Search Results

Now showing 1 - 4 of 4

Some of the metrics are blocked by your
consent settings
1H NMR-based machine learning methods for rapid authentication and composition profiling of crude palm oil
(2026-09-01)
Nggofur, Abdul
;
Sueviriyapan, Natthapong
;
Nuntawong, Noppadon
;
Sutthiumporn, Ketsada
;
Sooknoi, Tawan
A rapid analytical workflow for determining geographical origin and predicting fatty acid composition of crude palm oil (CPO) was developed using 1H NMR, GC-FID, and machine learning. Analyzing CPO samples from Indonesia, Malaysia, the Philippines, and Thailand using unsupervised fingerprinting with principal component analysis (PCA), t-distributed stochastic neighbor embedding (t-SNE), and uniform manifold approximation and projection (UMAP) revealed partial origin-based grouping. Supervised classification, validated via leave-one-out cross-validation (LOOCV) and uncertainty quantification (UQ), reliably discriminated the origins above random chance. Additionally, partial least squares regression (PLSR) accurately predicted oleic, linoleic and myristic acid levels measured by GC-FID, whereas the accuracy decreased for lauric, stearic and palmitic acids. PLSR reliability was rigorously validated using latent variable selection and permutation testing to rule out random correlations. Overall, this integrated 1H NMR and machine learning approach offers a rapid tool for CPO geographical traceability and compositional evaluation, demonstrating its potential for industrial quality control.
Some of the metrics are blocked by your
consent settings
Water-assisted ketonization of methyl palmitate to palmitone over metal incorporated TiO2 catalysts
(2024-05-28)
Pittayatornkul, Jetsadagorn
;
Maluangnont, Tosapol
;
Jongpatiwut, Siriporn
;
Praserthdam, Piyasan
;
Ogawa, Makoto
Ketonization of methyl palmitate to palmitone, a bio-lube precursor, was investigated over noble metal (Pt, Ru, and Pd) incorporated TiO<inf>2</inf> catalysts in the presence of water under an atmospheric H<inf>2</inf>/N<inf>2</inf> flow. Methyl palmitate underwent hydrolysis to palmitic acid that ketonized to palmitone over Lewis Ti3+ sites. The water co-feeding also suppressed hydrodeoxygenation of methyl palmitate and palmitone cracking leading to high palmitone selectivity. The incorporated metals facilitated H<inf>2</inf> dissociation/spillover on TiO<inf>2</inf> which generated more Lewis Ti3+ sites for higher ketonization activity. At 400 °C, 0.5Pd/TiO<inf>2</inf> provided ∼90% conversion with >85% palmitone selectivity and >25 h stability, due to its efficient H<inf>2</inf> dissociation/spillover to continually recover Lewis Ti3+ sites. Meanwhile 0.5Pt/TiO<inf>2</inf> promoted excessive hydrodeoxygenation, leading to the deactivation from CO poisoning at the metallic Pt sites. The findings of this study offer a sustainable approach for the selective production of bio-lube precursors from renewable fatty acid methyl esters.
Some of the metrics are blocked by your
consent settings
Generation of reductive Zn species over Zn/HZSM–5 catalysts for n–pentane aromatization
(2016-09-05)
Tamiyakul, Sikarin
;
Sooknoi, Tawan
;
Lobban, Lance L.
;
Jongpatiwut, Siriporn
The effects of hydrogen treatment on Zn/HZSM–5 catalysts to the evolution of zinc species and their activity in n-pentane aromatization were studied. By heating Zn/HZSM–5 catalysts under inert atmosphere, most of zinc species appeared as (ZnOH)+. The XPS and IPA–TPD results showed that using H<inf>2</inf> as a treatment gas, the hydrodehydroxylation of (ZnOH)+ generated (ZnH)+ species with the recovery of some Brønsted acid sites. It was found that under the hydrogen atmosphere, the H<inf>2</inf> molecule was dissociated on this Zn species and generated the H<inf>2</inf>-chemisorbed Zn species. Compared with HZSM-5 catalyst, the presence of (ZnOH)+ species improved the aromatics selectivity from 11% to 22%. Nevertheless, after pre-treating Zn/HZSM–5 with H<inf>2</inf>, the formation of H<inf>2</inf>-chemisorbed Zn species remarkably increased the BTX aromatics selectivity to 31%. It was found that the H<inf>2</inf>-chemisorbed Zn species was not stable in the absence of H<inf>2</inf> however it could be regenerated upon H<inf>2</inf> treatment.
Some of the metrics are blocked by your
consent settings
Effect of extra-framework cesium on the deoxygenation of methylester over CsNaX zeolites
(2011-12-15)
Danuthai, Tanate
;
Sooknoi, Tawan
;
Jongpatiwut, Siriporn
;
Rirksomboon, Thirasak
;
Osuwan, Somchai
The deoxygenation of methyl octanoate has been investigated over Cs-containing NaX zeolite catalysts at atmospheric pressure with He carrier gas and methanol as a co-feed. By varying the preparation procedures, different amounts of extra-framework Cs were left on the catalyst. The presence of extra-framework Cs affects the acid-basic characteristics of the catalysts and consequently their activity, stability, and particularly the product selectivity. That is, when the amount of extra-framework Cs increases, the corresponding increase in basicity enhances decarbonylation activity as well as catalyst stability. In this case, the deoxygenation of methyl octanoate on CsNaX catalysts was found to yield heptenes and hexenes as main products via surface decomposition of octanoate-like species. When the amount of extra-framework Cs was reduced, the hexene yield readily increased. The enhancement in hexene production can be ascribed to both, a decreased basicity that reduces decarbonylation and to a greater space available within the zeolite cavity for formation of a rather bulky cyclic-like intermediate that leads to hexene. In addition, weakly acidic sites, generated after the excess Cs was removed, resulted in relatively higher yield of inner-olefin product. When Cs was not present in the catalyst (i.e., NaX), other products such as aromatics and coupling compounds were observed. These compounds are less desirable for transportation fuel applications. © 2011 Elsevier B.V. All rights reserved.

KMITL

Browse

Filters

Settings

Sort By

Results per page

Search Results