Novel dual modified alkali lignin based adsorbent for the removal of Pb2+ in water

2021 ◽  
Vol 173 ◽  
pp. 114100
Author(s):  
Zhaohui Zhang ◽  
Chaojun Wu ◽  
Qijun Ding ◽  
Dongmei Yu ◽  
Ronggang Li
Keyword(s):  
Alkali Lignin

Low-temperature alkali lignin depolymerization to functional chemicals

2021 ◽  
Author(s):  
Komal Saini ◽  
Avnish Kumar ◽  
Bijoy Biswas ◽  
Thallada Bhaskar
Keyword(s):  
Low Temperature ◽  
Alkali Lignin ◽  
Lignin Depolymerization

Effective depolymerization of alkali lignin into phenolic monomers over ZrP catalysts promoted by Ni and W

2021 ◽  
Author(s):  
Dandan Wang ◽  
Xinyu Lu ◽  
Haoquan Guo ◽  
Pengcheng Xiu ◽  
Jiajia Chen ◽  
...  
Keyword(s):  
Alkali Lignin

Isolation and characterization of a fungus Aspergillus sp. strain F-3 capable of degrading alkali lignin

2011 ◽  
Vol 22 (5) ◽  
pp. 1017-1027 ◽  
Author(s):  
Y. S. Yang ◽  
J. T. Zhou ◽  
H. Lu ◽  
Y. L. Yuan ◽  
L. H. Zhao
Keyword(s):  
Alkali Lignin ◽  
Isolation And Characterization ◽  
Aspergillus Sp

scholarly journals Characterisation of Sequential Solvent Fractionation and Base-catalysed Depolymerisation of Treated Alkali Lignin

BioResources ◽  
2015 ◽  
Vol 10 (3) ◽  
pp. 4137-4151 ◽  
Author(s):  
Aikfei Ang ◽  
Zaidon Ashaari ◽  
Edi Suhaimi Bakar ◽  
Nor Azowa Ibrahim
Keyword(s):  
Molecular Weight ◽  
Chemical Structure ◽  
Average Molecular Weight ◽  
Gel Permeation Chromatography ◽  
Solubility Parameters ◽  
Low Molecular Weight ◽  
Sequential Fractionation ◽  
Weight Average Molecular Weight ◽  
Solvent Fractionation ◽  
Alkali Lignin

An alkali lignin (OL) with a weight-average molecular weight (Mw) of 11646 g/mol was used to prepare low-molecular weight lignin for resin synthesis. The low-molecular weight lignin feedstock was obtained via base-catalysed depolymerisation (BCD) treatments at different combined severity factors. Sequential fractionation of the OL and BCD-treated lignins using organic solvents with different Hildebrand solubility parameters were used to alter the homogeneity of the OL. The yield and properties of OL itself and OL and BCD-treated OL dissolved in propan-1-ol (F1), ethanol (F2), and methanol (F3) were determined. Regardless of the treatment applied, a small amount of OL was dissolved in F1 and F2. The BCD treatment did not increase the yield of F1 but did increase the yields of F2 and F3. Gel permeation chromatography (GPC) showed that the repolymerization reaction occurred in F3 for all BCD-treated OL, so these lignins were not suitable for use as feedstocks for resin production. The GPC, 13Carbon-nuclear magnetic resonance, and Fourier transform infrared spectroscopy analyses confirmed that the F3 in OL exhibited the optimum yield, molecular weight distribution, and chemical structure suitable for use as feedstocks for resin synthesis.

Enhanced Thermal Stability of Esterified Lignin in Different Solvent Mediums

2018 ◽  
Vol 9 (1) ◽  
pp. 39-49 ◽  
Author(s):  
Sharifah Nurul Ain Syed Hashim ◽  
Sarani Zakaria ◽  
Chin Hua Chia ◽  
Sharifah Nabihah Syed Jaafar
Keyword(s):  
Thermal Stability ◽  
Alkaline Solution ◽  
Room Temperature ◽  
Hydroxyl Groups ◽  
Aqueous Alkaline Solution ◽  
Alkali Lignin ◽  
Weight Percentage ◽  
H Nmr ◽  
Ft Ir ◽  
Thermal Stability Of

In this study, soda alkali lignin from oil palm empty fruit bunch (EFB-AL) and kenaf core (KC-AL) are esterified with maleic anhydride under two different conditions, namely i) pyridine at temperature of 120°C for 3h and ii) aqueous alkaline solution at room temperature for 4h. As a result, the weight percentage gain (WPG) of the esterified EFB-AL (EFB-EL) and esterified KC-AL (KC-EL) in pyridine demonstrated a higher compared to aqueous alkaline solution. The FT-IR results of EFB-EL and KC-EL in both solvents exhibited some changes at the carbonyl and hydroxyl groups. Furthermore, the esterification process induced the carboxylic peak to appear in both alkali lignin samples. The outcome is confirmed by conducting H-NMR analysis, which demonstrated ester and carboxylic acid peaks within the spectral analysis. Finally, the TGA results showed both EFB-EL and KC-EL that are exposed to aqueous alkaline actually possessed better thermal stability and higher activation energy (Ea) compared to the esterified samples in pyridine.

Preparation of Water-Soluble Carboxymethylated Lignin from Wheat Straw Alkali Lignin

2012 ◽  
Vol 550-553 ◽  
pp. 1293-1298 ◽  
Author(s):  
Lin Huo Gan ◽  
Ming Song Zhou ◽  
Xue Qing Qiu
Keyword(s):  
Wheat Straw ◽  
Acid Concentration ◽  
1H Nmr Spectroscopy ◽  
Water Soluble ◽  
Monochloroacetic Acid ◽  
Hydroxyl Group ◽  
Carboxyl Group ◽  
Optimum Conditions ◽  
Alkali Lignin ◽  
Carboxyl Group Content

Water-soluble carboxymethylated lignin (CML) was synthesized using wheat straw alkali lignin (WAL) in aqueous medium. The process of carboxymethylation was optimized with respect to the NaOH concentration, monochloroacetic acid concentration, reaction temperature and time. The optimized product has a yield of 80.47% and a carboxyl group content of 2.8231 mmol•g-1, respectively. The optimum conditions for carboxymethylation are NaOH concentration of 20.0% (wt%), monochloroacetic acid concentration of 37.5% (wt%), temperature of 70 °C and time of 90 min. The optimized CML was characterized by FTIR spectroscopy, 1H NMR spectroscopy and interfacial tension apparatus. The result shows that the substitution reaction of carboxymethylation occurs simultaneously in the phenolic hydroxyl group and aliphatic hydroxyl group in WAL. CML has the surface activity in water for industrial application as dispersant.

scholarly journals Studies on the Utilization of Alkali Lignin (Part 2)

1970 ◽  
Vol 24 (8) ◽  
pp. 424-428 ◽  
Author(s):  
Shoji Kagawa
Keyword(s):  
Alkali Lignin
Sign in / Sign up

Export Citation Format

Share Document