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Katalysatorval och beaktanden vid flerstegsomvandling av glukos till glycerol

Nörregård, Öyvind LU (2018) KET920 20161
Chemical Engineering (M.Sc.Eng.)
Abstract
Through hydrogenation of glucose to sorbitol followed by hydrogenolysis of sorbitol to glycerol a pathway to produce bio propane from lignocellulosic material has been confirmed.
A wide range of catalyst was tested, in an autoclave batch reactor, to scout the activity of catalysts already proven active, according to previous literature, as well as catalysts not mentioned in literature for the specific reaction. Catalysts well known for both the hydrogenation of glucose and the hydrogenolysis of sorbitol are catalyst including either nickel or ruthenium as the active metal.
The most active system was found to be Ni supported on γ-Al2O3 for both the hydrogenation and the hydrogenolysis. For the unknown process step, the hydrogenolysis,... (More)
Through hydrogenation of glucose to sorbitol followed by hydrogenolysis of sorbitol to glycerol a pathway to produce bio propane from lignocellulosic material has been confirmed.
A wide range of catalyst was tested, in an autoclave batch reactor, to scout the activity of catalysts already proven active, according to previous literature, as well as catalysts not mentioned in literature for the specific reaction. Catalysts well known for both the hydrogenation of glucose and the hydrogenolysis of sorbitol are catalyst including either nickel or ruthenium as the active metal.
The most active system was found to be Ni supported on γ-Al2O3 for both the hydrogenation and the hydrogenolysis. For the unknown process step, the hydrogenolysis, the selectivity was considerably high, 44%. This was though found after almost the triple operating time compared to certain literature with still low conversion rates of 36%, which was explained by the mild conditions and the low catalyst to sorbitol ratio 0.5 wt.-%.
Other unexpected findings was the negative effect of a basic promoter for most systems and also the regenerating effect of sorbitol when adding hydrogen to the system which introduces further possibilities in research; studying tentatively the effect of hydrocracking derived from the high reactivity, specifically for the acidic catalyst, and if the retro-aldol is a crucial step, only obtained before the adding of hydrogen. (Less)
Popular Abstract
Glycerol has flooded the market for almost two decades, as the result of the large increase in the production of biodiesel, in which glycerol is a stoichiometric by-product. But with new research, a pathway to produce bio-based propane from glycerol has been developed. To keep the glycerol price low and as well to state an economically feasible process route, a pathway to produce glycerol from glucose (from lignocellulosic materials) has been proposed. By hydrogenation of glucose, obtained from processed lignocellulosic materials, sorbitol can be produced. This is done in large scale commercial processes and can be performed productively, with high selectivity towards sorbitol. Further hydrogenolysis of sorbitol has proven primarily one of... (More)
Glycerol has flooded the market for almost two decades, as the result of the large increase in the production of biodiesel, in which glycerol is a stoichiometric by-product. But with new research, a pathway to produce bio-based propane from glycerol has been developed. To keep the glycerol price low and as well to state an economically feasible process route, a pathway to produce glycerol from glucose (from lignocellulosic materials) has been proposed. By hydrogenation of glucose, obtained from processed lignocellulosic materials, sorbitol can be produced. This is done in large scale commercial processes and can be performed productively, with high selectivity towards sorbitol. Further hydrogenolysis of sorbitol has proven primarily one of the most suitable ways to end up with the requested product. The backbone carbon structure of six carbon atoms makes it easy to imagine a split between the two middle carbons resulting in two glycerol molecules. Though the fairly easy process route, large difficulties were found in acquiring an economically feasible product yield.
A wide range of catalyst was tested, in an autoclave batch reactor, to scout the activity of catalysts already proven active, according to previous literature, as well as catalysts not mentioned in literature for the specific reaction. Catalysts well known for both the hydrogenation of glucose and the hydrogenolysis of sorbitol are catalyst including either nickel or ruthenium as the active metal.
The just mentioned active metals supported on γ-Al2O3 was proven to have high conversion rates as well as high selectivity in the hydrogenation of glucose. With catalyst loadings of 0.5% in weight and active metal concentrations lower or comparable to literature, highly active hydrogenation systems were found with both types of catalysts. For the unknown system of sorbitol hydrogenolysis, the case was different. The most active system was found to be Ni supported on γ-Al2O3 for which the selectivity was considerably high, 44%. This was though found after almost the triple operating time compared to certain literature with still low conversion rates of 36%.
Unexpected results were found in the addition of basic promoter which lowered the activity for the nickel catalyst which according to literature would increase the activity of the system. The increase in activity was only found for the catalyst using ruthenium as active metal. Other remarkable findings were the high conversion of sorbitol before the system was put to operating conditions. This together with the regenerating sorbitol concentration with the adding of hydrogen to the system, leads one to think that the start-up procedure before introducing hydrogen may be a crucial step for achieving a more sought for product distribution. This introduces further possibilities in the research area, studying tentatively the effect of hydrocracking derived from the high reactivity, specifically for the acidic catalyst, and if the retro-aldol is a crucial step, only obtained before the adding of hydrogen. (Less)
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author
Nörregård, Öyvind LU
supervisor
organization
alternative title
Catalyst choice and considerations for multiple step conversion of glucose to glycerol
course
KET920 20161
year
type
H2 - Master's Degree (Two Years)
subject
keywords
Catalysis, chemical engineering, kemiteknik
language
Swedish
id
8938867
date added to LUP
2018-06-04 16:12:41
date last changed
2018-06-04 16:12:41
@misc{8938867,
  abstract     = {Through hydrogenation of glucose to sorbitol followed by hydrogenolysis of sorbitol to glycerol a pathway to produce bio propane from lignocellulosic material has been confirmed. 
A wide range of catalyst was tested, in an autoclave batch reactor, to scout the activity of catalysts already proven active, according to previous literature, as well as catalysts not mentioned in literature for the specific reaction. Catalysts well known for both the hydrogenation of glucose and the hydrogenolysis of sorbitol are catalyst including either nickel or ruthenium as the active metal.
The most active system was found to be Ni supported on γ-Al2O3 for both the hydrogenation and the hydrogenolysis. For the unknown process step, the hydrogenolysis, the selectivity was considerably high, 44%. This was though found after almost the triple operating time compared to certain literature with still low conversion rates of 36%, which was explained by the mild conditions and the low catalyst to sorbitol ratio 0.5 wt.-%.
Other unexpected findings was the negative effect of a basic promoter for most systems and also the regenerating effect of sorbitol when adding hydrogen to the system which introduces further possibilities in research; studying tentatively the effect of hydrocracking derived from the high reactivity, specifically for the acidic catalyst, and if the retro-aldol is a crucial step, only obtained before the adding of hydrogen.},
  author       = {Nörregård, Öyvind},
  keyword      = {Catalysis,chemical engineering,kemiteknik},
  language     = {swe},
  note         = {Student Paper},
  title        = {Katalysatorval och beaktanden vid flerstegsomvandling av glukos till glycerol},
  year         = {2018},
}