Hemicelluloses Separation from Black Liquor

2012 ◽  
Vol 518-523 ◽  
pp. 589-593
Author(s):  
Yu Xin Liu ◽  
Bing Sun ◽  
Yong Zhu ◽  
Tong Zai Li
Keyword(s):  
Organic Solvents ◽  
Black Liquor ◽  
Precipitation Method ◽  
Separation System ◽  
Ft Ir ◽  
Charge Temperature ◽  
Mixed Alcohols

The black liquor from NaOH-AQ pulping of bagasse was treated by conventional alcohol precipitation method to separate hemicelluloses. In the system of alcohol/methanol, some parameters which may affect the hemicelluloses precipitation were discussed, such as mixed alcohols charge, temperature, pH and time. The obtained hemicelluloses were analyzed by FT-IR. The results showed that compared with conventional separation system of hemicelluloses by alcohol, when the Valcohol: Vmethanolwas 5:5 and pH was 4.5 at 45°C, the consumption of alcohols was decreased by 17% to 30%. Moreover, the addition of flocculants of PAC/A PAM in the process of hemicelluloses separation, the consumption of organic solvents would be further decreased.

Solubility Enhancement of Poorly Water-Soluble Antifungal Drug Acyclovir by Nanocrystal Formulation Approach

2018 ◽  
Vol 11 (2) ◽  
pp. 4036-4042
Author(s):  
Prakash Goudanavar ◽  
Ankit Acharya ◽  
Vinay C.H
Keyword(s):  
Chemical Interaction ◽  
Research Work ◽  
Antiviral Drug ◽  
In Vitro Release ◽  
Oral Route ◽  
Water Soluble ◽  
Precipitation Method ◽  
Dsc Studies ◽  
Ft Ir

Administration of an antiviral drug, acyclovir via the oral route leads to low and variable bioavailability (15-30%). Therefore, this research work was aimed to enhance bioavailability of acyclovir by nanocrystallization technique. The drug nanocrystals were prepared by anti-solvent precipitation method in which different stabilizers were used. The formed nanocrystals are subjected to biopharmaceutical characterization including solubility, particle size and in-vitro release. SEM studies showed nano-crystals were crystalline nature with sharp peaks. The formulated drug nanocrystals were found to be in the range of 600-900nm and formulations NC7 and NC8 showed marked improvement in dissolution velocity when compared to pure drug, thus providing greater bioavailability. FT-IR and DSC studies revealed the absence of any chemical interaction between drug and polymers used. 

Synthesis of Silica Modified Large-Sized Hydroxyapatite Whiskers by a Hydrothermal Co-Precipitation Method

2015 ◽  
Vol 645-646 ◽  
pp. 1339-1344 ◽  
Author(s):  
Yan Ting Yin ◽  
Qing Hua Chen ◽  
Ting Ting Yan ◽  
Qing Hua Chen
Keyword(s):  
Bone Repair ◽  
Ethanol Solution ◽  
Morphological Properties ◽  
Precipitation Method ◽  
X Ray Diffraction ◽  
X Ray ◽  
New Type ◽  
Ft Ir ◽  
Co Precipitation ◽  
Surface Modified

The objective of this study was to develop a novel silica modified large-sized hydroxyapatite whiskers with improved properties for use in bone repair applications. Large-sized whiskers with a mean length of 250μm were obtained by a hydrothermal co-precipitation method at 150°C, 7.5Mpa in high-pressure reactor. Silica modified hydroxyapatite whiskers were prepared by dissolving TEOS in ethanol solution, then sintering with hydroxyapatite. The compositional and morphological properties of prepared whiskers were studied by means of x-ray diffraction (XRD), Fouier transform infrared (FT-IR), scanning electron microscopy (SEM). The results indicated the evidence of nanosilicon dioxide particles on the surface of HAP whiskers. The size of nanosilicon dioxide particles depends on dropping and stirring rate. Hence, this new type of silica modified large-sized hydroxyapatite whiskers is a valuable candidate for biomedical applications.Key words: hydroxyapatite, hydrothermal co-precipitation, surface modified, whiskers

Effect of Mn Dopant on Lattice Parameters and Band Gap Energy of Semiconductor ZnO Nanoparticles

2013 ◽  
Vol 829 ◽  
pp. 784-789 ◽  
Author(s):  
Mahmoud Zolfaghari ◽  
Mahshid Chireh
Keyword(s):  
Band Gap ◽  
Zno Nanoparticles ◽  
Room Temperature ◽  
Lattice Parameters ◽  
Memory Storage ◽  
Precipitation Method ◽  
High Electron ◽  
Gap Energy ◽  
Wide Range ◽  
Ft Ir

ZnO belongs to the II-VI semiconductor group with a direct band-gap of 3.2-3.37 eV in 300K and a high exciton binding energy of 60 meV. It has good transparency, high electron mobility, wide, and strong room-temperature luminescence. These properties have many applications in a wide area of emerging applications. Doping ZnO with the transition metals gives it magnetic property at room temperature hence making it multifunctional material, i.e. coexistence of magnetic, semiconducting and optical properties. The samples can be synthesized in the bulk, thin film, and nanoforms which show a wide range of ferromagnetism properties. Ferromagnetic semiconductors are important materials for spintronic and nonvolatile memory storage applications. Doping of transition metal elements into ZnO offers a feasible means of tailoring the band gap to use it as light emitters and UV detector. As there are controversial on the energy gap value due to change of lattice parameters we have synthesized Mn-doped ZnO nanoparticles by co-precipitation method with different concentrations to study the effect of lattice parameters changes on gap energy. The doped samples were studied by XRD, SEM, FT-IR., and UV-Vis. The XRD patterns confirm doping of Mn into ZnO structure. As Mn concentrations increases the peak due to of Mn impurity in FT-IR spectra becomes more pronounces hence confirming concentrations variation. We find from UV-Vis spectra that the gap energy due to doping concentration increases due to the Goldschmidt-Pauling rule this increase depends on dopant concentrations and increases as impurity amount increases.

scholarly journals Diverse resourcing of Nerium indicum leaves for bio-utilization

2020 ◽  
Vol 24 (3 Part A) ◽  
pp. 1785-1793
Author(s):  
Dongli Ma ◽  
Yuanyuan Chen ◽  
Yong Lai ◽  
Zanpei Zhang ◽  
Ximei Li ◽  
...  
Keyword(s):  
Organic Solvent ◽  
Organic Solvents ◽  
Raw Materials ◽  
Chemical Constituents ◽  
Food Additives ◽  
Ornamental Plant ◽  
Bioactive Ingredients ◽  
Ft Ir ◽  
Medicinal Properties ◽  
Alcohol Benzene

Nerium indicum is an ornamental plant that is widely distributed in tropical and subtropical regions wordwide. It has toxic and medicinal properties which is closely related to the bioactive ingredients contained in Nerium indicum. In our research, the leaves of Nerium indicum was used as raw materials to study the chemical constituents and their effects. The chemical constituents of the leaves were analyzed by FT-IR and GC-MS with alcohol, benzene and acetone as organic solvents. A total of 73 compounds were obtained by acetone organic solvent, 25 compounds were extracted from benzene and 146 compounds were obtained from alcohol. Rich bioactive and bioenergy components were found in all three kinds of extract, suggesting that Nerium indicum leaves are of great significance for the diverse resourcing of bio-utilization including biomedicine, bioenergy, aroma, food additives.

scholarly journals A Novel Strong Cyan Luminescence Emission of Tb2O3 Particles

2021 ◽  
Author(s):  
Fatma Unal
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Ammonium Carbonate ◽  
Precipitation Method ◽  
X Ray Diffraction ◽  
Terbium Oxide ◽  
X Ray ◽  
Ft Ir ◽  
Pl Emission ◽  
Scanning Electron

Abstract Terbium oxide (Tb2O3) particles (NPs) were synthesized by precipitation method using ammonium carbonate as precipitation agent. Effects of precursor molarity (0.1, 0.15 and 0.2 M) on photoluminescence (PL) behaviour of the NPs were investigated. The presence of the Tb2O3 phase was confirmed by X-Ray Diffraction (XRD) and Fourier-transform infrared spectroscopy (FT-IR) analyses. Morphological investigations of the produced powders were made by Field Emission Gun-Scanning Electron Microscopy (FEG-SEM). It showed that the morphology of Tb2O3 particles transformed from the nanograin chain to bundles morphology of rod-like as the amount of precursor molarity increased. Emission spectrum were investigated by Photoluminescence (PL) Spectroscopy. All the Tb2O3 particles exhibited the strongest peak at 493 nm ascribed to 5D4-7F6 (magnetic dipole (MD), C2) transition. The increase in the number of C2 sites released from the MD transition with the increase of the precursor molarity caused a negative increase in the b* (yellowness/blueness of the emission) value in the CIE diagram, indicating that the colour shifted to the blue region. The Tb2O3 particles produced by the precipitation method exhibited novel strong cyan colour and the PL emission intensity increased with increasing molarity.

scholarly journals Final technical report. In-situ FT-IR monitoring of a black liquor recovery boiler

1999 ◽  
Author(s):  
James Markham ◽  
Joseph Cosgrove ◽  
David Marran ◽  
Jorge Neira ◽  
Chad Nelson ◽  
...  
Keyword(s):  
Black Liquor ◽  
Technical Report ◽  
Ft Ir ◽  
Recovery Boiler ◽  
Black Liquor Recovery Boiler

Synthesis of Magnetic Modified Organobentonite as Adsorbent for Degradation of Orange II

2013 ◽  
Vol 838-841 ◽  
pp. 2306-2309
Author(s):  
Guang Hua Wang ◽  
Kun Chen ◽  
Wen Bing Li ◽  
Dong Wan ◽  
Qin Hu ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Reaction Medium ◽  
Precipitation Method ◽  
Basal Spacing ◽  
Orange Ii ◽  
X Ray Diffraction ◽  
X Ray ◽  
Ft Ir ◽  
Co Precipitation ◽  
Scanning Electron

Magnetic modified organobentonite (Fe3O4/CTAB–Bent) was synthesized by chemical co-precipitation method in which CTAB–Bent was firstly achieved via ion–exchange.The composite materials have been characterized by powder X–ray diffraction (XRD), Fourier transform infrared spectroscopy (FT–IR) and Scanning electron microscopy (SEM) . The results revealed that basal spacing of bentonite was increased through organic modification and the Fe3O4 particles synthesized which covering the surfaces of bentonite .Compared with natural bentonite, the adsorption capacity of Fe3O4/CTAB–Bent for Orange II was greatly enhanced and can be easily separated from the reaction medium by an external magnetic field after the treatment.

scholarly journals Hydroxyapatite-ciprofloxacin delivery system: Synthesis, characterisation and antibacterial activity

2018 ◽  
Vol 68 (2) ◽  
pp. 129-144 ◽  
Author(s):  
Maria-Viorica Ciocilteu ◽  
Andreea Gabriela Mocanu ◽  
Adriana Mocanu ◽  
Catalin Ducu ◽  
Oana Elena Nicolaescu ◽  
...  
Keyword(s):  
Antibacterial Activity ◽  
Chemical Precipitation ◽  
Precipitation Method ◽  
Synthesis Process ◽  
Diffusion Controlled ◽  
Ft Ir ◽  
Inhibition Zones ◽  
Bacterial Growth Inhibition ◽  
Local Release

Abstract The main objective of this study was to synthesize hydroxyapatite-ciprofloxacin composites using a chemical precipitation method and to evaluate the properties and in vitro release profile of the drug from the hydroxyapatite-ciprofloxacin composites. Composite characterization was achieved by FT-IR, XRD and DLS. Ciprofloxacin determination was accomplished by HPLC, resulting in good incorporation efficiency of the drug (18.13 %). The in vitro release study (Higuchi model C = K t1/2 and Ritger-Peppas model, C = K t0.6) showed a diffusion-controlled mechanism. The antibacterial activity showed that the bacterial growth inhibition zones were approximately equal for the synthesis composites and for the mechanical mixture on the Staphylococcus aureus germ. The use of hydroxyapatite, which is a biocompatible, bioactive and osteoconductive material, with ciprofloxacin, which has good antibacterial activity in this composite, makes it suitable for the development of bone grafts. Furthermore, the synthesis process allows a slow local release of the drug.

scholarly journals Effect of La2O3 as a Promoter on the Pt,Pd,Ni/MgO Catalyst in Dry Reforming of Methane Reaction

Catalysts ◽  
2020 ◽  
Vol 10 (7) ◽  
pp. 750 ◽  
Author(s):  
Ali M. A. Al-Najar ◽  
Faris A. J. Al-Doghachi ◽  
Ali A. A. Al-Riyahee ◽  
Yun Hin Taufiq-Yap
Keyword(s):  
Carbon Deposition ◽  
Dry Reforming ◽  
Dry Reforming Of Methane ◽  
Precipitation Method ◽  
Gravimetric Analysis ◽  
Bet Method ◽  
Spent Catalysts ◽  
Ft Ir ◽  
Co Precipitation ◽  
Surfactant Assisted

Pt,Pd,Ni/MgO, Pt,Pd,Ni/Mg0.97La3+0.03O, Pt,Pd,Ni/Mg0.93La3+0.07O, and Pt,Pd,Ni/Mg0.85La3+0.15O (1% of each of the Ni, Pd, and Pt) catalysts were prepared by a surfactant-assisted co-precipitation method. Samples were characterized by the XRD, XPS, XRF, FT-IR, H2-TPR, TEM, the Brunauer–Emmett–Teller (BET) method, and TGA and were tested for the dry reforming of methane (DRM). TEM and thermal gravimetric analysis (TGA) methods were used to analyze the carbon deposition on spent catalysts after 200 h at 900 °C. At a temperature of 900 °C and a 1:1 CH4:CO2 ratio, the tri-metallic Pt,Pd,Ni/Mg0.85La3+0.15O catalyst with a lanthanum promoter showed a higher conversion of CH4 (85.01%) and CO2 (98.97%) compared to the Ni,Pd,Pt/MgO catalysts in the whole temperature range. The selectivity of H2/CO decreased in the following order: Pt,Pd,Ni/Mg0.85La3+0.15O > Pt,Pd,Ni/Mg0.93La3+0.07O > Pt,Pd,Ni/Mg0.97La3+0.03O > Ni,Pd,Pt/MgO. The results indicated that among the catalysts, the Pt,Pd,Ni/Mg0.85La23+0.15O catalyst exhibited the highest activity, making it the most suitable for the dry reforming of methane reaction.

Effect of Sintering Temperature on Carbonated Hydroxyapatite Derived from Common Cockle Shells (Cerastodermaedule): Composition and Crystal Characteristics

2019 ◽  
Vol 818 ◽  
pp. 37-43
Author(s):  
Rosita Wati ◽  
Yusril Yusuf
Keyword(s):  
Fourier Transform ◽  
Energy Dispersive Spectrometry ◽  
Sintering Temperature ◽  
Precipitation Method ◽  
Carbonated Hydroxyapatite ◽  
X Ray ◽  
Carbonate Ion ◽  
Eds Analysis ◽  
Ft Ir ◽  
Common Cockle

Incorporation carbonate ion to hydroxyapatite (HAp) structure, known as carbonated hydroxyapatite (CHAp) is reported to reduce crystallinity, increase the solubility rate, and increase bioactivity. Sintered CHAp material is interesting because it may have a better biological response.CHAp derived from common cockle (Cerastoderma edule) shell have produced by precipitation method. This study aimed to investigate the effect of sintering temperature to compositon and crystal characteristics of CHAp. CHAp powder was sintered at 400, 600, and 800°C in air atmosphere.CHApas-preparedand sintered samples were analyzed using Energy Dispersive Spectrometry (EDS), Fourier Transform Infrared (FT-IR), and X-ray Diffractometer (XRD).EDS analysis showed that the Ca/P ratio of powder CHAp was around 1.67-1.94 (greater than the Ca/P ratioof HAp). For increasing of sintering temperature, carbonate and water content decreased, crystallinity and crystallite size increased.

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