Synthesis of Rosin Acid Starch Catalyzed by Lipase

Rosin, an abundant raw material from pine trees, was used as a starting material directly for the synthesis of rosin acid starch. The esterification reaction was catalyzed by lipase (Novozym 435) under mild conditions. Based on single factor experimentation, the optimal esterification conditions were obtained as follows: rosin acid/anhydrous glucose unit in the molar ratio 2 : 1, reaction time 4 h at 45°C, and 15% of lipase dosage. The degree of substitution (DS) reaches 0.098. Product from esterification of cassava starch with rosin acid was confirmed by FTIR spectroscopy and iodine coloration analysis. Scanning electron microscopy and X-ray diffraction analysis showed that the morphology and crystallinity of the cassava starch were largely destroyed. Thermogravimetric analysis indicated that thermal stability of rosin acid starch decreased compared with native starch.

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Carboxyl graphene reinforced melamine-based polyamide nanocomposites

Journal of Thermoplastic Composite Materials ◽

10.1177/08927057211051411 ◽

2021 ◽

pp. 089270572110514

Author(s):

Himanshu V Madhad ◽

Dilip V Vasava

Keyword(s):

Electron Microscopy ◽

Decomposition Temperature ◽

Differential Scanning Calorimetric ◽

X Ray Diffraction ◽

One Pot ◽

X Ray ◽

Mild Conditions ◽

Thermal Stability Of ◽

Infrared Techniques ◽

Scanning Electron

Over the years, various types of techniques have been used for the synthesis of nanocomposites. In this work, melamine-based polyamide (PA) was synthesized using a one-pot polycondensation method under mild conditions. carboxyl graphene (CG)/PA nanocomposites (CGMPA) were prepared by CG nanofiller loadings of 1, 3, and 5 wt.% via delamination/adsorption approach. The prepared CGMPA nanocomposites were characterized using different analyses, such as Fourier transform infrared techniques (FTIR), field emission scanning electron microscopy (FESEM), X-ray diffraction (XRD), differential scanning calorimetric (DSC), and thermogravimetric analysis (TGA). The effects of the CG on the thermal properties of the CGMPA nanocomposites were significant. The results showed that the melting temperature (Tm) of neat PA and CGMPA were increased from 378°C to 393°C suggested better dispersion of CG in PA matrix. The decomposition temperature of PA was increased from 451°C to 463°C in CGMPA nanocomposites indicates the better thermal stability of PA matrix by addition of CG.

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Performance of B-Doped SrTiO3/ Ni Sheet for Supercapacitor Material Application

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.851.25 ◽

2020 ◽

Vol 851 ◽

pp. 25-31

Author(s):

Markus Diantoro ◽

Ahmad Al Ittikhad ◽

Thathit Suprayogi ◽

Nasikhudin ◽

Joko Utomo

Keyword(s):

Electrode Materials ◽

Solid State Reaction Method ◽

Raw Material ◽

Molar Ratio ◽

Sintering Process ◽

X Ray Diffraction ◽

Energy Storage Devices ◽

Xrd Pattern ◽

X Ray ◽

Storage Devices

The development of energy storage devices encourages the sustainability of research on basic materials of supercapacitor technology. SrTiO3 is one of metal oxide called as titanate alkali metal ATiO3 (A = Ba, Sr, Ca). This material shows an excellent dielectric constant, thus expected to be potential as raw material of supercapacitor. In this work, boron was used as a dopant on the SrTiO3 system to modify its local structure and enhance the electrical properties. Synthesis SrTi1-xBxO3 was carried out using a solid-state reaction method followed by the sintering process in various molar ratio. The microstructure of SrTi1-xBxO3 compound was identified by X-ray Diffraction with Cu-Kα. XRD pattern identified the presence of SrTi1-xBxO3 phase with a slight change in the lattice parameters. I-V measurement confirmed that the electrical conductivity increased gradually up to 16.04 Ω-1cm-1. For investigating their application for electrode materials, CV was employed and it presents that the specific capacitance and energy density of x = 0.08 were 5.488 Fg-1 and 0.110 Jg-1.

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Synthesis and Characterization of Phosphoric Silica Catalyst from Bamboo Leaves for Production of Triacetin

Journal of Biomimetics Biomaterials and Biomedical Engineering ◽

10.4028/www.scientific.net/jbbbe.54.129 ◽

2022 ◽

Vol 54 ◽

pp. 129-137

Author(s):

Renita Manurung ◽

Muhammad Dedi Anggreawan ◽

Alwi Gery Agustan Siregar

Keyword(s):

High Performance ◽

Catalytic Amount ◽

Raw Material ◽

Molar Ratio ◽

Solid Catalyst ◽

X Ray Diffraction ◽

X Ray ◽

Bamboo Leaves ◽

Bamboo Leaf Ash

In this research, the bamboo leaf shows promise as an alternative raw material for silica production. This study investigated the performance of heterogeneous catalyst prepared from silica derived bamboo leaf ash after that impregnated with phosphoric acid at ratio various. The catalyst was characterized by X-Ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscope Energy Dispersive X-Ray Spectroscopy (SEM-EDS), Brunauer Emmet Teller (BET) and Barrett, Joyner and Halenda (BJH) method and triacetin product analyzed by GC-MS. The optimum condition phosphoric silica catalyst was obtained at phosphoric silica molar ratio of 1:2 and employed in the acetylation of glycerol, respectively. As result, 24 % selectivity for triacetin was obtained in the presence of catalytic amount 5%, molar ratio 1:9 at 100 °C for 4 hours. Bamboo leaf derived phosphoric silica calcined showed high potential to be used as an easy to prepare and high-performance solid catalyst for industrial scale.

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Thermal behavior of electrospun gelatin and chitosan complex

Thermal Science ◽

10.2298/tsci1504323q ◽

2015 ◽

Vol 19 (4) ◽

pp. 1323-1326 ◽

Cited By ~ 3

Author(s):

Meng-Jie Qi ◽

Yong-Fang Qian ◽

Yu-Ping Zhao ◽

Wei Ju

Keyword(s):

Thermal Stability ◽

Thermal Behavior ◽

Raw Materials ◽

Raw Material ◽

X Ray Diffraction ◽

X Ray ◽

Crystalline Property ◽

Decomposition Stages ◽

Electrospun Gelatin ◽

Thermal Stability Of

This paper studied the thermal behavior of gelatin, chitosan, and their complex. Thermal stability was analyzed by thermogravimetric analysis, and the results showed that gelatin and chitosan raw materials exhibited two decomposition stages while as-electrospun nanofibrous mats had three decomposition stages. Moreover, chitosan raw material had better thermal stability than gelatin. However, its electrospun partner revealed its opposite trend. X-ray diffraction was used to analyze the crystalline property and the result showed that the crystallinity decreased due to the interaction with the solvents, and thus the thermal stability sharply decreased. In addition, incorporation of gelatin could improve the thermal stability of chitosan.

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Hydrothermal Synthesis of Bi4Ti3O12/TiO2 Composite

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.697.109 ◽

2016 ◽

Vol 697 ◽

pp. 109-112

Author(s):

Wei Zhao ◽

Nian Qi Liu ◽

Hong Xing Wang ◽

Yu Bo Zhang ◽

Shi Meng Zhang ◽

...

Keyword(s):

Electron Microscopy ◽

Methylene Blue ◽

Photocatalytic Activity ◽

Hydrothermal Synthesis ◽

Scan Electron Microscopy ◽

Raw Material ◽

Molar Ratio ◽

Hydrothermal Processing ◽

X Ray Diffraction ◽

X Ray

A hydrothermal processing technology was employed to synthesize Bi4Ti3O12/TiO2 composite by using TiO2 and Bi(NO3)3 as reactor precursors, and KOH as mineralizer. The microstructure and composition of the as-synthesized samples were characterized by X-ray diffraction (XRD), scan electron microscopy (SEM), and the photocatalytic activity was studied. The results showed that Bi/Ti molar ratio, mass of the KOH and the hydrothermal parameters play important roles on the morphology and activities of the photocatalyst. We could obtain composites with good morphology and better performance with 200 °C hydrothermal treatment for 12 h, 0.01 mol/L of KOH, and 1:2 of mole ratio of Bi/Ti, as well as using good crystalline TiO2 as the raw material. The as-prepared powder has a diameter of about 800nm, and the decolorized rate of methylene blue could reach 95 % after the UV-irradiation for 5 h.

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Effect of Hydrated Metal Salts on the Coordination Product of Cobalt(II) halide and PNP Type Ligand, 2,6-bis(di-tertbutylphosphinomethyl) pyridine

10.26434/chemrxiv.5851701 ◽

2018 ◽

Author(s):

Tasneem Siddiquee ◽

Abdul Goni

Keyword(s):

Metal Salts ◽

Molar Ratio ◽

Pincer Complexes ◽

Asymmetric Unit ◽

X Ray Diffraction ◽

Pincer Ligand ◽

Tetrahedral Geometry ◽

X Ray ◽

Distorted Tetrahedral Geometry ◽

Cobalt Center

Chemical treatment of CoX2. 6H2O (X = Cl, Br, I) with the potentially tridentate PNP pincer ligand 2,6-bis(di-tert-butylphosphinomethyl)pyridine in 1:1 molar ratio results in cobalt(II) halide-PNP pincer complexes. The effect of the hydrated metal source on molecular structure and geometry of the complexes was studied by single crystal X-ray diffraction analysis. The complexes are neutral and the cobalt center adopts a penta-coordinate system with potential atropisomerization. Within the unit cell there are two distinct molecules per asymmetric unit. One of the two phosphorus atoms in the PNP ligand was observed to be partially oxidized to phosphinoxide. Disorder in the structure reflects a mixture of square pyramidal and distorted tetrahedral geometry.

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An unusual reaction of a bridged triterpenoid α-diketone with acetic anhydride

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19912917 ◽

1991 ◽

Vol 56 (12) ◽

pp. 2917-2935 ◽

Cited By ~ 1

Author(s):

Eva Klinotová ◽

Václav Křeček ◽

Jiří Klinot ◽

Miloš Buděšínský ◽

Jaroslav Podlaha ◽

...

Keyword(s):

Acetic Acid ◽

Nmr Spectroscopy ◽

Acetic Anhydride ◽

Spectral Methods ◽

X Ray Diffraction ◽

X Ray ◽

Mild Conditions ◽

Condensation Products ◽

Unsaturated Lactones ◽

C Nmr

3β-Acetoxy-21,22-dioxo-18α,19βH-ursan-28,20β-olide (IIIa) reacts with acetic anhydride in pyridine under very mild conditions affording β-lactone IVa and γ-lactones Va and VIIa as condensation products. On reaction with pyridine, lactones Va and VIIa undergo elimination of acetic acid to give unsaturated lactones VIIIa and IXa, respectively. Similarly, the condensation of 20β,28-epoxy-21,22-dioxo-18α,19βH-ursan-3β-yl acetate (IIIb) with acetic anhydride leads to β-lactone IVb and γ-lactone Vb; the latter on heating with pyridine affords unsaturated lactone VIIIb and 21-methylene-22-ketone Xb. The structure of the obtained compounds was derived using spectral methods, particularly 1H and 13C NMR spectroscopy; structure of lactone IVa was confirmed by X-ray diffraction.

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Photocatalytic Reduction of CO2 to Methanol Using a Copper-Zirconia Imidazolate Framework

Catalysts ◽

10.3390/catal11030346 ◽

2021 ◽

Vol 11 (3) ◽

pp. 346

Author(s):

Sonam Goyal ◽

Maizatul Shima Shaharun ◽

Ganaga Suriya Jayabal ◽

Chong Fai Kait ◽

Bawadi Abdullah ◽

...

Keyword(s):

Photoelectron Spectroscopy ◽

Catalyst Support ◽

Oxidation Potential ◽

Molar Ratio ◽

X Ray Diffraction ◽

X Ray ◽

Molar Ratios ◽

Optimum Parameters ◽

Reduction Of Co2 ◽

Enhanced Yield

A set of novel photocatalysts, i.e., copper-zirconia imidazolate (CuZrIm) frameworks, were synthesized using different zirconia molar ratios (i.e., 0.5, 1, and 1.5 mmol). The photoreduction process of CO2 to methanol in a continuous-flow stirred photoreactor at pressure and temperature of 1 atm and 25 °C, respectively, was studied. The physicochemical properties of the synthesized catalysts were studied using X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and photoluminescence (PL) spectroscopy. The highest methanol activity of 818.59 µmol/L.g was recorded when the CuZrIm1 catalyst with Cu/Zr/Im/NH4OH molar ratio of 2:1:4:2 (mmol/mmol/mmol/M) was employed. The enhanced yield is attributed to the presence of Cu2+ oxidation state and the uniformly dispersed active metals. The response surface methodology (RSM) was used to optimize the reaction parameters. The predicted results agreed well with the experimental ones with the correlation coefficient (R2) of 0.99. The optimization results showed that the highest methanol activity of 1054 µmol/L.g was recorded when the optimum parameters were employed, i.e., stirring rate (540 rpm), intensity of light (275 W/m2) and photocatalyst loading (1.3 g/L). The redox potential value for the CuZrIm1 shows that the reduction potential is −1.70 V and the oxidation potential is +1.28 V for the photoreduction of CO2 to methanol. The current work has established the potential utilization of the imidazolate framework as catalyst support for the photoreduction of CO2 to methanol.

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Characterization and A Preliminary Study of TiO2 Synthesis from Lampung Iron Sand

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.849.113 ◽

2020 ◽

Vol 849 ◽

pp. 113-118

Author(s):

Yayat Iman Supriyatna ◽

Slamet Sumardi ◽

Widi Astuti ◽

Athessia N. Nainggolan ◽

Ajeng W. Ismail ◽

...

Keyword(s):

Food Packaging ◽

Xrd Analysis ◽

Major Elements ◽

Raw Material ◽

Solid Residue ◽

X Ray Diffraction ◽

X Ray ◽

Leaching Solution ◽

Ti Content

The purpose of this study is to characterize Lampung iron sand and to conduct preliminary experiments on the TiO2 synthesis which can be used for the manufacturing of functional food packaging. The iron sand from South Lampung Regency, Lampung Province that will be utilized as raw material. The experiment was initiated by sieving the iron sand on 80, 100, 150, 200 and 325 mesh sieves. Analysis using X-Ray Fluorescence (XRF) to determine the element content and X-Ray Diffraction (XRD) to observe the mineralization of the iron sand was conducted. The experiment was carried out through the stages of leaching, precipitation, and calcination. Roasting was applied firstly by putting the iron sand into the muffle furnace for 5 hours at a temperature of 700°C. Followed by leaching using HCl for 48 hours and heated at 105°C with a stirring speed of 300 rpm. The leaching solution was filtered with filtrate and solid residue as products. The solid residue was then leached using 10% H2O2 solution. The leached filtrate was heated at 105°C for 40 minutes resulting TiO2 precipitates (powder). Further, the powder was calcined and characterized. Characterization of raw material using XRF shows the major elements of Fe, Ti, Mg, Si, Al and Ca. The highest Ti content is found in mesh 200 with 9.6%, while iron content is about 80.7%. While from the XRD analysis, it shows five mineral types namely magnetite (Fe3O4), Rhodonite (Mn, Fe, Mg, Ca) SiO3, Quart (SiO2), Ilmenite (FeOTiO2) and Rutile (TiO2). The preliminary experiment showed that the Ti content in the synthesized TiO2 powder is 21.2%. The purity of TiO2 is low due to the presence of Fe metal which is dissolved during leaching, so that prior to precipitation purification is needed to remove impurities such as iron and other metals.

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Sedimentary Clays as Geopolymer Precursor

International Journal of Engineering Research in Africa ◽

10.4028/www.scientific.net/jera.39.97 ◽

2018 ◽

Vol 39 ◽

pp. 97-111

Author(s):

F. Mostefa ◽

Nasr Eddine Bouhamou ◽

H.A. Mesbah ◽

Salima Aggoun ◽

D. Mekhatria

Keyword(s):

Sodium Hydroxide ◽

Mineralogical Composition ◽

Cementitious Materials ◽

Raw Material ◽

X Ray Diffraction ◽

Calcination Time ◽

Calorimetric Analysis ◽

X Ray ◽

Before And After ◽

Mechanical Performances

This work aims to study the feasibility of making a geopolymer cement based on dredged sediments, from the Fergoug dam (Algeria) and to evaluate their construction potential particularly interesting in the field of special cementitious materials. These sediments due to their mineralogical composition as aluminosilicates; are materials that can be used after heat treatment. Sedimentary clays were characterized before and after calcination by X-ray diffraction, ATG / ATD, spectroscopy (FTIR) and XRF analysis. The calcination was carried out on the raw material sieved at 80 μm for a temperature of 750 ° C, for 3.4 and 5 hours. The reactivity of the calcined products was measured using isothermal calorimetric analysis (DSC) on pastes prepared by mixing an alkaline solution of sodium hydroxide (NaOH) 8 M in an amount allowing to have a Na / Al ratio close to 1 (1: 1). Also, cubic mortar samples were prepared with a ratio L / S: 0.8, sealed and cured for 24 hours at 60 ° C and then at room temperature until the day they were submited to mechanical testing. to check the extent of geopolymerization. The results obtained allowed to optimize the calcination time of 5 hours for a better reactivity of these sediments, and a concentration of 8M of sodium hydroxide and more suitable to have the best mechanical performances.

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