Effects on the yield of isolated cellulose in a scale-up model

Lê, Thị Thanh Hương1 ; Tran, Hoang Huu2 ; Tran Nguyen Minh, An2

Research facility: Equiment for cooking Kraft pulp at laboratory*

Published Jan 10, 2025 on Dryad. https://doi.org/10.5061/dryad.7m0cfxq44

Data files

Jan 10, 2025 version files 55.60 KB

Data_tables.zip
49.30 KB
README.md
6.31 KB

Abstract

This study focuses on fabricating a cellulose aerogel for efficient oil spill cleanup, using common reed (Phragmites australis) as the cellulose source. The process involves isolating cellulose from reed via traditional Kraft pulping, considering the effects of key factors on isolated cellulose content. After a two-stage HP bleaching sequence, the highest cellulose content achieved 27.2%, with 80% ISO brightness and 1% ash content under mild Kraft pulping conditions of 30% sulfidity, 20% active alkali, sustained cooking at 165 °C for 3 hours, and a liquor-to-reed ratio of 8:1. Subsequently, reed-based cellulose aerogel was fabricated via freeze-dried method using eco-friendly NaOH/PEG aqeous solvent system, which was then modified with (methyltrimethoxysilane) MTMS. The resulting aerogel exhibited remarkable characteristics, including a low density of 0.04 g/cm³, high porosity of 96%, superhydrophobicity with a water contact angle of 141°, and a superior crude oil adsorption capacity of 35 g/g. Comprehensive characterizations of fabricated materials, including SEM, FTIR, TGA/DSC, and WAC measurements, were evaluated. This interdisciplinary study explores the commercial promise of reed-based cellulose aerogel as a sustainable solution for oil spill cleanup efforts.

README: Effects on the yield of isolated cellulose in a scale-up model

Description of the data and file structure:

The Data_Tables.zip file contains four Excel files documenting the entire Kraft pulping of reed feedstock. The results are presented in the following files:

Effect of sulfidity on isolated cellulose.xlsx: Sulfidity is a key variable in Kraft pulping that influences the efficiency of the pulping process and the quality of the isolated cellulose;
Effect of active alkali on isolated cellulose.xlsx: Active alkali (AA), consisting of NaOH and Na₂S, serves as the active agent in Kraft pulping;
Effect of L:Q ratio on isolated cellulose.xlsx: The liquid-to-solid ratio needs to be carefully controlled as it affects the diffusion of chemicals into materials containing cellulose, lignin, hemicellulose, and other components;
Effect of cooking time on isolated cellulose.xlsx: Cooking time affects cellulose degradation, influencing the yield and quality of the isolated cellulose.

Descriptions

Effect of sulfidity on isolated cellulose

Entry: The number of the experiment, ranging from 1 to 4.
Reed chips: The constant feedstock of 0.5 kg used in Kraft pulping for cellulose isolation (kg).
AA% (active alkali percentage): The constant active alkali percentage of 0.2%, calculated based on the Na₂O equivalent in NaOH and Na₂S (%).
- NaOH: The amount of NaOH, measured in kilograms (kg).
- Na₂S: The amount of Na₂S, measured in kilograms (kg).
Sulfidity (%): The percentage of sulfidity, which was varied from 10% to 35%.
L:W ratio: The ratio of pulping liquor (kg) to the oven-dry weight of reed chips (kg). In this case, the L:W ratio is constant at 10:1.
Temperature: The cooking temperature (°C), which is set constant at 165°C.
Cooking time: The duration of cooking the reed chips (in hours), set constant at 2.5 hours in this case.
% Isolated cellulose: The percentage yield of purified cellulose isolated after cooking reed chips.

Effect of active alkali on isolated cellulose

Entry: The number of the experiment, ranging from 1 to 4.
Reed chips: The constant feedstock of 0.5 kg used in Kraft pulping for cellulose isolation (kg).
AA% (active alkali percentage): The constant active alkali percentage of 0.2%, calculated based on the Na₂O equivalent in NaOH and Na₂S (%), which was varied from 10% to 25%.
- NaOH: The amount of NaOH, measured in kilograms (kg).
- Na₂S: The amount of Na₂S, measured in kilograms (kg).
Sulfidity (%): The sulfidity percentage was set constant at 30%, based on the best value observed in previous experiments on the effect of sulfidity on isolated cellulose.
L:W ratio: The ratio of pulping liquor (kg) to the oven-dry weight of reed chips (kg). In this case, the L:W ratio is constant at 10:1.
Temperature: The cooking temperature (°C), which is set constant at 165°C.
Cooking time: The duration of cooking the reed chips (in hours), set constant at 2.5 hours in this case.
% Isolated cellulose: The percentage yield of purified cellulose isolated after cooking reed chips.

Effect of L.Q ratio on isolated cellulose

Entry: The number of the experiment, ranging from 1 to 4.
Reed chips: The constant feedstock of 0.5 kg used in Kraft pulping for cellulose isolation (kg).
AA%: The active alkali percentage, calculated based on the Na₂O equivalent in NaOH and Na₂S (%), was set constant at 15%, based on the best value observed in previous experiments on the effect of active alkali on isolated cellulose.
- NaOH: The amount of NaOH, measured in kilograms (kg).
- Na₂S: The amount of Na₂S, measured in kilograms (kg).
Sulfidity (%): The sulfidity percentage was set constant at 30%, based on the best value observed in previous experiments on the effect of sulfidity on isolated cellulose.
L:W ratio: The ratio of pulping liquor (kg) to the oven-dry weight of reed chips (kg). In this case, the ratios used were L:W = 6:1, L:W = 8:1, L:W = 10:1, and L:W = 12:1.
Temperature: The cooking temperature (°C), which is set constant at 165°C.
Cooking time: The duration of cooking the reed chips (in hours), set constant at 2.5 hours in this case.
% Isolated cellulose: The percentage yield of purified cellulose isolated after cooking reed chips.

Effect of cooking time on isolated cellulose

Entry: The number of the experiment, ranging from 1 to 4.
Reed chips: The constant feedstock of 0.5 kg used in Kraft pulping for cellulose isolation (kg).
AA%: The active alkali percentage, calculated based on the Na₂O equivalent in NaOH and Na₂S (%), was set constant at 15%, based on the best value observed in previous experiments on the effect of active alkali on isolated cellulose.
- NaOH: The amount of NaOH, measured in kilograms (kg).
- Na₂S: The amount of Na₂S, measured in kilograms (kg).
Sulfidity (%): The sulfidity percentage was set constant at 30%, based on the best value observed in previous experiments on the effect of sulfidity on isolated cellulose.
L:W ratio: The ratio of pulping liquor (kg) to the oven-dry weight of reed chips (kg). In this case, L:Q was set constat at 8:1, based on the best value observed in previous experiments on the effect of L:W ratio on isolated cellulose.
Temperature: The cooking temperature (°C), which is set constant at 165°C.
Cooking time: The duration of cooking the reed chips (in hours), was varied from 2 hours to 3.5 hours.
% Isolated cellulose: The percentage yield of purified cellulose isolated after cooking reed chips.

Version changes

24-Dec-2024:

Deleted one unnecessary first column from the two Sulfidity columns (%) in the "Effect of Sulfidity on Isolated Cellulose" sheet.
Edited all AA (%) columns in the "Effect of L:W Ratio on Isolated Cellulose" sheet and the "Effect of Cooking Time on Isolated Cellulose" sheet to a fixed value of 15%, as this represents the best AA percentage determined from previous experiments on the "Effect of Active Alkali on Isolated Cellulose."
Revised all instances of "L/Q" to "L:Q" for consistency with the manuscript.
Corrected spelling errors and formatting in all four sheets of the Data-Tables.