Synthesis of nanostructures from Phoenix dactylifera agro-wastes

Patent metadata

Field	Value
Publication number	US-9896342-B1
Application number	US-201715717604-A
Country	US
Kind code	B1
Filing date	Sep 27, 2017
Priority date	Sep 27, 2017
Publication date	Feb 20, 2018
Grant date	Feb 20, 2018

Abstract

A method of synthesizing nanostructures from agro-waste can include providing powdered Phoenix dactylifera agro-waste; mixing the powdered Phoenix dactylifera agro-waste with a liquid to provide a Phoenix dactylifera agro-waste solution; heating the Phoenix dactylifera agro-waste solution in a hydrothermal autoclave to provide a heated solution; and centrifuging the heated solution to provide a liquid fraction and a solid fraction. The liquid fraction can include a first plurality of nanostructures. The first plurality of nanostructures can include C-dots. The solid fraction can be further processed to provide a second plurality of nanostructures and a third plurality of nanostructures. The second plurality of nanostructures can include lignin nanoparticles. The third plurality of nanostructures can include cellulose nanocrystals. The nanostructures can be used in various applications, such as three dimensional cell culture, UV-protecting textiles, and bio-imaging.

First claim

We claim:

1. A method of synthesizing nanostructures from agro-waste comprising:
providing powdered Phoenix dactylifera agro-waste;
mixing the powdered Phoenix dactylifera agro-waste with a liquid to provide a Phoenix dactylifera agro-waste solution;
heating the Phoenix dactylifera agro-waste solution in a hydrothermal autoclave to provide a heated solution; and
centrifuging the heated solution to provide a liquid fraction and a solid fraction, the liquid fraction including a first plurality of nanostructures, the first plurality of nanostructures including C-dots.

2. The method of claim 1 , wherein the liquid comprises water and the Phoenix dactylifera agro-waste solution is kept in hydrothermal autoclave at about 180 C for about two hours.

3. The method of claim 1 , further comprising:
mixing the solid fraction with a base to provide a basic solution;
heating the basic solution in an autoclave to provide a heated basic solution;
filtering the heated basic solution to obtain a filtered solid fraction and a filtered liquid fraction;
adjusting a pH of the filtered liquid fraction to provide a precipitate;
washing the precipitate;
dissolving the precipitate in a solvent; and
dialyzing the solvent to provide a second plurality of nanostructures, the second plurality of nanostructures including lignin nanoparticles.

4. The method of claim 3 , wherein the base is 5% sodium hydroxide.

5. The method of claim 3 , wherein pH is adjusted to 2 using diluted hydrochloric acid.

6. The method of claim 3 , wherein the precipitate is washed with distilled water.

7. The method of claim 3 , wherein the solvent is THF solution.

8. The method of claim 3 , further comprising:
bleaching the filtered solid fraction using a bleaching solution to obtain a residue;
washing the residue to provide a pH neutral residue;
mixing the pH neutral residue with an acid under stirring to provide a mixture;
cooling the mixture to provide an incubated product;
centrifuging the incubated product to provide a centrifuged residue;
sonicating the centrifuged residue to provide a product including a third plurality of nanostructures, the third plurality of nanostructures including cellulose nanofibrils.

9. The method of claim 8 , wherein the bleaching occurs at 95° C. for 90 minutes and wherein the bleaching solution is a 1:1 solution of 1.7% sodium hypochlorite and acetate buffer.

10. The method of claim 8 , wherein the mixing includes mixing with 45% sulfuric acid at 45° C. for 25 minutes.

11. The method of claim 8 , wherein the cooling occurs at a temperature of about −80° C. for about 1 hour.

12. The method of claim 8 , wherein the sonicating occurs for 10 minutes.

Assignees

• Univ King Saud

Inventors

• Alshatwi Ali Abdullah
• Athinarayanan Jegan
• Subbarayan Periasamy Vaiyapuri

Classifications

• D21C1/06 Primary

  with alkaline reacting compounds · CPC title

• C01P2004/64

  Nanometer sized, i.e. from 1-100 nanometer · CPC title

• D21C3/04

  with acids, acid salts or acid anhydrides {(D21C3/003 and D21C3/222 take precedence)} · CPC title

• B82Y30/00

  Nanotechnology for materials or surface science, e.g. nanocomposites · CPC title

• C01P2004/04

  obtained by TEM, STEM, STM or AFM · CPC title