Customized catalytic hydropyrolysis of biomass to high-quality bio-oil suitable for co-processing in FCC refining unit

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Entrained Flow Gasification of Polypropylene Pyrolysis Oil

Petrochemical products could be produced from circular feedstock, such as waste plastics. Most plants that utilize syngas in their production are today equipped with entrained flow gasifiers, as this type of gasifier generates the highest syngas quality. However, feeding of circular feedstocks to an entrained flow gasifier can be problematic. Therefore, in this work, a two-step process was studied, in which polypropylene was pre-treated by pyrolysis to produce a liquid intermediate that was easily fed to the gasifier. The products from both pyrolysis and gasification were thoroughly characterized. Moreover, the product yields from the individual steps, as well as from the entire process chain, are reported. It was estimated that the yields of CO and H(2) from the two-step process were at least 0.95 and 0.06 kg per kg of polypropylene, respectively, assuming that the pyrolysis liquid and wax can be combined as feedstock to an entrained flow gasifier. On an energy basis, the energy content of CO and H(2) in the produced syngas corresponded to approximately 40% of the energy content of the polypropylene raw material. This is, however, expected to be significantly improved on a larger scale where losses are proportionally smaller

Transformation of phenolic compounds of pyrolysis bio-oil to high-value chemicals by catalytic hydrotreatment / Hoda Shafaghat

Pyrolysis bio-oil is recognized as a renewable and carbon-neutral fuel which could be potential alternative for depleting fossil fuels. However, bio-oil is highly oxygenated and needs to be upgraded prior to be used as fuel/fuel additive. Catalytic hydrodeoxygenation (HDO) is an efficient technique for bio-oil upgrading. The reaction pathway for HDO of bio-oil is unknown since it is a mixture of hundreds of different compounds. The study on mechanism of transformation of these compounds could be helpful to propose an overall pathway for HDO of bio-oil. Phenols which are derived from pyrolysis of lignin fraction of biomass are considered as attractive model compounds for study of bio-oil HDO since they are highly stable in HDO reaction. Reaction pathway and product selectivity in HDO of phenols are highly affected by catalyst type and process conditions. Bifunctional catalysts consisting of metal and acid sites are usually used for transformation of bio-oil/bio-oil model compounds to valuable hydrocarbons. Metal and acid sites are generally involved in hydrogenation/hydrogenolysis and dehydration/hydrocracking/dealkylation/alkylation/isomerization reaction mechanisms, respectively. In this work, product selectivity of hydrogenation of phenol, o-cresol, m-cresol and guaiacol (the most abundant phenolics of bio-oil) was investigated over combined catalysts of Pd/C with zeolite solid acids of HZSM-5 (Si/Al of 30, 50 and 80) and HY (Si/Al of 30 and 60) in an autoclave batch reactor. Catalytic activity and product distribution were affected by density and strength of zeolite acid sites. Meanwhile, bifunctional metal/acid catalysts of 5 wt% Ni/HBeta, 5 wt% Fe/HBeta, 2.5 wt% Ni-2.5 wt% Fe/HBeta (NiFe-5/HBeta) and 5 wt% Ni-5 wt% Fe/HBeta (NiFe-10/HBeta) were used for HDO of a phenolic bio-oil simulated by mixing phenol, o-cresol and guaiacol. Cycloalkanes and aromatic hydrocarbons were the dominant hydrocarbons obtained over monometallic catalysts of Ni/HBeta and Fe/HBeta, respectively. Bimetallic catalyst of NiFe/HBeta showed enhanced HDO efficiency compared with monometallic catalysts of iv Ni/HBeta and Fe/HBeta due to the synergistic effect between the two metals. The effect of reaction temperature on HDO efficiency of NiFe-10/HBeta catalyst was investigated. Replacement of water with methanol as solvent in HDO of the simulated phenolic bio-oil over NiFe-10/HBeta remarkably reduced the selectivity towards hydrocarbons. High flammability of hydrogen gas in contact with air leads to difficult control of high pressurized hydrogen gas in large-scale systems. Meanwhile, molecular hydrogen production is a costly industrial process. Thus, hydrogenation study using hydrogen donor (H-donor) material as alternative for hydrogen gas could be useful in terms of cost and safety control. In this study, the potential of decalin and tetralin for use as hydrogen source was investigated in transfer hydrogenation of renewable lignin-derived phenolic compounds (phenol, o-cresol and guaiacol) and a simulated phenolic bio-oil over Pd/C and Pt/C catalysts. Reaction mechanisms of H-donor dehydrogenation and phenolics hydrogenation were studied. Furthermore, the influence of water content on transfer hydrogenation activity was studied by employing the water to donor ratios of 0/100, 25/75, 50/50 and 75/25 g/g. The catalysts used in this research were characterized by N2 adsorption, XRF, XRD, NH3-TPD, H2-TPD and TGA, and liquid products were analyzed using GC-MS

Aromatic hydrocarbon production by catalytic pyrolysis of palm kernel shell waste using a bifunctional Fe/HBeta catalyst:Effect of lignin-derived phenolics on zeolite deactivation

Lignin-derived phenolics are tightly bound with zeolite acid sites, and act as coke precursors. A bifunctional Fe/HBeta catalyst is efficient for upgrading of biomass materials with high lignin content.</p

Suppression of coke formation and enhancement of aromatic hydrocarbon production in catalytic fast pyrolysis of cellulose over different zeolites:Effects of pore structure and acidity

In catalytic pyrolysis of biomass feedstocks over zeolites, larger catalyst pores result in lower thermal coke. Besides, catalytic coke formation is suppressed by a small internal pore space or low density of acid sites.</p

Catalytic hydrogenation of phenol, cresol and guaiacol over physically mixed catalysts of Pd/C and zeolite solid acids

Product selectivity of catalytic hydrogenation of phenol, o-cresol, m-cresol and guaiacol over physically mixed catalysts of Pd/C and zeolite solid acids.</p

Optimal growth of Saccharomyces cerevisiae (PTCC 24860)on pretreated molasses for the ethanol production:The application of the response surface methodology

Saccharomyces cerevisiae (PTCC 24860) growth on pretreated sugar beet molasses was an optimized via statistical approach. In order to liberate all monomeric sugars, pretreated sugar beet molasses with dilute acid was obtained. The influence of process parameters such as sugar concentration, nitrogen source, pH and incubation time on the cell growth were investigated by a design expert software with the application of a central composite design (CCD) under response surface methodology (RSM). The optimal culture conditions were pH of 5.3, incubation time of 24 h and medium composition of 35 g reduced sugars, 1.5 g NH4Cl and 1 g yeast extract per liter of the media. At optimal cell growth conditions and incubation time of 12 h, the maximum ethanol production of 14.87 g/L was obtained