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    Comparison of lignin yield from sugarcane bagasse pellets using liquid hot water and ionic liquid pretreatment methods
    (2019) Gnana, Gueh Charles; Deenadayalu, Nirmala
    In this research work, lignin yield from sugarcane bagasse pellets (SBP) was investigated after treatment of sugar cane bagasse with liquid hot water (LHW) and enzymatic hydrolysis followed by ionic liquids (ILs) and only ionic liquids pretreatment methods. In the LHW and ionic liquid methods, the SBP were first treated with LHW at 200 °C, for 30 minutes in a suitable reactor, for removal of hemicellulose. The complex cellulignin residue was treated separately with either of two ionic liquids namely: 1-ethyl-3- methylimidazolium acetate ([Emim][OAc]) or 1-butyl-3- methylimidazolium hydrogen sulphate ([Bmim][HSO4]), using microwave digestion at varying time intervals. Theionicliquidmethodinvolvedthepretreatmentofsugarcanebagasse pelletswith either 1-ethyl-3-methylimidazolium acetate or 1-butyl-3-methylimidazolium hydrogen sulphate followed by microwave digestion at varying time intervals. Ultraviolet (UV) spectroscopy at a wavelength of 280 nm was used as a tool for quantification of lignin. The different functional groups of the extracted lignin were confirmed using attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy. Thermogravimetric analysis (TGA) provided information on thermal characteristics of the extracted lignin. In addition to material characterization, mixed factorial ANOVA was performed to compare the extracted lignin yield using the LHW and IL and the ionic liquid pretreatment methods. High performance liquid chromatography (HPLC) was used to identify the C5 sugars in the hydrolysate after LHW pretreatment. X-ray diffraction (XRD) was used to identify cellulose peaks of cellulignin and SBP and ILs treated samples. The results indicated that the lignin yield from sugarcane bagasse pellets after liquid hot water treatment and enzymatic hydrolysis was 37.8 % (m/v). The highest percentage yield of lignin extracted from the complex cellulignin (LHW and IL) was found to be 68.00 % (m/v) and 32.04 % (m/v) for [Emim][OAc] and [Bmim][HSO4], respectively for the optimized reaction time of 10 minutes. However, 67.25 % (m/v) and 48.94 % (m/v) of the extracted lignin were obtained for the pretreated SBP with [Emim][OAc] and [Bmim][HSO4], respectively for a reaction time of 20 minutes. This comparative study revealed that, there is no significant difference between the yield of lignin extracted from the complex cellulignin (68.00%) and sugarcane bagasse pellets (67.25 %).The sugarcane bagasse pellets is the preferred method since it doesn’t require high energy input.
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    Efficient catalytic activity of ionic liquid-supported NiFe2O4 magnetic nanoparticle doped Titanium Dioxide nano-composite
    (IJCEA, 2016-12) Vasanthakumar, Arumugam; Redhi, Gan G.; Gengan, Robert Moonsamy
    In this work the author disclose an effective and environment-friendly approach to the preparation of an ionic liquid supported, magnetic nanoparticle doped titanium oxide nanocomposite. The novel ionic liquid N-(2′, 3′-epoxypropyl)-N-methyl-2- pyrrolidonium salicylate was first synthesized and characterized by 1H-NMR, 13C-NMR, elemental Analysis and FTIR. It was subsequently used for the preparation of a composite material by traditional protocols. This ionic liquid is able to connect the NiFe2O4 magnetic nanoparticles with titanium dioxide via strong ionic liquid interactions. The composite was characterized by FT-IR, Scanning Electron Microscopy (SEM), Energy Dispersive X-Ray (EDS) analysis, Transmission Electron Microscopy (TEM), High-Resolution Transmission Electron Microscopy (TEM) and Diffraction studies (DF). The catalytic activities of these composites were assessed by the reduction of nitro aniline with the aid of UV spectroscopy. Furthermore, the composite material was easily recovered and re-used with negligible loss of its catalytical activity.
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    Densities and excess molar volume for the ternary systems (1-Butyl-3-methylimidazolium methyl sulphate + Nitromethane + Methanol or Ethanol or 1-Propanol) at T = (303.15 and 313.15) K
    (SA Epublications, 2013) Bahadur, Indra; Deenadayalu, Nirmala
    The densities of the ternary systems containing the ionic liquid 1-butyl-3-methylimidazolium methyl sulphate ([BMIM]+[MeSO4]–) were determined. The ternary systems studied were ([BMIM]+[MeSO4]– + nitromethane + methanol or ethanol or 1-propanol) at the temperatures (303.15 and 313.15) K. The ternary excess molar volumes were calculated from the experimental densities at each temperature, being negative for all mole fractions of the ionic liquid. The minimum ternary excess molar volumes increase with an increase in temperature for the systems ([BMIM]+[MeSO4]– + nitromethane + methanol or ethanol), and decrease for the system ([BMIM]+ [MeSO4]–+ nitromethane + 1-propanol). The results are interpreted in terms of the alcohol chain length and the intermolecular interactions.