-To design the reactor for the catalytic
conversion of crude glycerol (a by-product of Bio-diesel production) into
-To identify a suitable catalyst for the efficient conversion of crude
glycerol to methanol
-To increase the selectivity of methanol and catalyst recycle using
zeolite coated fluorine doped tin oxide and process optimization using a batch
While the production of Bio-diesel (from transesterification of
triglycerides with methanol) is
increased, significant amounts of glycerol,
a by-product that will become abundant is produced if a large scale production
of Bio-diesel is implemented. The glycerol by-product amount to about 10wt% of total Bio-diesel produced
(one tenth of the mass of bio-diesel). Rather than considering the crude
glycerol by-product as a waste researches have been made to convert the waste
glycerol into value added products. Often, several reactions of glycerol using
acid catalysts involve the dehydration reaction that leads to the production of
acrolein (2-Propenal). Currently,
fossils fuels are the major sources of methanol. Glycerol will serve as a
potential and greener alternative source for methanol. Previously established
technologies provide a complex pathway for methanol production from glycerol by
gasification to syngas mixture and further conversion using fischer-tropsch
process or catalysts to yield methanol. The complexity and cost efficiency of
such methodologies demanded the need for a much simpler mechanism for methanol
production. Studies made on glycerol to
methanol conversion clearly showed that basic
oxides when used as catalysts enhanced the production of methanol at
higher temperatures. Yet the conversion of glycerol and selectivity of methanol
remain at very low range. Hence we are aiming at increasing the conversion and selectivity of the
respective compounds using different catalysts such as copper loaded zeolite (HSZM-5), zirconium-copper loaded zeolite (HSZM-5),
zirconium loaded zeolite (HSZM-5) and
zeolite (HSZM-5) coated fluorine doped
tin oxide which have never been used before for the direct conversion of
glycerol to methanol in a newly designed stainless steel reactor of volume one litre.
3. LITERATURE SURVEY
Samad et. al (2016),
used fluorine doped tin oxide catalyst in
supercritical fluid state to convert glycerol to methanol. He proposed that
fluorine doped tin oxide is the novel heterogeneous catalyst for glycerol conversion to methanol in sub
critical water reaction. The sub critical water reaction was conducted under
optimal and mild conditions at a reaction temperature of 300 °C. The reaction time of 30 min, and the low temperature is sufficient to maintain the
liquid phase. Initial feedstock (glycerol) concentration and catalyst amount of
20wt% and 0.01 g respectively, were utilized and
glycerol conversion and methanol selectivity were measured using gas
chromatography flame ion detector (GC-FID)
analysis. Optimum glycerol conversion of ~80% was achieved, with methanol as the major product with
selectivity of ~100%. The
subcritical water method can also be applied for extraction process as well as
biomass conversion by optimizing some parameters such as reaction time, Catalyst
amount, reaction temperatures, and catalyst cyclablity.
HAIDER, et . al
(2015), said that
crude glycerol can be reacted with water over a very simple basic oxide or redox oxide catalysts
to produce methanol in high yields, together with other useful chemicals, in a
one-step low pressure process.
They used basic catalysts like MgO, CaO
for the conversion of glycerol into methanol while the hydrogen source for the above conversion is water which acts as both solvent and reactant during the
process. They observed that when calcium
oxide is used as catalyst for the conversion reaction the majority of
the product formed was acrolein. But when the Magnesium oxide is used as the catalyst majority of the products
formed were methanol at 300°C.
The selectivity of methanol and conversion of this process were
observed to be 30% and 25% respectively.
MOHAMMED, et . al
that their preliminary work was studying the effect of zeolite (HSZM-5), with different amounts of metals copper and nickel being loaded
on it, on the conversion and selectivity of glycerol and methanol respectively.
Their experiments were carried out in the presence of nitrogen gas (inert
carrier) in a fixed bed reactor at 500°C
and atmospheric pressure. The
catalysts used, were characterized by XRD
while the products were analyzed using GC-FID.
Conversion and yield of methanol were
calculated for different sample mixes. The results from their experiments showed
that the Cu/HSZM-5 had the
highest conversion and methanol yield 100%
and 6.5% respectively. They also
concluded that the presence of nickel will reduce the conversion of methanol.
4. PROPOSED WORK WITH METHODOLOGY
Crude glycerol obtained from
bio-diesel production should be dehydrated using a basic catalyst at a
relatively higher temperature than acid based catalytic dehydration to produce
reasonable fractions of methanol.
1: CRUDE GLYCEROL CHARACTERISATION
total and free glycerol content in the available crude glycerol samples is to
be estimated by performing spectroscopic analyses such as NMR and FTIR
spectroscopies. NMR spectroscopic method will determine the compounds and
impurities present in glycerol. Crude glycerol will contain two distinct
layers, a predominant glycerol layer and a layer which contains most of the
organic compounds and impurities present in crude glycerol. Such layers can be
easily separated by using simple phase separation techniques.
2: CATALYST SELECTION
next step is to find out a catalyst or catalyst mix which best achieves the
desired methanol selectivity (> 90%).we
are planning to test two mixtures of catalysts 1) different mixtures of HSZM-5
zeolite catalyst loaded with
Cu/Zr with varying wt% of Cu and Zr.2) fluorine doped tin oxide mixed with metal loaded HSZM-5
catalyst. Both the catalyst mixes are subjected to TGA and TPD analysis to
identify their desorption behavior at different temperatures. Since methanol
conversion is a high temperature process, the catalyst must show lower
desorption at higher temperature ranges. The surface topography of the catalyst
will be studied using SEM. The catalyst mixes with the desired properties are
tested by reacting with stoichiometric amounts of crude glycerol as well as
pure glycerol on a laboratory scale.
3: REACTOR DESIGN
are planning to design the model reactor as a stainless steel jacketed batch
reactor with an estimated volumetric capacity of 1 litter. The reactor will be
designed using CAD. Glycerol has a boiling point of 290 0C. The
dehydration reaction will be carried out around 300 °C. Hence we
will be performing vapor phase dehydration. Therefore an impeller or agitator
may not be required. All the reactor components will be made of stainless steel
to withstand the reaction temperature and prevent corrosion.
HIGH PRESSURE DOUBLE JACKETED STAINLESS STEEL
A jacketed stainless steel
A heating coil at the bottom
An outer cooling jacket
A stainless steel seal at
Inlet and outlet valves
4: PROCESS OPTIMIZATION
ratios of the reactants and catalysts are tested in the reactor at different
reaction conditions and the yield and selectivity of methanol produced for each
batch is calculated. The selectivity will indicate the purity of the obtained
methanol product.in general, glycerol dehydration to methanol is a high
temperature process. Hence we will try to identify a temperature range that
will provide the desired yield and selectivity and also will not affect or
damage the activity of the catalyst. The optimum residence time will also be
calculated and the effect of the residence time on methanol quality will be
interpreted. The catalyst must provide better yield at shorter residence time
considering that the reaction is highly exothermic.
5: PRODUCT ANALYSIS
methanol obtained requires purification since it may contains possible
impurities such as unreacted glycerol, catalyst particles, acrolein and other
alcohols and aldehydes. They must be removed as they will affect the purity and
viability of methanol to be used as a platform chemical. NMR spectroscopic
studies will be performed to identify the impurities. We are also interested in
upgrading the following properties of methanol to standard values
Flash and fire point
Particulate matter (PM)
proposed work will be implemented in the following steps:
glycerol collection, characterization and purification
streaming process for product recovery
purification and characterization
Crude glycerol from bio-diesel production process
will be collected. Compositional studies on the samples will be performed as
mentioned above using spectroscopic methods. The impurities present in the
crude glycerol sample will be identified and their adverse effects on the
dehydration reaction or the catalyst structure and activity will be studied.
Such impurities will be removed using simple phase separation techniques as
most of them will be accumulated in a distinct aqueous layer. Ash, if present and
other solid particles will be removed using activated carbon.
mentioned earlier, we are interested in using metal loaded HSZM-5 zeolite
catalyst and a mix of the same with fluorine doped tin oxide. The selection of
an efficient catalyst mix ratio is essential as it will directly affect the
feasibility of the process since dehydration is a highly exothermic reaction.
Hence the stability of the catalyst at elevated temperatures will be studied.
The procedure will be repeated for different mixtures of the catalyst with
varying wt%. Compositional analysis will also be performed for each catalysts
sample. The catalyst will then be tested with the feed mixtures (both crude
glycerol and pure glycerol) on an experimental scale.
are planning to design a batch reactor of volumetric capacity (1 liter). The
reactor dimensions will be calculated. The reactor will be constructed using
stainless steel with a heating coil (either spiral wound or bottom fixed) to
provide the reaction temperature. The reactor will have a stainless steel seal
at the top. It will be provided with a cooling jacket since the reaction is
exothermic and carried out at higher temperatures. A pressure gauge and a
thermocouple will also be installed to monitor the reaction parameters. An
inlet at the top will be provided to introduce the feed mixture and also an
outlet valve at the bottom to collect the product.
amounts of crude glycerol and catalyst to be fed to the reactor will be
predetermined. Variable ratios of the reaction mixture will be introduced into
the reactor and their respective yield and selectivity will be calculated.
Dehydration will take place at atmospheric pressure. We are planning to achieve
a selectivity > 90% within a temperature range of 3000C – 4000C.
Hence the catalyst mix which will provide the required parameters will be
identified by comparing the obtained results and varying
the catalyst properties accordingly. A comparative study on the effect of
copper and zirconium on HSZM-5 will also be performed.
produced from the reactor will also be subjected to compositional analysis by
spectroscopic methods as mentioned earlier. Methanol will have considerable wt
% of water which will cause corrosion and limit the use of methanol as a fuel
or fuel additive. Hence water if present will be removed. We will also try to
upgrade the following properties of methanol to improve it’s quality:
and fire point
matter (PM) content
Month 1 Month 2 Month 3 Month 4 Month 5 Month 6
Glycerol analysis —
Reactor design ————————-
Process optimization ————————————–
Product testing ————————————————————
Completion of project ————————————————————————-
-Collection of crude
glycerol formed from the bio diesel production
– Characterization of the collected
crude glycerol and testing for impurities
– Removal of impurities found in the
crude glycerol using suitable techniques
-Preparation of catalysts
for glycerol conversion
– Analyzing the properties of the
-Testing and selection of suitable
– Studying different
reaction kinetics necessary for designing reactor
– Design and construction of the reactor
– Testing sample with
catalyst mixtures in batch reactor
– Optimization of process
– Testing the purity of methanol
formed in the reaction
– Purification and upgradation of
methanol to meet its specifications
– Determining the
selectivity of methanol and conversion of methanol also limitations and
difficulties during the project
– Completion of the project and
submission to CTDT
6. EXPECTED OUTCOME/RESULTS
The crude glycerol is
expected to contain the unreacted organic matter, metal and non-metal of the
catalysts, and water. Of which, those would affect our process are likely to be
removed as much as possible.
CATALYST SELECTION AND PREPARATION
The stability of the
catalysts is essential for the reaction to take place. Since the conversion
reaction occurs around 300°C, the catalysts which would withhold those
standards are expected to select for preparation. Also it is expected that such
stable catalysts will ensure the selectivity of the product and conversion of
the reactant to the maximum extent.
In reactors usually
the failures may occur due to improper design equations, scale formations and
corrosion formation. Hence it is expected to design the reactor in such a way
that it follows proper reaction kinetics and compatible to the reaction
mixtures at operating conditions. It is also expected that the reactor is sufficiently
corrosion resistance with its stainless steel sealing.
Using copper loaded
zeolite (HSZM-5) as catalyst the selectivity is expected to be around 90%,
since copper would be able to penetrate the zeolite molecule more readily
because of the possibility to stabilize the cu o interactions that do not alter
the charge of host frame network. And this is expected to greatly effecting on
the methanol production.
The same zeolite when
loaded with zirconium which also has similar reaction properties as copper is
expected to give higher or lesser selectivity than cu/HSZM-5. Also when the
same mixtures with only difference of having fluorine doped tin oxide the
reaction is expected to give both selectivity and conversion around 90%.This is
because of the good catalytic activity of the fluorine doped tin oxide over
metal loaded zeolite.
METHANOL QUALITY IMPROVEMENT
Methanol usually has the
viscosity of about 0.554 mpa s at 0°C. The methanol formed from the glycerol is
expected to have viscosity higher than the normal pure methanol, due to the
composition of inseparable unreacted organic components. This increased
viscosity is expected to be reducible with suitable additives.
2. Specific gravity
The specific gravity test
for methanol can be done in hydrometer method or specific gravity bottle
method. For normal methanol the specific gravity value is 0.796 at 15°C. It is
expected that specific gravity for the methanol produced from glycerol is
higher than normal methanol as its viscosity is also comparatively higher.
3. Boiling point
The boiling point of normal
methanol is about 64.6°C when the pressure is 101.3kpa. It is expected that due
to increased organic components and increased hydrocarbon content the methanol
produced from the glycerol will have a slightly higher boiling point than the
produced can be recycled to be used for the trans-esterification step of
bio-diesel production. This will increase the economy and viability of
bio-diesel production subsequently decreasing the rate of bio-diesel.
2. Methanol is used as a feedstock to produce
chemicals such as acetic acid and formaldehyde, which in turn are used in
products like adhesives, foams, plywood subfloors, solvents and windshield
3. Methanol can be used on its own as a vehicle
fuel or blended directly into gasoline to produce a high-octane, efficient fuel
with lower emissions than conventional gasoline.
4. Methanol is used to produce methyl tertiary
butyl ether (MTBE), a gasoline component that improves air quality, and
dimethyl ether (DME), a clean-burning fuel with similar properties to propane.
hydro processing of crude glycerol from bio-diesel production will be carried
out using Zirconium / Copper loaded HSZM-5 zeolite and it’s combination with
fluorine doped tin oxide will be carried out. Optimization of the process in a
pilot plant will also be performed. The methanol product will be tested and
processed to achieve its purity and optimum characteristics.
Shi, X. H., and K. J. Xu. “Properties of
fluorine-doped tin oxide films prepared by an improved sol-gel process.” Materials
Science in Semiconductor Processing 58 (2017): 1-7.
Mohamed, M., et al. “Conversion of
glycerol to methanol in the presence of zeolite based catalysts.” Clean
Energy and Technology (CET), 2011 IEEE First Conference on. IEEE, 2011.
Haider, Muhammad H., et al. “Efficient
green methanol synthesis from glycerol.” Nature chemistry 7.12
Thanh, Le Tu, et al. “Catalytic
technologies for biodiesel fuel production and utilization of glycerol: a
review.” Catalysts 2.1 (2012): 191-222.
Tianfeng, Cai, et al. “Purification of
crude glycerol from waste cooking oil based biodiesel production by orthogonal
test method.” China Petroleum Processing and Petrochemical Technology
15.1 (2013): 48-53.
Hu, Shengjun, et al. “Characterization of
crude glycerol from biodiesel plants.” Journal of agricultural and food
chemistry 60.23 (2012): 5915-5921.
Nimlos, Mark R., et al. “Mechanisms of
glycerol dehydration.” The Journal of Physical Chemistry A 110.18