Effect of Temperature on the Yield of Lignin Extracted Using Microwave-Assisted Acetosolv from Empty Fruit Bunch Fibers

2020 ◽  
Vol 981 ◽  
pp. 240-244
Author(s):  
Muhammad Nor Arifin Yaakob ◽  
Rasidi Roslan ◽  
Nurjannah Salim ◽  
Siti Noor Hidayah Mustapha ◽  
Sarani Zakaria ◽  
...  

Acetosolv technique is considered as one of the best alternative way to extract technical lignin from biomass as it has high efficiency and environmentally friendly. In this study, microwave-assisted acetosolv technique were used to extract lignin from oil palm empty fruit bunch (OPEFB) in the presence of 3% sulfuric acid catalyst reacted at various temperature. The yield of the extracted acetosolv lignin were calculated using modified Technical Association of the Pulp and Paper Industry biomass composition analysis (TAPPI) method. The result showed that, as the temperature increased from 90 to 110 °C, the yield of lignin extracted also increase from 43.07 to 76.98%. The presence of guaiacyl and p-coumarate indicates the presence of active sites at C-3 and C-5 of aromatic ring for polymerization reactions. Scanning Electron Microscopy images showed that removal of lignin are intensified as the microwave-assisted acetosolv temperature increased.

2021 ◽  
Vol 112 ◽  
pp. 110801
Author(s):  
Alif Syafiq Kamarol Zaman ◽  
Tong Ling Tan ◽  
Yamuna A/P Chowmasundaram ◽  
Norhanisah Jamaludin ◽  
Amir Reza Sadrolhosseini ◽  
...  

Catalysts ◽  
2020 ◽  
Vol 11 (1) ◽  
pp. 47
Author(s):  
Oleksandr Shtyka ◽  
Viktar Shatsila ◽  
Radoslaw Ciesielski ◽  
Adam Kedziora ◽  
Waldemar Maniukiewicz ◽  
...  

The photocatalytic activity of TiO2 depends on numerous factors, such as the chemical potential of electrons, charge transport properties, band-gap energy, and concentration of surface-active sites. A lot of research has been dedicated to determining the properties that have the most significant influence on the photocatalytic activity of semiconductors. Here, we demonstrated that the activity of TiO2 in the gas-phase reduction of CO2 is governed mainly by the desorption rate of the reaction intermediates and final products. This indicates that the specific surface area of TiO2 and binding strength of reaction intermediates and products are the main factors affecting the photocatalytic activity of TiO2 in the investigated process. Additionally, it was shown that rutile exhibits higher photocatalytic activity than anatase/rutile mixtures mainly due to its high efficiency in the visible portion of the electromagnetic spectrum.


2005 ◽  
Vol 2005 (11) ◽  
pp. 733-735 ◽  
Author(s):  
Nemai C. Ganguly ◽  
Sanjoy Dutta ◽  
Mrityunjoy Datta ◽  
Prithwiraj De

Predominant ortho-selective mononitration of low-melting and liquid phenols and hydroxycoumarins in moderate to high yields has been accomplished upon grinding with solid cerium (IV) ammonium nitrate (CAN). Microwave-assisted expeditious CAN-mediated nitration of relatively high melting phenols and hydroxycoumarins with high efficiency and selectively under solvent-free conditions has been also developed to address the problems of sluggishness and low yield for these reluctant substrates.


2015 ◽  
Vol 74 (11) ◽  
Author(s):  
Riry Wirasnita ◽  
Tony Hadibarata ◽  
Abdull Rahim Mohd Yusoff ◽  
Zainab Mat Lazim

An oil palm empty fruit bunch-derived activated carbon has been successfully produced by chemical activation with zinc chloride and without chemical activation. The preparation was conducted in the tube furnace at 500oC for 1 h. The surface structure and active sites of activated carbons were characterized by means of Fourier transform infrared spectrometry and field emission scanning electron microscopy. The proximate analysis including moisture content, ash content, bulk density, pH, and pH at zero charge was conducted to identify the psychochemical properties of the adsorbent. The results showed that the zinc chloride-activated carbon has better characteristics compared to the carbon without chemical activation.  


Molecules ◽  
2018 ◽  
Vol 23 (12) ◽  
pp. 3143 ◽  
Author(s):  
Li Jia ◽  
Lingling Fu ◽  
Xiaoyan Wang ◽  
Wenzhi Yang ◽  
Hongda Wang ◽  
...  

The analytical platform UHPLC/Q-Orbitrap-MS offers a solution to quality investigation of TCM with high definiteness. Using Erzhi Pill (EZP) as a case, we developed UHPLC/Q-Orbitrap-MS based approaches to achieve systematic multicomponent identification and rapid authentication. Comprehensive multicomponent characterization of EZP was performed by negative/positive switching data-dependent high-energy collision-induced dissociation-MS2 (HCD-MS2) after 25 min chromatographic separation. By reference compounds comparison, elemental composition analysis, fragmentation pathways interpretation, and retrieval of an in-house library, 366 compounds were separated and detected from EZP, and 96 thereof were structurally characterized. The fingerprints of two component drugs (Ligustri Lucidi Fructus, LLF; Ecliptae Herba, EH) for EZP were analyzed under the same LC-MS condition by full scan in negative mode. In combination with currently available pharmacological reports, eight compounds were deduced as the ‘identity markers’ of EZP. Selective ion monitoring (SIM) of eight marker compounds was conducted to authenticate six batches of EZP samples. Both LLF and EH could be detected from all EZP samples by analyzing the SIM spectra, which could indicate their authenticity. Conclusively, UHPLC/Q-Orbitrap-MS by rapid polarity switching could greatly expand the potency of untargeted profiling with high efficiency, and SIM of multiple chemical markers rendered a practical approach enabling the authentication of TCM formulae.


2018 ◽  
Vol 2018 ◽  
pp. 1-10 ◽  
Author(s):  
Ali Alsalme ◽  
Aliyah A. Alsharif ◽  
Hamda Al-Enizi ◽  
Mujeeb Khan ◽  
Saad G. Alshammari ◽  
...  

Supported heteropoly acids are an interesting class of solid acid catalysts which possess flexible structure and super acidic properties essentially required for the oil-based biodiesel production. In this study, a series of catalysts containing 25 wt.% of heteropolytungstate (HPW) supported on various clays or SiO2 were prepared, and their catalytic efficiency was evaluated for esterification of acetic acid with heptanol. The as-prepared catalysts were characterized by various techniques including FT-IR spectroscopy, thermogravimetric analysis, X-ray diffraction, scanning electron microscopy, and BET. The catalytic efficiency of both bulk and supported HPW catalysts for the esterification activity strongly depends on the type of support and amount of catalyst; the bulk HPW catalyst and the catalyst supported by kaolinite with 25 wt.% of HPW exhibited highest activity. In order to study the effect of temperature on conversion, all the catalysts were subjected to different reaction temperatures. It was revealed that esterification activity of both bulk and supported HPW catalysts strongly depends upon the temperature variations of the reaction. Besides, the effect of leaching of active sites on the catalysts performance for biodiesel production was also evaluated by inductively coupled plasma studies (ICP). The kaolinite-supported catalyst (25% HPW/kaolinite) demonstrated higher amount of leaching which is also confirmed by the significant decrease in its catalytic activity when it is used for the second time. However, the higher activity demonstrated by HPW/kaolinite maybe because of some homogeneous reaction indicating a weak catalyst support interaction (WCSI) resulting in the leaching of the catalyst during the test. Furthermore, the effects of other reaction variables such as catalyst loading and reaction time on the conversion of acetic acid were also studied.


Sign in / Sign up

Export Citation Format

Share Document