Summary
We present a protocol for the synthesis of C5 sugars (xylose and arabinose) from a renewable non-edible lignocellulosic biomass (i.e., jute) with the presence of Brønsted acidic ionic liquids (BAILs) as the catalyst in water. The BAILs catalyst exhibited better catalytic performance than conventional mineral acid catalysts (H2SO4 and HCl).
Transcript
The overall goal of this novel method is to convert pentosan present in jute biomass into C5 sugars using acidic ionic liquids.This method can also be used for the determination of pentosan concentrations present in the jute biomass.This measure enables the synthesis of C5 sugars from various low biomass in acerous media using a catalytic amount of acidic ionic liquid.The main advantage of this technique is that the acidic ionic liquid used for the conversion of jute biomass performs better compared to mineral acids.First have 7.625 millimoles of 1, 3-propane sultone to a cooled 50 milliliter round bottom flask and seal the flask with a rubber septum.Using a one milliliter syringe, slowly add 7.625 moles of 1-methylimidazole to the flask over 10 minutes at zero degrees Celsius.For the successful synthesis of this acidic ionic liquid the addition of 1, 3-propane sultone and 1-methylimidazole should be performed very slowly at zero degrees Celsius.Following this add 15 milliliters of dry toluene to the reaction mixture.After removing the ice water bath, reflux the reaction mixture or 16 hours at 120 degrees Celsius to obtain the solid zwitterion.After the reaction is complete separate the zwitterion from toluene using vacuum filtration.Then wash the zwitterion with 40 milliliters of toluene.For drying the zwitterion, set the temperature of an oven to 80 degrees celsius.Once the desired temperature is reached, transfer the zwitterion to a Petri dish and place in the oven to dry for four hours.After drying, transfer the dried zwitterion to a round bottom flask and add sulfuric acid using a 1, 000 microliter micropipet.Connect the round bottom flask to a reflux condenser.Then, heat the mixture under stirring at 110 degrees Celsius for 12 hours to obtain the desired ionic liquid.To prepare on liter of blank solution, add 10 milligrams of the para-nitroaniline indicator and distilled water to a 1 liter volumetric flask.Manually shake the solution thoroughly for two minutes, and set aside for one hour to fully mix the para-nitroaniline in water.To prepare the sample solution add 1.59 millimoles of H+ion of the acid catalyst to 50 milliliters of para-nitroaniline indicator solution and manual shake the mixture thoroughly for two minutes.Now perform a UV measurement of the blank and sample solutions and determine the maximum absorbance of para-nitroaniline.Add one gram of dried jute biomass and 15 milliliters of 72 weight percent sulfuric acid to a 50 milliliter vial.Stir the mixture on a hot plate at 30 degrees Celsius for two hours.Next add 150 milliliters of distilled water to a one liter round bottom flask and transfer the digested biomass sample to the flask.Wash the vial with 195 milliliters of water and transfer the water to the flask containing the digested biomass.Reflux the solution for four hours.Then cool the round bottom flask to room temperature.After 12 hours filter the solution using a G2 crucible to obtain the insoluble lignin and ash.Wash the insoluble solid with 150 milliliters of hot water to make it acid free.Dry the lignin and ash in the oven at 60 degrees Celsius for 16 hours, then transfer the solid to a Petri dish and further dry in the oven at 105 degrees Celsius for one hour.After drying place the sample in a desiccator to cool.Then weigh the cooled sample.Now perform the ash correction by heating the sample at 650 degrees Celsius for five hours in the presence of air.Determine the ash correction using the appropriate formula.Add two grams of oven dried jute biomass to a high pressure and high temperature batch reactor such as a 160 milliliter par reactor.Add 60 milliliters of water and 24 grams of acidic ionic liquid.Then close the reactor and increase the temperature to 160 degrees Celsius.Set the stirring speed to 200 RPM while the reactor is heating up to 160 degrees Celsius.Once the desired temperature is reached, increase the stirring speed to 600 RPM.After one hour, decrease the stirring speed to 200 RPM and stop the heating.Once the reactor is cool to room temperature stop the stirring and open the reactor.Separate the solid from the reaction mixture then analyze the reaction mixture using HPLC.Comparison of the catalytic activity of mineral acids and acidic ionic liquid for the conversion of jute biomass into C5 sugar is shown here.The catalytic activity is further compared with an ionic liquid without any Br
Tags
Pentosan Analysis
Jute Biomass
Sugar Monomers
Acidic Ionic Liquid
C5 Sugars
Determination Of Pentosan Concentrations
Low Biomass
Acerous Media
Catalytic Amount
Mineral Acids
1,3-propane Sultone
1-methylimidazole
Toluene
Solid Zwitterion
Vacuum Filtration
Drying Temperature
