were also prepared in their powder forms and their activity was compared with that of honeycomb coated forms. A twofold increase in the yield of biodiesel was obtained when the catalysts were used in honeycomb coated forms. The results revealed that the honeycombs coated with mixed oxides such as zirconia–calcia and zirconia–magnesia were economical, efficient and eco‐friendly (3e concept) for biodiesel production with ~95 % yield.

Vapor phase synthesis of glycerol carbonate over honeycomb monolith coated with zirconia based base catalysts

“…Interestingly, no reflections related to bare honeycomb were observed in the PXRD patterns of Z, MZ, CZ and BZ indicating that the active catalysts are effectively coated on the bare HM. Similar observations have been made by Shyamsundar et al (2015). …”

“…The resulting solution was coated on a HM by 'dip & dry' method (Shyamsundar et al, 2015) in a furnace preheated to 400 o C. Dip and dry steps were repeated for 6-8 times till ~0.15 g of ZrO 2 is coated on the HM. …”

“…The reaction products obtained after the reaction were analyzed by gas chromatograph (Mayura) fitted with a column (10% SE-30 chromosorb w-AW, 3 m x 1/800) coupled with a FID detector using N 2 as the carrier gas and preheating time of 90 min (Shyamsundar et al, 2015). The reaction products were also analyzed qualitatively by GC-MS (Varian).…”

“…But, honeycomb monoliths (HMs) coated with solid acid/base catalysts have not been explored much in the field of organic fine chemical synthesis. Though, a limited literature could be found on the application of HMs coated with solid acids in liquid phase reactions (Shyamsundar et al, 2015), no literature could be found on the application of such HMs for the synthesis of fine chemicals via vapor phase.…”

Catalytic Synthesis of Levulinate Esters over Zirconia and its Modified Forms Coated on Honeycomb Monoliths: Green Synthesis

“…Preparation of catalytic material in honeycomb coated form: Solid acids such as ZrO2, 5 % Mo(VI)/ZrO2 (MZ) and 5 % W(VI)/ZrO2 (WZ) were coated on different honeycomb monoliths by using 'dip and dry' method [16]. Before coating the active catalysts, the honeycomb monolith was wash coated with zirconia in order to increase the surface area and to have a support material which has a better interaction with the active catalyst [17].…”