Nanocellulose from rice husk following alkaline treatment to remove silica

The present work deals with the use of multiple-step procedures to obtain valuable sub-products, including nanocellulose, from rice husk. Each sub-product was characterized after every step by analyzing the chemical composition (mainly based on thermogravimetric analysis, Fourier transformed infrared spectra, and X-ray diffraction) and morphology (using visual observations and scanning electron microscopy). The results clearly showed that the selected procedure gave the possibility to separate silica in the first step and then to purify the resultant material, leading to nanocellulose production. All acquired sub-products can be used as additives and fillers in a very wide range of applications. The obtained results will be useful both from technological and academic points of view, mainly for people working in the field of biocomposites. The final material could give added value to a raw biomass material source such as rice husk.

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Multidimensional Ln-Aminophthalate Photoluminescent Coordination Polymers

Materials ◽

10.3390/ma14071786 ◽

2021 ◽

Vol 14 (7) ◽

pp. 1786

Author(s):

Carla Queirós ◽

Chen Sun ◽

Ana M. G. Silva ◽

Baltazar de Castro ◽

Juan Cabanillas-Gonzalez ◽

...

Keyword(s):

Water Content ◽

Coordination Polymers ◽

Metal Ion ◽

Low Cost ◽

Microwave Assisted Synthesis ◽

X Ray Diffraction ◽

X Ray ◽

Wide Range ◽

Ft Ir ◽

Ft Ir Spectroscopy

The development of straightforward reproducible methods for the preparation of new photoluminescent coordination polymers (CPs) is an important goal in luminescence and chemical sensing fields. Isophthalic acid derivatives have been reported for a wide range of applications, and in addition to their relatively low cost, have encouraged its use in the preparation of novel lanthanide-based coordination polymers (LnCPs). Considering that the photoluminescent properties of these CPs are highly dependent on the existence of water molecules in the crystal structure, our research efforts are now focused on the preparation of CP with the lowest water content possible, while considering a green chemistry approach. One- and two-dimensional (1D and 2D) LnCPs were prepared from 5-aminoisophthalic acid and Sm3+/Tb3+ using hydrothermal and/or microwave-assisted synthesis. The unprecedented LnCPs were characterized by single-crystal X-ray diffraction (SCRXD), powder X-ray diffraction (PXRD), Fourier transform infrared (FT-IR) spectroscopy and scanning electron microscopy (SEM), and their photoluminescence (PL) properties were studied in the solid state, at room temperature, using the CPs as powders and encapsulated in poly(methyl methacrylate (PMMA) films, envisaging the potential preparation of devices for sensing. The materials revealed interesting PL properties that depend on the dimensionality, metal ion, co-ligand used and water content.

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Preliminary Preparation and Characterization Studies of Cellulose from Merbau (Intsia bijuga)

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.620.314 ◽

2012 ◽

Vol 620 ◽

pp. 314-319

Author(s):

Nur Amira Mamat Razali ◽

Fauziah Abdul Aziz ◽

Saadah Abdul Rahman

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Alkaline Treatment ◽

Raw Material ◽

X Ray Diffraction ◽

X Ray ◽

Preliminary Preparation ◽

Characterization Studies ◽

Scanning Electron

Hardwood is wood from angiosperm trees. The characteristic of hardwood include flowers, endosperm within seeds and the production of fruits that contain the seeds. This paper aims to discuss the preparation and characterization of cellulose obtained from hardwood. The hardwood Merbau (Intsia bijuga) was chosen as raw material in this study. Alkaline treatment and delignification methods were used for the preparation of cellulose. Acid hydrolysis was employed to produce cellulose nanocrystal (CNC). The treated and untreated samples were characterized using x-ray diffraction (XRD) and field emission scanning electron microscopy (FE-SEM). The final product, from both trated and untreated samples were then compared.

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Full-field X-ray diffraction microscopy using polymeric compound refractive lenses

Journal of Applied Crystallography ◽

10.1107/s1600576714021256 ◽

2014 ◽

Vol 47 (6) ◽

pp. 1882-1888 ◽

Cited By ~ 11

Author(s):

J. Hilhorst ◽

F. Marschall ◽

T. N. Tran Thi ◽

A. Last ◽

T. U. Schülli

Keyword(s):

Imaging Techniques ◽

Light And Electron Microscopy ◽

Added Value ◽

Acquisition Time ◽

Imaging Method ◽

X Ray Diffraction ◽

Polymeric Compound ◽

Full Field ◽

X Ray ◽

Diffraction Imaging

Diffraction imaging is the science of imaging samples under diffraction conditions. Diffraction imaging techniques are well established in visible light and electron microscopy, and have also been widely employed in X-ray science in the form of X-ray topography. Over the past two decades, interest in X-ray diffraction imaging has taken flight and resulted in a wide variety of methods. This article discusses a new full-field imaging method, which uses polymer compound refractive lenses as a microscope objective to capture a diffracted X-ray beam coming from a large illuminated area on a sample. This produces an image of the diffracting parts of the sample on a camera. It is shown that this technique has added value in the field, owing to its high imaging speed, while being competitive in resolution and level of detail of obtained information. Using a model sample, it is shown that lattice tilts and strain in single crystals can be resolved simultaneously down to 10−3° and Δa/a= 10−5, respectively, with submicrometre resolution over an area of 100 × 100 µm and a total image acquisition time of less than 60 s.

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2D X-ray diffraction and molecular modelling of the crystalline structure of polyesters under uniaxial stress

Polymers and Polymer Composites ◽

10.1177/0967391121998225 ◽

2021 ◽

pp. 096739112199822

Author(s):

Ahmed I Abou-Kandil ◽

Gerhard Goldbeck

Keyword(s):

Crystalline Structure ◽

Molecular Modelling ◽

Three Dimensional ◽

Uniaxial Stress ◽

X Ray Diffraction ◽

X Ray ◽

Wide Range ◽

Modelling Techniques ◽

Diffraction Patterns

Studying the crystalline structure of uniaxially and biaxially drawn polyesters is of great importance due to their wide range of applications. In this study, we shed some light on the behaviour of PET and PEN under uniaxial stress using experimental and molecular modelling techniques. Comparing experiment with modelling provides insights into polymer crystallisation with extended chains. Experimental x-ray diffraction patterns are reproduced by means of models of chains sliding along the c-axis leading to some loss of three-dimensional order, i.e. moving away from the condition of perfect register of the fully extended chains in triclinic crystals of both PET and PEN. This will help us understand the mechanism of polymer crystallisation under uniaxial stress and the appearance of mesophases in some cases as discussed herein.

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Development of Ternary Concrete Utilizing Agricultural Waste Material

10.21203/rs.3.rs-1107515/v1 ◽

2022 ◽

Author(s):

Sunita Kumari ◽

Dhirendra Singhal ◽

Rinku Walia ◽

Ajay Rathee

Keyword(s):

Rice Husk ◽

Rice Husk Ash ◽

Agricultural Waste ◽

Xrd Analysis ◽

Sem Analysis ◽

X Ray Diffraction ◽

X Ray ◽

Concrete Mix ◽

Maize Cob

Abstract The present project proposes to utilize rice husk and maize cob husk ash in the cement to mitigate the adverse impact of cement on environment and to enhance the disposal of waste in a sustainable manner. Ternary concrete / MR concrete was prepared by using rise husk and maize cob ash with cement. For the present project, five concrete mixes MR-0 (Control mix), MR-1 (Rice husk ash 10% and MR-2.5%), MR-2 (Rice husk ash 10% and MR-5%), MR-3 (Rice husk ash 10% and MR-2.5%), MR-4 (Rice husk ash 10% and MR-2.5%) were prepared. M35 concrete mix was designed as per IS 10262:2009 for low slump values 0-25mm. The purpose is to find the optimum replacement level of cement in M35 grade ternary concrete for I – Shaped paver blocks.In order to study the effects of these additions, micro-structural and structural properties test of concretes have been conducted. The crystalline properties of control mix and modified concrete are analyzed by Fourier Transform Infrared Spectroscope (FTIR), Scanning Electron Microscopy (SEM), and X-Ray Diffraction (XRD). The results indicated that 10% Rice husk ash and 5% maize cob ash replaced with cement produce a desirable quality of ternary concrete mix having good compressive strength. The results of SEM analysis indicated that the morphology of both concrete were different, showing porous structure at 7 days age and become unsymmetrical with the addition of ashes. After 28 day age, the control mix contained more quantity of ettringite and became denser than ternary concrete. XRD analysis revealed the presence of portlandite in large quantity in controlled mix concrete while MR concrete had the partially hydrated particle of alite.

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Pengaruh Suhu Kalsinasi terhadap Karakteristik Komposit Forsterit-Karbon Tersintesis dalam Medium Gas Argon

ALCHEMY Jurnal Penelitian Kimia ◽

10.20961/alchemy.16.2.34845.12-19 ◽

2020 ◽

Vol 16 (2) ◽

pp. 12

Author(s):

Solihudin Solihudin ◽

Haryono Haryono ◽

Atiek Rostika Noviyanti ◽

Muhammad Rizky Ridwansyah

Keyword(s):

Fourier Transform ◽

Electron Microscope ◽

Scanning Electron Microscope ◽

Rice Husk ◽

Energy Dispersive Spectroscopy ◽

Carbon Composite ◽

X Ray Diffraction ◽

Argon Gas ◽

X Ray ◽

Scanning Electron

Komposit forsterit-karbon merupakan salah satu material modifikasi dari forsterit yang berpotensi memiliki sifat isolator panas baik. Karbon dalam komposit dapat mengisi cacat titik pada kristal forsterit. Arang sekam padi (residu gasifikasi) mengandung SiO2 amorf dan karbon yang tinggi. Penelitian ini bertujuan menentukan pengaruh suhu kalsinasi dalam medium gas inert (dengan pengaliran gas argon) terhadap karakteristik komposit forsterit-karbon dari arang sekam padi dan magnesium karbonat. Metode penelitian meliputi preparasi arang sekam padi hasil gasifikasi, dan sintesis forsterit-karbon. Proses sintesis komposit forsterit karbon dilakukan dengan cara mencampurkan arang sekam padi dengan kalium karbonat pada rasio mol magmesium terhadap silikon sebesar 2 : 1 kemudian dikalsinasi dengan suhu divariasikan (700, 800, 900, dan 1000 oC). Selanjutnya sampel hasil sintesis dikarakterisasi dengan Fourier-transform infrared (FTIR), X-ray diffraction (XRD), dan scanning electron microscope-energy dispersive spectroscopy (SEM-EDS). Hasil karakterisasi dengan FTIR dan XRD diperoleh kesimpulan bahwa forsterit mulai terbentuk pada suhu kalisiasi 800 oC dan sempurna pada suhu 1000 oC, karenanya komposit yang terbentuk pada 1000 oC dimungkinkan sebagai forsterit-karbon, di mana unsur-unsur yang terkandung ditunjukkan oleh SEM-EDS. The Effect of Calcination Temperature on the Characteristics of Forsterite-Carbon Composites Synthesized in Argon Gas Medium. Forsterite-carbon composite is one of the material modifications of forsterite, which potentially has a good heat insulation property. Carbon in composites can fill point defects in forsterite crystals. Rice husk charcoal, as gasification residues, contains high amorphous SiO2 and carbon. This study aims to determine the effect of temperature on the calcination of a mixture of rice husk charcoal and magnesium carbonate under an inert gas (argon gas) on the characteristics of the forsterite-carbon composite produced. The experimental research performed includes the preparation of gasified rice husk charcoal and the synthesis of the carbon-forsterite composite. The synthesis process of the carbon-forsterite composites was carried out by mixing rice husk charcoal with potassium carbonate at a mole ratio of magnesium to silicon of 2 : 1. The mixture was then calcined with varying temperatures (700, 800, 900, and 1000 °C). Furthermore, the synthesized sample was characterized by Fourier-transform infrared (FTIR), X-ray diffraction (XRD), and scanning electron microscope-energy dispersive spectroscopy (SEM-EDS). The FTIR and XRD analysis show that the forsterites began to form at a calcination temperature of 800 °C and perfectly formed at a temperature of 1000 °C; therefore, the composite formed at 1000 °C is possible as forsterite-carbon, in which the contained elements were indicated by SEM-EDS.

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Theoretical study of the properties of X-ray diffraction moiré fringes. II. Illustration of angularly integrated moiré images

Acta Crystallographica Section A Foundations and Advances ◽

10.1107/s2053273319004601 ◽

2019 ◽

Vol 75 (4) ◽

pp. 610-623

Author(s):

Jun-ichi Yoshimura

Keyword(s):

Incident Wave ◽

Angular Width ◽

X Ray Diffraction ◽

Experimental Conditions ◽

Acta Cryst ◽

Low Contrast ◽

X Ray ◽

Moiré Fringes ◽

Wide Range ◽

Fringe Patterns

Using a theory of X-ray diffraction moiré fringes developed in a previous paper, labelled Part I [Yoshimura (2015). Acta Cryst. A71, 368–381], the X-ray moiré images of a silicon bicrystal having a weak curvature strain and an interspacing gap, assumed to be integrated for an incident-wave angular width, are simulation-computed over a wide range of crystal thicknesses and incident-wave angular width, likely under practical experimental conditions. Along with the simulated moiré images, the graphs of characteristic quantities on the moiré images are presented for a full understanding of them. The treated moiré images are all of rotation moiré. Mo Kα1 radiation and the 220 reflection were assumed in the simulation. The results of this simulation show that fringe patterns, which are significantly modified from simple straight fringes of rotation moiré, appear in some ranges of crystal thicknesses and incident-wave angular width, due to a combined effect of Pendellösung oscillation and an added phase difference from the interspacing gap, under the presence of a curvature strain. The moiré fringes which slope to the perpendicular direction to the diffraction vector in spite of the assumed condition of rotation moiré, and fringe patterns where low-contrast bands are produced with a sharp bend of fringes arising along the bands are examples of the modified fringe pattern. This simulation study provides a wide theoretical survey of the type of bicrystal moiré image produced under a particular condition.

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Charge Compensation in Europium-Doped Hafnia Nanoparticles: Solvothermal Synthesis and Colloidal Dispersion

Crystals ◽

10.3390/cryst11091042 ◽

2021 ◽

Vol 11 (9) ◽

pp. 1042

Author(s):

Xavier H. Guichard ◽

Francesco Bernasconi ◽

Alessandro Lauria

Keyword(s):

Low Temperature ◽

Hafnium Oxide ◽

Aqueous Media ◽

Charge Compensation ◽

Colloidal Dispersion ◽

X Ray Diffraction ◽

X Ray ◽

Wide Range ◽

Direct Formation ◽

Enhanced Luminescence

Effective charge compensation of europium in hafnium oxide nanoparticles was achieved at low temperature, allowing high doping incorporation (up to 6 at.%) and enhanced luminescence. The efficiency of the incorporation and charge compensation was confirmed by scanning electron microscope energy dispersive X-ray spectroscopy and powder X-ray diffraction measurements. Despite the known polymorphism of hafnium oxide, when doped to a concentration above 3 at.%, only the pure monoclinic phase was observed up to 6 at.% of europium. Furthermore, the low-temperature solvothermal route allowed the direct formation of stable dispersions of the synthesized material over a wide range of concentrations in aqueous media. The dispersions were studied by diffuse light scattering (DLS) to evaluate their quality and by photoluminescence to investigate the incorporation of the dopants into the lattice.

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In situ X-ray Diffraction Investigation of the Crystallisation of Perfluorinated Ce(IV)-based Metal-Organic Frameworks with UiO-66 and MIL-140 architectures

10.26434/chemrxiv.13252544 ◽

2020 ◽

Author(s):

Stephen Shearan ◽

Jannick Jacobsen ◽

Ferdinando Costantino ◽

Roberto D’Amato ◽

Dmitri Novikov ◽

...

Keyword(s):

Crystal Growth ◽

Metal Organic Frameworks ◽

Building Blocks ◽

Nucleation And Growth ◽

X Ray Diffraction ◽

X Ray ◽

Rate Determining Step ◽

Wide Range ◽

Metal Organic

We report on the results of a thorough in situ synchrotron powder X-ray diffraction study of the crystallisation in aqueous medium of two recently discovered perfluorinated Ce(IV)-based metal-organic frameworks (MOFs), analogues of the already well investigated Zr(IV)-based UiO-66 and MIL-140A, namely, F4_UiO-66(Ce) and F4_MIL-140A(Ce). The two MOFs were originally obtained in pure form in similar conditions, using ammonium cerium nitrate and tetrafluoroterephthalic acid as building blocks, and small variations of the reaction parameters were found to yield mixed phases. Here, we investigate the crystallisation of these compounds in situ in a wide range of conditions, varying parameters such as temperature, amount of the protonation modulator nitric acid (HNO3) and amount of the coordination modulator acetic acid (AcOH). When only HNO3 is present in the reaction environment, F4_MIL-140A(Ce) is obtained as a pure phase. Heating preferentially accelerates nucleation, which becomes rate determining below 57 °C, whereas the modulator influences nucleation and crystal growth to a similar extent. Upon addition of AcOH to the system, alongside HNO3, mixed-phased products, consisting of F4_MIL-140A(Ce) and F4_UiO-66(Ce), are obtained. In these conditions, F4_UiO-66(Ce) is always formed faster and no interconversion between the two phases occurs. In the case of F4_UiO-66(Ce), crystal growth is always the rate determining step. An increase in the amount of HNO3 slows down both nucleation and growth rates for F4_MIL-140A(Ce), whereas nucleation is mainly affected for F4_UiO-66(Ce). In addition, a higher amount HNO3 favours the formation of F4_MIL-140A(Ce). Similarly, increasing the amount of AcOH leads to slowing down of the nucleation and growth rate, but favours the formation of F4_UiO-66(Ce). The pure F4_UiO-66(Ce) phase could also be obtained when using larger amounts of AcOH in the presence of minimal HNO3. Based on these in situ results, a new optimised route to achieving a pure, high quality F4_MIL-140A(Ce) phase in mild conditions (60 °C, 1 h) is also identified.

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Comparison between Rice Husk Ash and Commercial Silica as Filler in Polymeric Composites

Materials Science Forum ◽

10.4028/www.scientific.net/msf.869.209 ◽

2016 ◽

Vol 869 ◽

pp. 209-214 ◽

Cited By ~ 1

Author(s):

Iara Janaína Fernandes ◽

Daiane Calheiro ◽

Emanuele Caroline Araújo dos Santos ◽

Roxane Oliveira ◽

Tatiana Louise Avila de Campos Rocha ◽

...

Keyword(s):

Rice Husk ◽

Rice Husk Ash ◽

Polymeric Materials ◽

Fluidized Bed Reactor ◽

Specific Weight ◽

High Energy ◽

Loss On Ignition ◽

X Ray Diffraction ◽

X Ray ◽

Different Sources

The use of rice husk ash (RHA) as filler in polymeric materials has been studied in different polymers. Research reported that RHA may successfully replace silica. The silica production process using ore demands high energy input and produces considerable amounts of waste. Therefore, the replacement of silica by RHA may be economically and environmentally advantageous, reducing environmental impact and adding value to a waste material. In this context, this study characterizes and compares RHA of different sources (moving grate and fluidized bed reactor) with commercially available silicas to assess performance as filler in polymeric materials. Samples were characterized by X-ray fluorescence, loss on ignition, X-ray diffraction, grain size, specific surface area, specific weight, and scanning electron microscopy. The results show that RHA may be used as a filler in several polymeric materials.

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