Synthesis and Characterization of Crystalline NaY-Zeolite from Belitung Kaolin as Catalyst for n-Hexadecane Cracking

Abstract

Crystalline sodium Y (NaY) zeolite has been synthesized using alternative natural source of aluminate and silicate, extracted from natural Belitung kaolin. Prior to use, the natural kaolin was pretreated to obtain fragmented metakaolin and extracted silica. Synthesis was conducted with the addition of NaY gel (two types of NaY seeds were used, prepared from colloidal sillica or sodium silica water) using hydrothermal method for 21 h at 100 °C. The characterization on the as-synthesized zeolites confirmed that the one prepared using colloidal silica-seed has closer structure similarity to NaY zeolite that was synthesized using pro analysis silicate and aluminate sources. Thus, the rest of the synthesis of NaY was carried out using colloidal silica-NaY seed. The NaY zeolites then were converted to HY, through ammonium-exchange followed by calcination, to be tested as cracking catalysts using n-hexadecane as a probe molecule. It shows that HY from metakaolin and extracted silica gives high performance, i.e., n-hexadecane conversion of 58%–64%, also C5-C12 percentage yield and selectivity of 56%–62% and 98%. This work has shown the potential to utilize kaolin as alternative silicate aluminate sources for crystalline zeolite synthesis and to obtain inexpensive and environmentally friendly catalyst materials.

The new challenge of partial oxidation of methane over Fe2O3/NaY and Fe3O4/NaY heterogeneous catalysts

“…The SEM image in Figure 3 shows the morphology of the assynthesized NaY zeolite that exhibits sharp-edged cuboid-octahedral crystal habits, which is the characteristic of NaY zeolite [30,31,32]. It also has smooth surfaces, indicative of high crystalline as also supported by the well-defined XRD pattern.…”

Natural Aluminosilicate-based Y Zeolite for Catalytic Cracking of n-Hexadecane

“…The shape of 29 Si NMR peaks observed in NaY-1 was broader than that observed in NaY prepared from kaolin only as silica source. Furthermore, the ) were also created, and the intensity was higher than a similar peak that appeared in NaY reported in Crystals [9]. Overall, the 29 Si and 27 Al NMR data explained that the structure of the as-synthesized NaY already possessed the framework of Faujasite (FAU) [21], although the crystallinity still needs to be improved.…”

“…Examples of zeolite synthesis methods use natural/wastes, such as polish coal fly ash [6], diatomite [7], and rice husk [8]. Our previous work published in Crystals [9] reported our attempt to synthesize NaY using kaolin. Currently, we are attempting to use natural zeolite as source together with kaolin.…”

“…In this research, NaY zeolite was synthesized using Bayat-Klaten natural zeolite as a source of silica and alumina. This zeolite was synthesized to compare the efficiency of zeolites from the natural mineral Bayat-Klaten zeolite with those from extracted silica from kaolin as reported in a previous study [9].…”

Alkaline Activation of Kaolin Group Minerals

“…or natural clays, for instance, kaolinite and halloysite. Using those natural minerals for the synthesis of zeolite and zeolite-geopolymer hybrid bulk materials is a topical issue [3,5,6]. Despite the fact that both kaolinite (Al 2 Si 2 O 5 (OH) 4 ) and halloysite (Al 2 Si 2 O 5 (OH) 4 •2H 2 O) have similar compositions [7], their reactivity is different.…”