Hydrodeoxygenation of Aqueous Phase Catalytic Pyrolysis Oil to Liquid Hydrocarbons Using Multi-Functional Nickel Catalyst

Herein we investigated the hydrodeoxygenation (HDO) of aqueous phase pinyon-juniper catalytic pyrolysis oil (APPJCPO) using a new multifunctional red mud-supported nickel (Ni/RM) catalyst. The organic liquid yield after HDO of APPJCPO using 30 wt. % Ni/RM at reaction temperature of 350 °C was 47.8 wt. % with oxygen content of 1.14 wt. %. The organic liquid fraction consisted of aliphatics, aromatics, and alkylated aromatic hydrocarbons as well as small amounts of oxygenates. The RM support catalyzed ketonization of carboxylic acids. The Ni metal catalyzed partial reduction of oxygenates that underwent carbonyl alkylation with aldehydes and ketones on the RM. Catalyst deactivation assessment suggested that oxidation and coke formation were the main controlling factors for deactivation of Ni and RM respectively. For comparison, commercial (~65wt.%) Ni/SiO2-Al2O3 was tested in HDO experiments which gasified the soluble organics in APPJCPO and did not produce liquid hydrocarbons

Reformulated Red Mud: A Robust Catalyst for In Situ Catalytic Pyrolysis of Biomass

Biomass feedstocks contain inorganic compounds generally classified as ash. The ash consists of compounds of potassium, calcium, magnesium, silicon, phosphorus. and other elements. These elements have been reported to influence both the pyrolysis reactions as well as the destabilization of the pyrolysis oils during storage. The inorganic elements have also been reported to deposit on catalyst surfaces during in situ catalytic pyrolysis leading to the eventual deactivation of acidic catalysts such as zeolites. The deposition of inorganic elements and their effects on formulated red mud (FRM) catalyst during in situ catalytic pyrolysis of pinyon juniper wood was investigated. The inorganic elements were measured for the fresh, coked, and regenerated catalysts. The BET specific surface area of the FRM catalyst decreased from 76 m2/g for the fresh catalyst to 53 m2/g for the stable regenerated catalyst. After three regenerations, the BET specific surface area stabilized at 53 m2/g and remained constant after all other regenerations. Potassium, calcium, magnesium, and phosphorus were deposited on the catalyst. Potassium deposition was linear with the number of regenerations while magnesium and calcium depositions were initially rapid but leveled-off after three regenerations of the catalyst. Phosphorus deposition was almost linear, but the data were more scattered compared to that of potassium. The potassium deposition was attributed to physical phenomenon whereas calcium and magnesium depositions were more akin to chemical reactions related to the loss of BET surface area of the catalyst. The deposition of these elements on the surface of the catalyst did not deactivate it. After each catalyst regeneration, the oil yield was not significantly affected and the oil oxygen content and viscosity decreased slightly. This clearly showed that formulated red mud is a robust catalyst suitable for in situ catalytic fast pyrolysis of biomass

Ethanol production of semi-simultaneous saccharification and fermentation from mixture of cotton gin waste and recycled paper sludge

Ethanol production from the steam-exploded mixture of 75% cotton gin waste and 25% recycled paper sludge in various conditions was investigated by semi-simultaneous saccharification and fermentation (SSSF) consisting of a pre-hydrolysis and a simultaneous saccharification and fermentation (SSF). Four cases were studied: 24-h pre-hydrolysis + 48-h SSF (SSSF 24), 12-h pre-hydrolysis + 60-h SSF (SSSF 12), 72-h SSF, and 48-h hydrolysis + 24-h fermentation (SHF). The ethanol concentration, yield, and productivity of SSSF 24 were higher than those of the other operations. A model of SSF was used to simulate the data for four components in SSF. The analysis of the reaction rates of cellobiose, glucose, cell, and ethanol using the model and the parameters from the experiments showed that there was a transition point of the rate-controlling step at which the cell growth control in the initial 2 h was changed to the cellobiose reaction control in later period during ethanol production of SSF from the mixture

Catalytic Pyrolysis of Poly Vinyl Chloride as a Viable Way of Waste Management

The main purpose of this investigation is to achieve the dechlorination and cracking of PVC producing a low chlorinated oil using a single step process; finding and using a suitable adsorbent that captures the chlorine released in the decomposition of the Poly Vinyl Chloride in the solid phase; then use the adsorbent to enhance red mud chlorine absorption activity. Find an alternative viable use for the waste PVC and red mud that will reduce landfilling. Calcium Hydroxide was selected as the main chlorine adsorbent since it captured 75% chlorine in the solid phase. The calcium hydroxide was mixed with red mud (50/50 wt/wt), and pyrolyzed at 400 °C in a N2 environment for 60 min in a fixed bed reactor using PVC to catalyst ratio of 1:1. The oil had less than 10 ppm chlorinated products and had a higher heating value of 40.78 MJ/kg

New Rapid Method for the Determination of Total Acid Number (Tan) of Bio-Oils

Abstract Fast pyrolysis oils are one source of renewable liquid fuels, which could be used as green fuels in a sustainable manner. The ASTM D664 method used to determine the acidic constituents in petroleum products, lubricants, and biodiesel requires mixtures of isopropyl alcohol (IPA) and toluene as solvent. The ASTM method also uses large quantities of solvents for the total acid number (TAN) determination. The ASTM D664 method has been adopted for the determination of TAN for bio-oils data published in literature. However, the properties of bio-oils are different from those of petroleum products and biodiesel, because biooils are soluble in polar solvents and partially soluble in water whereas petroleum products and biodiesel are insoluble in water and are more non-polar. An alternative method which is more suitable for TAN determination of bio-oil has been developed and validated. Aqueous potassium hydroxide (0.1 M KOH) was used as standard titrant instead of 0.1M KOH in alcoholic solution, and acetone was used as titration solvent instead of mixtures of toluene and IPA as specified in the ASTM method. Four bio-oil samples were analyzed for their TAN using the new method and the ASTM method for comparison. The results showed that TAN of bio-oil samples determined by the new method were in good agreement with those determined by the ASTM method. It was confirmed that the new method was simpler and relatively cheaper and more suitable for TAN determination of the pyrolysis oils than the ASTM D664 method

Hydraulic retention time effects on wastewater nutrient removal and bioproduct production via rotating algal biofilm reactor

open4siThe authors would like to acknowledge the Sustainable Waste to Bioproducts Engineering Center (SWBEC) at Biological Engineering Department in Utah State University (USU – United States) and University of Bologna – Italy for technical and financial supports and professional research facilities. Also special thanks to the SWBEC team for help and assistance in the Bioenergy and Biomanufacturing laboratoryRotating algal biofilm reactor (RABR) technology was successfully employed in an effective strategy to couple the removal of wastewater nutrients with accumulation of valuable bioproducts by grown algae. A secondary stage municipal wastewater was fed to the developed system and the effects of the hydraulic retention time (HRT) parameter on both nutrient removal and bioproduct production were evaluated under fed-batch operation mode. Two sets of bench scale RABRs were designed and operated with HRTs of 2 and 6 days in order to provide competitive environment for algal growth. The HRT significantly affected nitrogen and phosphorus uptakes along with lipid and starch accumulations by microalgae in harvested biofilms. Domination of nitrogen removal in 2-day HRT with higher lipid accumulation (20% on dried weight basis) and phosphorus removal in 6-day HRT with higher starch production (27% on dried weight basis) was observed by comparing the performances of the RABRs in duplicate runs.openIman Shayan, Sahand; Agblevor, Foster A.; Bertin, Lorenzo; Sims, Ronald C.Iman Shayan, Sahand; Agblevor, Foster A.; Bertin, Lorenzo; Sims, Ronald C

Microbubble assisted polyhydroxybutyrate production in Escherichia coli

Background One of the potential limitations of large scale aerobic Escherichia coli fermentation is the need for increased dissolved oxygen for culture growth and bioproduct generation. As culture density increases the poor solubility of oxygen in water becomes one of the limiting factors for cell growth and product formation. A potential solution is to use a microbubble dispersion (MBD) generating device to reduce the diameter and increase the surface area of sparged bubbles in the fermentor. In this study, a recombinantE. coli strain was used to produce polyhydroxybutyrate (PHB) under conventional and MBD aerobic fermentation conditions. Results In conventional fermentation operating at 350 rpm and 0.8 vvm air flow rate, an OD600 of 6.21 and PHB yield of 23 % (dry cell basis) was achieved. MBD fermentation with similar bioreactor operating parameters produced an OD600 of 8.17 and PHB yield of 43 % PHB, which was nearly double that of the conventional fermentation. Conclusions This study demonstrated that using a MBD generator can increase oxygen mass transfer into the aqueous phase, increasing E. coli growth and bioproduct generation