1. POLYESTERIFICATION OF POLYOL THROUGHPOLYESTERIFICATION OF POLYOL THROUGHPOLYESTERIFICATION OF POLYOL THROUGH
SOLVOLYTIC LIQUEFACTION OF CORN STOVER FORSOLVOLYTIC LIQUEFACTION OF CORN STOVER FORSOLVOLYTIC LIQUEFACTION OF CORN STOVER FOR
UNSATURATED POLYESTER RESIN PRODUCTIONUNSATURATED POLYESTER RESIN PRODUCTIONUNSATURATED POLYESTER RESIN PRODUCTION
Antonino, K. N., Cheng, A. D., Laurenciano, K., San Juan, E. L., Mission, E.Antonino, K. N., Cheng, A. D., Laurenciano, K., San Juan, E. L., Mission, E.Antonino, K. N., Cheng, A. D., Laurenciano, K., San Juan, E. L., Mission, E.
INTRODUCTIONINTRODUCTIONINTRODUCTION
Corn is the second most important crop in the Philippines having a production of 6.971 MMT and 7.408 MMT in 2011 and 2012, reCorn is the second most important crop in the Philippines having a production of 6.971 MMT and 7.408 MMT in 2011 and 2012, reCorn is the second most important crop in the Philippines having a production of 6.971 MMT and 7.408 MMT in 2011 and 2012, respespespectivelyctivelyctively
(PSA, 2012)(PSA, 2012)(PSA, 2012). It is harvested from the farm leaving most part of the plant, called corn stover, unused. Commonly, farmers use the method. It is harvested from the farm leaving most part of the plant, called corn stover, unused. Commonly, farmers use the method. It is harvested from the farm leaving most part of the plant, called corn stover, unused. Commonly, farmers use the method ofofof fieldfieldfield
burning to destroy corn stover after harvest, thus affecting the atmospheric air quality as well as human healthburning to destroy corn stover after harvest, thus affecting the atmospheric air quality as well as human healthburning to destroy corn stover after harvest, thus affecting the atmospheric air quality as well as human health (Satyendra et al., 2012)(Satyendra et al., 2012)(Satyendra et al., 2012)...
However, corn stover is a lignocellulosic biomass which contains 34.04% cellulose, 37.14% hemicellulose, and 16.80% lignin onHowever, corn stover is a lignocellulosic biomass which contains 34.04% cellulose, 37.14% hemicellulose, and 16.80% lignin onHowever, corn stover is a lignocellulosic biomass which contains 34.04% cellulose, 37.14% hemicellulose, and 16.80% lignin on aaa dry basisdry basisdry basis
(FTUD Report No. 023(FTUD Report No. 023(FTUD Report No. 023---14)14)14) and these components can be converted to a valuable material such as unsaturated polyester resin (UPR). UPR isand these components can be converted to a valuable material such as unsaturated polyester resin (UPR). UPR isand these components can be converted to a valuable material such as unsaturated polyester resin (UPR). UPR is
widely used for the manufacture of clear casting resins, coatings, buttons, polyester concrete, cladding panels, pipes, tankwidely used for the manufacture of clear casting resins, coatings, buttons, polyester concrete, cladding panels, pipes, tankwidely used for the manufacture of clear casting resins, coatings, buttons, polyester concrete, cladding panels, pipes, tanks,s,s, gratings, highgratings, highgratings, high
performance components for the marine and automotive industry, and others. Nowadays, UPRs are derived from coal and petroleumperformance components for the marine and automotive industry, and others. Nowadays, UPRs are derived from coal and petroleumperformance components for the marine and automotive industry, and others. Nowadays, UPRs are derived from coal and petroleum bababases, butses, butses, but
in this study, corn stover was utilized to produce UPR that conforms to the properties of the commerciallyin this study, corn stover was utilized to produce UPR that conforms to the properties of the commerciallyin this study, corn stover was utilized to produce UPR that conforms to the properties of the commercially---available ones.available ones.available ones.
RESEARCH METHODOLOGYRESEARCH METHODOLOGYRESEARCH METHODOLOGY
1. Preparation and Conditioning of Corn Stover1. Preparation and Conditioning of Corn Stover1. Preparation and Conditioning of Corn Stover
The preThe preThe pre---treatment of corn leaves and stalks was done separatelytreatment of corn leaves and stalks was done separatelytreatment of corn leaves and stalks was done separately
and it consisted of washing, drying, and size reduction.and it consisted of washing, drying, and size reduction.and it consisted of washing, drying, and size reduction.
2. Liquefaction of Pre2. Liquefaction of Pre2. Liquefaction of Pre---treated Corn Stovertreated Corn Stovertreated Corn Stover
Liquefaction, also known as solvolytic reaction, liquefies theLiquefaction, also known as solvolytic reaction, liquefies theLiquefaction, also known as solvolytic reaction, liquefies the
lignocellulosic content of the biomass such as cellulose, hemicellulose,lignocellulosic content of the biomass such as cellulose, hemicellulose,lignocellulosic content of the biomass such as cellulose, hemicellulose,
and lignin under acidic conditions with liquefying reagents such asand lignin under acidic conditions with liquefying reagents such asand lignin under acidic conditions with liquefying reagents such as
ethylene glycol. As a result, hydroxyl groups are introduced, thus,ethylene glycol. As a result, hydroxyl groups are introduced, thus,ethylene glycol. As a result, hydroxyl groups are introduced, thus,
producing the polyol product.producing the polyol product.producing the polyol product.
The mixture of preThe mixture of preThe mixture of pre---treated corn stover, ethylene glycol and sulfurictreated corn stover, ethylene glycol and sulfurictreated corn stover, ethylene glycol and sulfuric
acid was reacted at 160°C for 60 minutes under atmospheric pressureacid was reacted at 160°C for 60 minutes under atmospheric pressureacid was reacted at 160°C for 60 minutes under atmospheric pressure
(Liang et al., 2006)(Liang et al., 2006)(Liang et al., 2006) and was immediately quenched. Then, the polyoland was immediately quenched. Then, the polyoland was immediately quenched. Then, the polyol
produced was separated from the residue through filtration.produced was separated from the residue through filtration.produced was separated from the residue through filtration.
3. Polyesterification of Polyol3. Polyesterification of Polyol3. Polyesterification of Polyol
Polyesterification occurs by the reaction of a hydroxyl endPolyesterification occurs by the reaction of a hydroxyl endPolyesterification occurs by the reaction of a hydroxyl end---groupgroupgroup
with a carboxylic acid endwith a carboxylic acid endwith a carboxylic acid end---group to form a polyester. Water isgroup to form a polyester. Water isgroup to form a polyester. Water is
produced as the byproduced as the byproduced as the by---product of the reaction and is removed toproduct of the reaction and is removed toproduct of the reaction and is removed to
complete the reaction.complete the reaction.complete the reaction.
Polyol and phthalic acid were reacted at atmospheric pressure forPolyol and phthalic acid were reacted at atmospheric pressure forPolyol and phthalic acid were reacted at atmospheric pressure for
about 160 to 180 minutes under 160 to 220ºCabout 160 to 180 minutes under 160 to 220ºCabout 160 to 180 minutes under 160 to 220ºC (Simpson et al, 2010)(Simpson et al, 2010)(Simpson et al, 2010)...
4. Cross4. Cross4. Cross---linking of Unsaturated Polyester Resinlinking of Unsaturated Polyester Resinlinking of Unsaturated Polyester Resin
The double bond of UPR reacts with the styrene monomer,The double bond of UPR reacts with the styrene monomer,The double bond of UPR reacts with the styrene monomer,
resulting in a crossresulting in a crossresulting in a cross---linked structure which is a thermosetting resin.linked structure which is a thermosetting resin.linked structure which is a thermosetting resin.
The crossThe crossThe cross---linking was initiated through an exothermic reactionlinking was initiated through an exothermic reactionlinking was initiated through an exothermic reaction
involving methyl ethyl ketone peroxide (MEKP).involving methyl ethyl ketone peroxide (MEKP).involving methyl ethyl ketone peroxide (MEKP).
UPR was crossUPR was crossUPR was cross---linked with styrene monomer and MEKP as thelinked with styrene monomer and MEKP as thelinked with styrene monomer and MEKP as the
initiator for 3 minutesinitiator for 3 minutesinitiator for 3 minutes (Osman E. A. et. al., 2012)(Osman E. A. et. al., 2012)(Osman E. A. et. al., 2012)...
RESULTS AND DISCUSSIONRESULTS AND DISCUSSIONRESULTS AND DISCUSSION
1.1.1. Liquefaction of PreLiquefaction of PreLiquefaction of Pre---treated Corn Stovertreated Corn Stovertreated Corn Stover
The results showed that an average percent conversion ofThe results showed that an average percent conversion ofThe results showed that an average percent conversion of
52.32% was obtained through liquefying the cellulose,52.32% was obtained through liquefying the cellulose,52.32% was obtained through liquefying the cellulose,
hemicellulose, and lignin content of the prehemicellulose, and lignin content of the prehemicellulose, and lignin content of the pre---treated corn stover totreated corn stover totreated corn stover to
produce polyol.produce polyol.produce polyol.
Figure 5. Comparison between the FTIR SpectraFigure 5. Comparison between the FTIR SpectraFigure 5. Comparison between the FTIR Spectra
of Extracted Polyol and Standard Polyolof Extracted Polyol and Standard Polyolof Extracted Polyol and Standard Polyol
Based on the experiment, the extracted polyol’s FTIR spectraBased on the experiment, the extracted polyol’s FTIR spectraBased on the experiment, the extracted polyol’s FTIR spectra
were validated with the standard spectra of polyol as shown inwere validated with the standard spectra of polyol as shown inwere validated with the standard spectra of polyol as shown in
Figure 5.Figure 5.Figure 5.
2. Polyesterification of Polyol2. Polyesterification of Polyol2. Polyesterification of Polyol
Trial 3 showed the optimum variation of parameters (190ºC and 170Trial 3 showed the optimum variation of parameters (190ºC and 170Trial 3 showed the optimum variation of parameters (190ºC and 170
minutes) since further increasing the temperature and time had minimalminutes) since further increasing the temperature and time had minimalminutes) since further increasing the temperature and time had minimal
changes in the percent yield.changes in the percent yield.changes in the percent yield.
3. Cross3. Cross3. Cross---linking of Unsaturat-linking of Unsaturat-linking of Unsaturat-
ed Polyester Resined Polyester Resined Polyester Resin
The UPR that was mixed withThe UPR that was mixed withThe UPR that was mixed with
styrene monomer and MEKP gavestyrene monomer and MEKP gavestyrene monomer and MEKP gave
a total yield of 92.22%.a total yield of 92.22%.a total yield of 92.22%.
4. Testing of Unsaturated Polyester Resin4. Testing of Unsaturated Polyester Resin4. Testing of Unsaturated Polyester Resin
Figure 6. FTIR Spectra of Standard and Extracted UPRFigure 6. FTIR Spectra of Standard and Extracted UPRFigure 6. FTIR Spectra of Standard and Extracted UPR
Source: FTIR Testing, Adamson University, 2014Source: FTIR Testing, Adamson University, 2014Source: FTIR Testing, Adamson University, 2014
The experiment showed that the produced UPR’s spectraThe experiment showed that the produced UPR’s spectraThe experiment showed that the produced UPR’s spectra
conformed to the standard spectra of the commerciallyconformed to the standard spectra of the commerciallyconformed to the standard spectra of the commercially---available UPRavailable UPRavailable UPR
as presented in Figure 6.as presented in Figure 6.as presented in Figure 6.
CONCLUSIONS AND RECOMMENDATIONSCONCLUSIONS AND RECOMMENDATIONSCONCLUSIONS AND RECOMMENDATIONS
This study confirmed that corn stover, which is a lignocellulosic biomass rich in cellulose, hemicellulose, and lignin, is aThis study confirmed that corn stover, which is a lignocellulosic biomass rich in cellulose, hemicellulose, and lignin, is aThis study confirmed that corn stover, which is a lignocellulosic biomass rich in cellulose, hemicellulose, and lignin, is a potpotpotential raw materialential raw materialential raw material
for the production of unsaturated polyester resin. Moreover, the conversion of the lignocellulosic components of corn stoverfor the production of unsaturated polyester resin. Moreover, the conversion of the lignocellulosic components of corn stoverfor the production of unsaturated polyester resin. Moreover, the conversion of the lignocellulosic components of corn stover tototo polyol usingpolyol usingpolyol using
liquefaction process was proven by the results of the experiment. The polyol produced successfully undergone polyesterificatiliquefaction process was proven by the results of the experiment. The polyol produced successfully undergone polyesterificatiliquefaction process was proven by the results of the experiment. The polyol produced successfully undergone polyesterificationonon andandand
crosscrosscross---linking processes; the result of which was confirmed by the FTIR analysis of the unsaturated polyester resin formed.linking processes; the result of which was confirmed by the FTIR analysis of the unsaturated polyester resin formed.linking processes; the result of which was confirmed by the FTIR analysis of the unsaturated polyester resin formed.
On the other hand, it is recommended to use other indigenous lignocellulosic materials for the production of unsaturated polyOn the other hand, it is recommended to use other indigenous lignocellulosic materials for the production of unsaturated polyOn the other hand, it is recommended to use other indigenous lignocellulosic materials for the production of unsaturated polyestestester resin ander resin ander resin and
to consider other essential parameters and operating conditions that may influence the conversion and production processes.to consider other essential parameters and operating conditions that may influence the conversion and production processes.to consider other essential parameters and operating conditions that may influence the conversion and production processes.
Storage TanksStorage TanksStorage Tanks PipesPipesPipes
The experimental procedure was divided into two major parts: [1] preparation and conditioning of corn stover (washing, dryingThe experimental procedure was divided into two major parts: [1] preparation and conditioning of corn stover (washing, dryingThe experimental procedure was divided into two major parts: [1] preparation and conditioning of corn stover (washing, drying, a, a, and sizend sizend size
reduction) and [2] conversion processes (liquefaction, polyesterification, and crossreduction) and [2] conversion processes (liquefaction, polyesterification, and crossreduction) and [2] conversion processes (liquefaction, polyesterification, and cross---linking) as shown in the process flow diagrlinking) as shown in the process flow diagrlinking) as shown in the process flow diagram below.am below.am below.
Figure 2. Liquefaction ReactionFigure 2. Liquefaction ReactionFigure 2. Liquefaction Reaction
Source: Yamada and Ono (1990), Liu et al. (2005)Source: Yamada and Ono (1990), Liu et al. (2005)Source: Yamada and Ono (1990), Liu et al. (2005)
Body FillersBody FillersBody Fillers Gel CoatsGel CoatsGel Coats
Figure 1. Process Flow Diagram of Unsaturated Polyester Resin ProductionFigure 1. Process Flow Diagram of Unsaturated Polyester Resin ProductionFigure 1. Process Flow Diagram of Unsaturated Polyester Resin Production
Polyester ConcretePolyester ConcretePolyester ConcreteClear Casting ResinClear Casting ResinClear Casting Resin
Figure 4. CrossFigure 4. CrossFigure 4. Cross---linking Reactionlinking Reactionlinking Reaction
Source: Dodiuk, H. and Goodman, S. (2014)Source: Dodiuk, H. and Goodman, S. (2014)Source: Dodiuk, H. and Goodman, S. (2014)
Figure 3. Polyesterification ReactionFigure 3. Polyesterification ReactionFigure 3. Polyesterification Reaction
Source: Dodiuk, H. and Goodman, S. (2014)Source: Dodiuk, H. and Goodman, S. (2014)Source: Dodiuk, H. and Goodman, S. (2014)
Peak values:
Extracted = 3300.29 cm-1
Standard = 3300-3385 cm-1
Peak values:
Extracted = 1034.79 cm-1
Standard = 1000-1090 cm-1
Peak values:
Extracted = 1719.53 cm-1
Standard = 1700-1727 cm-1