The development of an environmentally benign process for extraction of valued chemicals by catalytic hydrolysis of cellulose is considered as one of the key technologies for making complete usage of cellulosic biomacromolecules in near future. Present research deals with the application of Lewis acid of iron(III) chloride (FeCl3) based catalytic hydrolysis system which is capable of enhancing the crystallinity index of alpha-cellulose relatively at lower reaction temperature using moderate to dilute mineral acid. Process parameters were optimized by 2-Level Factorial Central Composite Design (CCD) approach to obtain microcrystalline cellulose (MCC) from alpha-cellulose. Process variables such as temperature (x(1)), hydrolyzing time (x(2)) and concentration of FeCl3 catalyst solution in HCl (2.5 M) acid were studied. Responses selected were yield (y(1)) and percentage crystallinity (y(2)) of the finally procured MCC sample. Regression analysis was accomplished to develop significant models. Analysis of Variance (ANOVA) showed that temperature was the most persuasive aspect for hydrolyzing the amorphous segments of cellulose. Under optimum condition, percentage yield and percentage crystallinity obtained were 83.21 +/- 0.23 and 86.98 +/- 0.32 respectively. The results elucidated that, catalytic effect of FeCl3 salt in presence of mineral acid can considerably increase the crystallinity of alpha-cellulose up to a certain extent by selective hydrolysis of amorphous domain while keeping the crystalline region almost unaltered.

The objective of this study was to explore the influence of pyrolysis temperature on the physicochemical properties of biochar synthesized from durian wood (Durio zibethinus) sawdust. Surface morphological features, including the porosity and BET surface area of biochars, provide appropriate dimensions for growing clusters of microorganisms with excellent water retention capacity in soil. Oxygen-containing surface functional groups play a vital role in improving soil fertility by increasing its cation and anion exchange capacities with reduced leaching of nutrients from the soil surface. Biochar was produced via slow pyrolysis of woody biomass (WS) using a fixed bed reactor under an oxygen-free atmosphere at different pyrolysis temperatures (350, 450, and 550 °C). The biochars obtained were characterized using ultimate and proximate analyses, Brunauer-Emmett-Teller (BET) surface area, field-emission scanning electron microscopy (FE-SEM), Fourier transform infrared spectroscopy (FTIR), and X-ray diffraction (XRD). The yield of biochar decreased from 66.46 to 24.56%, whereas the BET surface area increased sharply from 2.567 to 220.989 m2/g, when the pyrolysis temperature was increased from 350 to 550 °C. The results highlighted the effect of pyrolysis temperature on the structure of the biochar, which could be advantageous for agricultural industries.

This research emphasizes the isolation of nanocrystalline cellulose (NCC) from palm tree cellulose (PTC) and α-cellulose (AC), using acidic FeCl3-assisted catalytic pretreatment coupled with ultrasonication. The cavitation effect of ultrasonication affects the microstructure of the fibers, ultimately enhancing the crystallinity index of the prepared nanocrystalline cellulose (NCC) sample. In this research, Fourier transform infrared spectroscopy (FTIR) was used to identify the specific functional groups on both types of NCC sample. X-ray diffraction (XRD) analysis demonstrated that the isolated NCC from PTC and AC showed a higher crystallinity index of 73.51% and 89.03%, with diameters of 20 to 70 nm and 15 to 50 nm, respectively. The change in surface morphological features was observed by scanning electron microscopy (SEM), atomic force microscopy (AFM), and transmission electron microscopic (TEM) analysis. It was observed that PTC-based NCC had higher thermal stability than the starting cellulosic sample, whereas NCC isolated from AC showed an opposite trend of reduced thermal stability relative to the raw sample. The results indicated that catalytic acid hydrolysis with ultrasonication was able to yield up to 80.88% and 81.20% of NCC from PTC and AC, respectively, which is comparatively high enough for economic viability of the process.

Cellulosic fiber extracted from a non-woody, monocotyledonous species of palm tree trunk (PTT) was hydrolyzed with different concentrations of FeCl3 in the presence of hydrochloric acid. The dissolution properties of the amorphous region of palm tree cellulosic fiber (PTC) can be enhanced in the presence of Fe3+ cations in acidic medium. The independent variables, including temperature (x1), time (x2), and concentration of metal chloride (FeCl3) catalyst (x3), were optimized using central composite design (CCD). Responses were measured in terms of percentage crystallinity (y1) and yield (y2) of the prepared hydrocellulose. Analysis of variance (ANOVA) showed that temperature was the most influential factor for hydrolyzing the amorphous sections of cellulose. Under optimum conditions, the percentage crystallinity (y1) and yield (y2) were 68.66% and 83.98%, respectively. Scanning electron microscopy (SEM) analysis and X-ray diffraction techniques were used to obtain more information about the surface morphology and crystallinity of the prepared microcrystalline cellulose (MCC). Infrared spectroscopy and thermal analysis were performed to observe the effect of hydrolysis on the finished products. It was concluded that the addition of FeCl3 salt in acid hydrolyzing medium can substantially increase the crystallinity of palm tree trunk cellulose with significant morphological changes to yield microcrystalline cellulose (MCC).

Hydrolyzing the amorphous region while keeping the crystalline region unaltered is the key technology for producing nanocellulose. This study investigated if the dissolution properties of the amorphous region of microcrystalline cellulose can be enhanced in the presence of Fe3+ salt in acidic medium. The process parameters, including temperature, time and the concentration of metal chloride catalyst (FeCl3), were optimized by using the response surface methodology (RSM). The experimental observation demonstrated that temperature and time play vital roles in hydrolyzing the amorphous sections of cellulose. This would yield hydrocellulose with higher crystallinity. The factors that were varied for the production of hydrocellulose were the temperature (x1), time (x2) and FeCl3 catalyst concentration (x3). Responses were measured in terms of percentage of crystallinity (y1) and the yield (y2) of the prepared hydrocellulose. Relevant mathematical models were developed. Analysis of variance (ANOVA) was carried out to obtain the most significant factors influencing the responses of the percentage of crystallinity and yield. Under optimum conditions, the percentage of crystallinity and yield were 83.46% and 86.98% respectively, at 90.95 °C, 6 h, with a catalyst concentration of 1 M. The physiochemical characteristics of the prepared hydrocellulose were determined in terms of XRD, SEM, TGA and FTIR analyses. The addition of FeCl3 salt in acid hydrolyzing medium is a novel technique for substantially increasing crystallinity with a significant morphological change.