Lignin — FTIR-absorptions-toppe og tildelinger

Hurtigt svar

Lignin tildeles normalt ved at lede efter en tilbagevendende klynge af karakteristiske toppe frem for et præcist lærebogsnummer. Tabellen nedenfor viser, hvor litteraturen oftest placerer denne gruppe i FTIR, rangeret efter akkumuleret evidens.

Karakteristiske FTIR-toppe for Lignin

Viser de 30 bedst understøttede toppe ud af 273 i alt for Lignin.

Mulige materialer

Spektrumlogik

En funktionel gruppetildeling bliver mere sikker, når flere forventede bånd optræder sammen. Brug denne side til at finde de bedst understøttede peaks, og bekræft derefter, at den samme prøve udviser et sammenhængende mønster snarere end et enkelt isoleret hit.

Anvendelse i virkeligheden

Disse sider er nyttige til analyse af ukendte materialer, topforklaring i rapporter, polymerfejlfinding og verifikation af, om en kandidatmaterialefamilie er kemisk plausibel.

Almindelige fejl

• Brug af én funktionel-gruppe-side som en komplet materialebedømmelse uden at kontrollere resten af spektret.
• Antager, at det stærkeste bånd altid er det mest diagnostiske.
• At glemme, at forarbejdning, tilsætningsstoffer, ældning og blandinger kan flytte eller udvide forventede toppe.

Verifikationsrådgivning

Brug DSC, GC-MS eller TGA, når flere materialefamilier deler lignende bånd, eller når blandings-effekter gør FTIR-tildelingen usikker.

Litteratur bag disse tildelinger

• 1514 cm⁻¹ tillid 1,0

  “Enzymatic delignification of cm-1 cm-1 this optimized mixture was supported by FTIR studies where peak intensity at 1514 and 1595 corresponding to the aromatic skeletal vibrations of lignin decreased in magnitude after delignification.”

  A strategic laccase mediated lignin degradation of lignocellulosic feedstocks for ethanol production DOI: 10.1016/j.indcrop.2016.08.009
• 1050 cm⁻¹ tillid 1,0

  “These peaks were overlapped with the large and intense For sample L-PS4, the intensity of the -OH groups cm-1 lignin stretching bands at 1050 (Azhar et al.”

  Azhar 等 - 2020 - Lignin-Coated PolystyreneTrichloromethylsilane Ab DOI: 10.17576/jsm-2020-4909-12
• 1240 cm⁻¹ tillid 1,0

  “LLM confirmed rule peak-group candidate”

  Physicochemical characterisation of barley straw treated with sodium hydroxide or urea and its digestibility and in vitro fermentability in ruminants DOI: 10.1038/s41598-022-24738-w
• 1634 cm⁻¹ tillid 1,0

  “cm-1 cm-1 at 1510 could be due to aromatic ring vibrations of lignin [35], and peak at 1634 327 represents the carbonyl group in conjunction with an aromatic ring in lignin [36].”

  Balan 等 - 2021 - Esterification of residual palm oil using solid ac DOI: 10.1016/j.jtice.2012.07.001.
• 3400 cm⁻¹ tillid 1,0

  “The FTIR spectral features of the extractive free enset fiber and stalk (Fig 5) show similar cm-1, cm-1, cm-1, cm-1 cm-1 peaks around 3400 2945 1746 1380 and 1033 which correspond to different functional groups of cellulose, hemicelluloses”

  Characterization of crop residues from false banana /Ensete ventricosum/ in Ethiopia in view of a full-resource valorization DOI: 10.1371/journal.pone.0199422
• 830 cm⁻¹ tillid 1,0

  “The peak around 830 assoAs thesamples from the north side of (denoted with C-H "-N" ciated with bending of syringyl units, also contributed to in the sample name) were irrigated and samples from the eld”

  Bryant 等 - 2023 - Variable lignin structure revealed in Populus leav DOI: 10.1039/d3ra03142j
• 1427 cm⁻¹ tillid 1,0

  “cm-1 characteristic peak at 1735 (acetyl groups in xylan and other nonconjugated carcm-1 cm-1 bonyls), C=O stretch in xylan (hemicelluloses) and the peaks at 1508 and 1427 cm-1 cm-1 show the aromatic skeletal vibration of lignin.”

  n-Heptadecane-Impregnated Wood as a Potential Material for Energy-Saving Buildings DOI: 10.3390/f13122137
• 1500 cm⁻¹ tillid 1,0

  “Significantly, an increase in hemicellulose cm-1 and cellulose peaks around 1700 was determined, while the lignin peak around cm-1 1500 disappeared completely.”

  Can 等 - 2023 - Choline Chloride-Based Deep Eutectic Solvent-Treat DOI: 10.3390/f14030569