To identify alpha and beta cellulose on the basis of extraction method, you need to follow some steps:

• First, you need to extract the crude cellulose from the plant material by removing the non-cellulosic components, such as lignin, hemicellulose, pectin, wax, etc. This can be done by using different chemical treatments, such as sodium chlorite, sodium hydroxide, sulfuric acid, hydrogen peroxide, etc. The choice of the chemical treatment depends on the type and composition of the plant material. For example, one study used sodium chlorite followed by sodium hydroxide, hydrochloric acid and hydrogen peroxide to extract cellulose from halophytes[1].
• Second, you need to fractionate the crude cellulose into alpha-, beta- and gamma-cellulose by using different concentrations of sodium hydroxide solution. Alpha-cellulose is the fraction that is insoluble in 17.5% sodium hydroxide solution, beta-cellulose is the fraction that is soluble in 17.5% sodium hydroxide solution but insoluble in 9.5% sodium hydroxide solution, and gamma-cellulose is the fraction that is soluble in 9.5% sodium hydroxide solution[2]. The fractions can be separated by filtration and washed with water and ethanol.
• Third, you need to measure the weight of each fraction and calculate their percentage in the crude cellulose. You can also perform some characterization techniques, such as X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, etc., to analyze the structure and properties of each fraction[1-3].

Some references that provide more details about the extraction and identification of alpha and beta cellulose are:

• Extraction and characterization of cellulose from halophytes: next generation source of cellulose fibre by Aneesha Singh et al., published in SN Applied Sciences in 2019[1].
• An extractive removal step optimized for a high-throughput α-cellulose extraction method for δ13C and δ18O stable isotope ratio analysis in conifer tree rings by Wen Lin et al., published in Tree Physiology in 2017[3].
• Method for determining alpha-, beta- and gamma- cellulose contents in the dissolving pulp by Zhang Xiaohui et al., published in CN105572260A patent document in 2016[4].
• Alpha-cellulose in paper, Test Method T 429 cm-10 by TAPPI Press in 2010[2].
• Simplified volumetric determination of alpha, beta, and gamma cellulose fractions by J. A. Marston et al., published in Journal of Research of the National Bureau of Standards in 1937[5].

Article Extraction and characterization of cellulose from halophytes...

https://www.tappi.org/product_pull/09/dec/__03/alpha-cellulose-in-paper-test-method-t-429-cm-10/

https://academic.oup.com/treephys/article/37/1/142/2548376

https://nvlpubs.nist.gov/nistpubs/jres/18/jresv18n3p333_A1b.pdf

Article An extractive removal step optimized for a high-throughput α...

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