Georgia Institue of Technology, Atlantaīansal P, Hall M, Realff MJ et al (2010) Multivariate statistical analysis of X-ray data from cellulose: a new method to determine degree of crystallinity and predict hydrolysis rates. īansal P (2011) Computational and experimental investigation of the enzymatic hydrolysis of cellulose. (01)00167-2Īzubuike CP, Rodríguez H, Okhamafe AO, Rogers RD (2012) Physicochemical properties of maize cob cellulose powders reconstituted from ionic liquid solution. Cellulose 23:1–14Īstley OM, Chanliaud E, Donald AM, Gidley MJ (2001) Structure of acetobacter cellulose composites in the hydrated state. Graphic abstractĪhvenainen P, Kontro I, Svedström K (2016) Comparison of sample crystallinity determination methods by X-ray diffraction for challenging cellulose I materials. Results suggest that prior peak deconvolution methods overestimate cellulose crystallinity. Analysis of several cellulose samples was then performed and compared to the conventional peak deconvolution methods with common peak fitting functions and background subtraction approach. The impact of background subtraction method has also been assessed. A new peak deconvolution method then is proposed to analyze cellulose XRD data with the amorphous Fourier model function in conjunction with standard Voigt functions representing the crystalline peaks.
#CELLULSOE X RAY DIFFRACTION PATTERN SERIES#
The amorphous XRD profile is modeled using a Fourier series equation where the coefficients are determined using the nonlinear least squares method. This agrees well with cellulose I d-spacing measurements and oligosaccharide XRD analysis. It is hypothesized that short range order within a glucose unit and between adjacent units survives ball milling and generates the characteristic amorphous XRD profiles. It first examines the effects of ball milling on three types of cellulose and results show that ball milling transforms all samples into a highly amorphous phase exhibiting nearly identical powder X-ray diffraction (XRD) profiles. The micrographic features showed the acid hydrolysis had successfully took place and separated the EFB microfibrils bundles.This paper addresses two fundamental issues in the peak deconvolution method of cellulose XRD data analysis: there is no standard model for amorphous cellulose and common peak functions such as Gauss, Lorentz and Voigt functions do not fit the amorphous profile well. Fourier Transform infrared (FTIR) spectra showed the presence of similar peaks in AH-EFB and commercial microcrystalline cellulose (C-MCC) at 1427, 1315, 8 cm -1. This is due to the removal of amorphous part contributed by lignin, hemicellulose and cellulose. Based on the calculation, increment of about 1.3 times and 1.5 times were achieved by using WAXS and XRD deconvolution methods respectively. XRD peak high and XRD deconvolution methods were used to calculate and compare the percentage of crystallinity of untreated EFB (UT-EFB) and acid hydrolyzed samples (AH-EFB). These changes were described in term of polymorphs type present, reflection and allomorphs of the samples. The XRD patterns significantly showed changes in the 2θ peaks before and after the treatment. The reaction was carried out by soaking EFB in 1% (v/v) aqueous sulfuric acid (H 2SO 4) at different temperatures of 120, 130 and 140☌ for 1 h. In this paper, we focused on the effect of acid hydrolysis onto EFB on the crystallinity of the extracted cellulose. Crystallinity of oil palm fiber from empty fruit bunch (EFB) with and without tretaments was studied by analyzing the X-ray diffraction (XRD) pattern.
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