Arni Saleh Ph.D. student, xx cycle

1. Activity Presentation Arni Saleh Ph.D. student, xx cycle e-mail: arni@unige.it arnisaleh@hotmail.com

2. Aromatic compounds from Sugarcane Bagasse

3. Presentation outline • Background • Biomass Pretreatment • Process for extract lignin materials • Lignin extractions • Study of lignin extractions

4. Background • Bagasse material • Renewable resource, economics and environment • What is lignin?

5. BackgroundWhat is Bagasse? • Bagasse material • Cellulose 33-48% • Hemicellulose 19-43% • Lignin 6-32% • Renewable Resource, Economics and Environment Increasing importance is being given to biomass as a renewable and environment friendly resource, which has motivated a great number of economic utilization as starting materials for various bioproduction.

6. Background What is lignin? • Natural lignin composition and structure are unknown. • It is a heterogeneous polymer. • It is made up of three principal monomers.

7. Biomass Pretreatment

8. Biomass Pretreatment Bagasse was first dried in sunlight, then in oven at 105°C, cut into small pieces and stored in desiccator at room temperature. The dried biomass of bagasse was ground using a laboratory mill and screened to prepare 40 mesh powder.

9. Processes for extract lignin materials • Hydrolysis method • Alkaline sugarcane bagasse hydrolysis

10. Dried sugarcane bagasse Grounding and screening to prepare 40 mesh powder Treatment with NaOH in autoclave at 121°C, for 1 h Solid residue Extract Waste a) Filtration with 0.45 mm pore filters b) Acid treatment with H3PO4 (pH 3) c) Filtration with 0.20 mm pore filters HPLC Analysis Extraction of lignin from sugarcane bagasse Hydrolysis method Alkaline sugarcane bagasse hydrolysis

11. Lignin extraction

12. Lignin extraction

13. Study of lignin extractions • Experimental Techniques • The determination of pKa by Uv/Vis Spectroscopy • Study of aggregation by Uv/Vis Spectroscopy

14. Experimental Techniques

15. Uv/Vis Spectroscopy Incident lightIo transmitted light It Beer-Lambert Law is A= cl = log10(Io/It)

16. Results The determination of pKa by Uv/Vis Spectroscopy • A) p-Coumaric acid result data • B) Ferulic acid result data • C) Syringic acid result data • D) Vanillin result data

17. p-Coumaric acid result data Absorbance spectra of p-Coumaric acid, in only solvent distilled water, an environment not resistant to the effect of pH change from 2to 7. Changes of a solution pH cause changes in the electrostatic interactions within the component and the solvent system.

18. p-Coumaric acid result data The effect of pH between 2 and 5, in this range pCA is reversible and the maximum value of absorbance is about pH 3.5; at lmax(310). The reversible points indicated the p-Coumaric acid is pure.

19. Ferulic acid result data From the analysis of the plots Absorbance of pH Titration Curves Ferulic acid at lmax(322) and at lmax(346), the pKa1 and pKa2 values were obtained 4.72, 9.21 respectively.

20. Syringic acid result data From the analysis of pH titration curves at lmax(270), and lmax(300) were obtained the pKa1 = 4.47 pKa2 = 9.34

21. Vanillin result data pH Titration Curves of Vanillin, at lmax(348), pKa = 7.25.

22. Study of aggregation by Uv/Vis Spectroscopy • p-Coumaric acid • Other components are under investigations.

23. Absorbance spectra of a series of concentrations of p-Coumaric acid in ethanol +

24. Conclusions I am tested four aromatic compounds, p-Coumaric acid, Ferulic acid, Syringic acid and Vanillin. All they basically have phenyl group and the first three also have the carboxylic acid chromophore.The first three have tow pKavalues because they have carbonyl group (>C=O) chromophore. The pKa value of a chemical compound determines its solubility and stability. Inethanol the p-Coumaric acid at high concentration makes dimerisation.

25. The four aromatic compounds

26. That’s all! Thank you very much for your attention