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Little is known about the effect of biochar created from poultry litter on soil properties and plant growth. Five studies were conducted using biochar made by the fast pyrolysis of poultry litter. Two were greenhouse studies and three were field studies. The greenhouse studies were conducted with a sandy loam soil and a silt loam soil. First, lettuce (Lactuca sativa L) seeds were germinated in the greenhouse across biochar incorporation rates from 0 to 100%, and secondly a trial was conducted in which green peppers (capsicum annum L) were grown in soils with up to 5% biochar by weight. Elemental analysis was completed on the biochar and the soils were analyzed for bulk density (BD), water holding capacity (WHC), pH, cation exchange capacity (CEC), soluble salts (SS) and extractable nutrients. The field studies all used the rates of 0, 4.5, and 9 Mg ha-1 biochar and the rates were applied in the early spring of 2009 and 2010. Biochar was surface applied on a tall fescue pasture [Lolium arundinaceum (Schreb.) Darbysh. (=Festuca arundinacea Schreb. subsp. arundinacea)] and tilled in on two green pepper field sites. The soils were analyzed for carbon (C) content, pH, CEC, Mehlich 1 P, and SS. No significant difference was found in yields at any of the three sites, but differences in forage quality were found. Biochar made from poultry litter showed several benefits as a soil amendment in all the studies, but application rates would be limited by soil test P and pH. / Master of Science

Si nanoparticles are new prospective optoelectronic materials. Unlike bulk Si cry-stals, Si nanoparticles display intriguing room-temperature photoluminescence. A major challenge in the fabrication of Si nanoparticles is the control of their size distribution. The rare-earth element Er has unique photo emission properties, including low pumping power, and a temperature independent, sharp spectrum. The emission wavelength matches the transmission window of optical fibers used in the telecommunications industry. Therefore, the study of Er-doped Si nanoparticles may have practical significance. The goals of the research described in this dissertation are to investigate vapor phase pyrolysis methods and to characterize the microstructure and associated defects, particles size distributions and photoluminescence efficiencies of doped and undoped Si nanoparticles using analytical transmission electron microscopy, high resolution electron microscopy, and optical spectroscopy. Er-doped and undoped Si nanoparticles were synthesized via vapor-phase pyrolysis of disilane at Texas Christian University. To achieve monodisperse size distributions, a process with fast nucleation and slow growth was employed. Disilane was diluted to 0.48% with helium. A horizontal pyrolysis oven was maintained at a temperature of 1000 °C. The oven length was varied from 1.5 cm to 6.0 cm to investigate the influence of oven length on the properties of the nanoparticles. The Si nanoparticles were collected in ethylene-glycol. The doped and undoped Si nanoparticles have a Si diamond cubic crystal structure. Neither Er precipitation, Er oxides or Er silicides were detected in any of the samples. The Er dopant concentration was about 2 atom% for doped samples from the 3.0 and 6.0 cm ovens as determined by quantitative analysis using X-ray energy dispersive spectroscopy. The average Si nanoparticle size increases from 11.3 to 15.2 nm in the doped samples and from 11.1 to 15.7 nm in the undoped samples as the oven length increases from 1.5 to 6.0 cm. HREM data show that average Si nanocrystallite size varies from 6.4 to 3.3 to 5.9 nm in the doped samples, and from 7.5 to 12.2 nm in the undoped samples as the oven length increases. Room-temperature Er photoluminescence has been detected near 1.54 :m from all doped samples. Saturation of the Er photoluminescence intensity at large emission power and the monotonic decrease of the intensity as a function of the emission wavelength in the doped sample from the 3.0 cm oven suggest that a carrier-mediated energy transfer process occurs in the Er-doped Si nanoparticles. It is the first time to successfully fabricate and investigate Er-doped Si nanoparticles.

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To assess the performance and future possibilities of catalytic microwave pyrolysis, laboratory-scale experiments were conducted on a widely available biomass feedstock, Eucalyptus grandis. Non-catalysed microwave pyrolysis was conducted under varying conditions to determine important factors of the microwave pyrolysis process and to conduct a basic performance evaluation. Future possibilities of microwave pyrolysis were determined by comparison to available technologies. Calcined Mg-Al LDH clay (layered double oxide or LDO) was used as catalyst to improve the quality of the pyrolysis process and its products. The heating and reaction mechanisms for microwave pyrolysis show that it offers distinct advantages over conventional pyrolysis. The main advantages are rapid and efficient volumetric heating, as well as acceptable yields at lower temperatures (much lower than those required by conventional pyrolysis), which can possibly lead to significant energy savings. Comparing the performance of a modified domestic microwave to an off-the-shelf microwave unit (Roto Synth) proved that cheap and comparative microwave research is possible. The yields from the domestic microwave products compared very closely to those of the Roto Synth unit, each having yields for char, oil and gas of 47.9%, 33.2%, 18.9% and of 46.8%, 32.7%, 20.55% respectively. The cost of the modified domestic setup was ~1% of that of the off-the-shelf unit. The use of a quartz reactor and slight adjustments to the stepper motor driver and thermocouple are recommended for future use. The pyrolysis process was found to be very dependent on power and power density. Higher powers increase the liquid and gas yields and a critical power density was identified between 800W and 1000W. The effects of power density were interesting and led to conclusions regarding the penetration depth of microwaves which could possibly play a significant role in the scale-up of microwave pyrolysis technology. Microwave pyrolysis undeniably has several advantages over conventional pyrolysis. However, for it to become competitive, microwave fast pyrolysis technologies need to be developed through the use of mixed bed reactors that can achieve fast heating rates. Possible candidates include rotating cone and fluidised bed reactors. Hybrid technology also provides unique advantages and has huge potential. Comparison of pyrolysis technologies is difficult without good data on continuous microwave pyrolysis reactors, and therefore the development of such reactors is recommended for future research. Catalysis of microwave pyrolysis with LDO proved effective. The catalyst promoted the formation of volatiles (gas and liquid), even when present in small ratios. It also promoted the formation of esters and even anhydrides and small fractions of hydrocarbons at high catalyst ratios. The catalyst activity led to increased water yields. This indicated that it removes oxygen from the pyrolysis products, thereby improving their quality. The catalyst was believed to be limited by the low temperatures used in this investigation and higher temperatures might increase the release of CO2 and should be investigated. Significant reduction in the total acid number (TAN) and an improved dry-basis heating value were also achieved by the addition of the catalyst. The water content increased from 50% to 70%, the TAN reduced from 174 mg KOH/(g oil) to 72 mg KOH/(g oil), and the calorific value increased from 19.1 MJ/kg to 21.5 MJ/kg. / Dissertation (MEng)--University of Pretoria, 2017. / Chemical Engineering / MEng / Unrestricted

The hardwood Eucalyptus grandis has been shown to be an important commodity for forestry-related industries as it has significantly faster specific growth rates per annum when compared with other types of tree species. It has therefore been suggested that residues from E. grandis may be a useful source of biomass for use in the production of biofuels for the transportation industry. Notably, E. grandis plantations within the Southern Hemisphere have some of the fastest growth rates worldwide. Due to the inherent nature of biomasses, such as lignocellulosic types having a significant amount of oxygen present, upgrading of biofuels produced from E. grandis is necessary. Several approaches were therefore evaluated to upgrade pyrolysis oils produced from E. grandis so as to increase their calorific values by decreasing oxygen content and subsequently increasing the hydrogen ratio. The hydrogen-to-carbon (H/C) and oxygen-to-carbon (O/C) ratios may be used successfully to evaluate the performances of catalyst-based upgrading techniques for either in situ or ex situ pyrolysis. In this regard the van Krevelen diagram, in which biofuels can be compared for their suitability as transportation fuels, along with their respective calorific values, is useful. The pyro-gas chromatography/mass spectroscopy (GC/MS) equipment is useful for the rapid and accurate evaluation of different catalysts for fast pyrolysis applications, and it was used here to evaluate the performances of the catalysts bentonite and ZSM-5 zeolite for upgrading pyrolysis oil produced from E. grandis biomass. A van Krevelen diagram was used to evaluate the performance of these catalysts, in conjunction with calorific values, based on the higher heating values v for the pyrolysis oils. Further studies were completed for microwave pyrolysis as it is a less harsh form of pyrolysis based on energy-transfer mechanisms. Mass balances were done and demonstrated good repeatability, with more stable pyrolysis oils being produced. This stability may be attributed to similarities between microwave pyrolysis and hydrothermal liquefaction as microwave pyrolysis induces conditions comparable to those of hydrothermal liquefaction within the wood cells, and both methods produce a stable product called bio-crude. Furthermore, it was found that these pyrolysis oils could be distilled so as to remove some of the water content and improve the higher heating value (HHV) from 13.80 to 23.30 MJ/kg. However, this was not as high as the theoretical yield of 26.70 MJ/kg, and better performance was obtained for fast pyrolysis catalysed with ZSM-5 zeolite at 300 °C, which achieved an HHV of 34.54 MJ/kg. It is recommended that ZSM-5 zeolite catalysis be used in microwave-assisted vacuum pyrolysis to determine whether a similar improvement may be realised. Microwave-assisted pyrolysis should also be investigated as a possible technology for inducing conditions similar to hydrothermal liquefaction processes within the cells that make up the biomass. / Dissertation (MEng)--University of Pretoria, 2015. / Chemical Engineering / Unrestricted

京都大学 / 0048 / 新制・課程博士 / 博士(農学) / 甲第19196号 / 農博第2135号 / 新制||農||1034(附属図書館) / 学位論文||H27||N4942(農学部図書室) / 32188 / 京都大学大学院農学研究科森林科学専攻 / (主査)教授 吉村 剛, 教授 髙野 俊幸, 教授 渡邊 隆司 / 学位規則第4条第1項該当 / Doctor of Agricultural Science / Kyoto University / DFAM

Biomassa innehåller oorganiska ämnen som bl.a. alkalimetaller och alkaliska jordartsmetaller, vilket bidrar till ett minskat utbyte av pyrolysolja och ökar istället utbytet av gaser och lågvärdiga produkter. Detta sker p.g.a. att oorganiska ämnen agerar som krackningkatalysatorer. [1] Pyrolysolja har även en hög syrehalt vilket t.ex. gör den oblandbar med fossil olja. Genom att använda lakning som förbehandlingsmetod kan biomassans innehåll av oorganiska ämnen minska och pyrolysoljans sammansättning ändras. Detta sker genom bl.a. jonbytesreaktioner som uppstår mellan joner i lakningsmedlet och biomassans oorganiska ämnen. [2]        En katalysator kan användas för att minska syrehalten i pyrolysoljan och erhålla högvärdiga produkter som aromater. Detta sker genom katalytiska reaktioner som bl.a. krackning, aromatisering, ketoniserings- och aldolkondensation samt avspjälkning av vatten. [3] [4] I detta arbete har kombinationen av att förbehandla biomassa samt att låta pyrolysångor reagera över en katalysator undersökts. Fyra olika experiment har utförts för att kunna jämföra produktfördelningen mellan vätska, gas och kolrest, vätskefördelningen mellan H2O och olja samt olje-sammansättningen i de olika fallen. Experimenten utfördes med förbehandlad/icke-förbehandlad biomassa med och utan katalysator. Som lakningsmedel vid förbehandlingen användes en blandning av ättiksyra och avjoniserat vatten som biomassan behandlades med och sedan separerades ifrån. Som katalysator användes zeoliten HZSM-5 och utvärderades ex-bed i pyrolysören.        Resultaten visar att halten oorganiska ämnen minskar efter behandling. Förbehandlad biomassa utan katalysator ger ett ökat utbyte av vätska där vätskefördelningen mellan H2O och olja visar en större mängd olja jämfört med icke-förbehandlad biomassa utan katalysator. I fallet förbehandlad biomassan med katalysator visar resultatet att en större mängd gas bildas jämfört med icke-förbehandlad biomassa med katalysator, vilket tyder på att katalysatorn reagerar starkare mot sammansättningen av pyrolysångor från förbehandlad biomassa i det fallet. Vätskefördelningen vid icke-förbehandlad biomassan med katalysator visar en större mängd olja jämfört med förbehandlad biomassa med katalysator.       Olje-sammansättningen visar att den största mängden högvärdiga produkter, i detta fall polyaromatiska kolväten, bildas vid närvaro av katalysator. / Biomass generally contains inorganic substances such as alkali metals and alkaline earth metals, which reduce the yield of pyrolysis oil and increases the yield of gases and low-value products due to inorganic substances acting as cracking catalysts. [1] Pyrolysis oil also has a high oxygen content, making it im-miscible with fossil oil. Using leaching as a pretreatment method, the content of inorganic substances in biomass can decrease which changes the composition of the pyrolysis oil. Among other things, this occurs through ion-exchange reactions that occur when ions between the leachant and the ionically bonded inorganic elements in biomass change site. [2] A catalyst can be used to reduce oxygen content in the pyrolysis oil and obtain high-quality products such as aromatics. This is done through reactions such as cracking, aromatization, ketonization and aldol condensation as well as hydro-deoxygenation that arise in the presence of a catalyst. [3] [4]            In this work, four different experiments have been conducted to compare the product distribution between liquid, gas and char, the liquid distribution between H2O and oil and the oil composition in the different cases. The experiments were performed with pre-treated/untreated biomass with and without catalyst. As leachant, a mixture of acetic acid and deionized water was used with which the biomass was boiled and then separated. As catalyst, The zeolite HZSM-5 was used. HZSM-5 was evaluated ex-bed in the process. The results show that the content of inorganic substances decreases after treatment. Pre-treated biomass without catalytic upgrading leads to increase in the liquid yield in which the liquid distribution between H2O and oil shows a greater amount of oil compares to untreated biomass with without catalytic upgrading, indicating a decrease of inorganic substances. In the case of pre-treated biomass with catalyst, the result shows that a larger amount of gas is formed compared to untreated biomass with catalyst, which indicates that the catalyst reacts more strongly to the composition of pyrolysis vapors from a pre-treated biomass in that case. The liquid distribution of the untreated biomass with catalyst shows a greater amount of oil compared to pre-treated biomass with catalyst.       The oil composition shows that the largest amount of high-value products, in this case polyaromatic hydrocarbons, is formed in the presence of the catalyst.

Clean and efficient electricity can be generated using an Integrated Gasification Combined Cycle (IGCC). Although IGCC is typically used with coal, it can also be used to gasify other carbonaceous species like biomass and petroleum coke. It is important to understand the pyrolysis and gasification of these species in order to design commercial gasifiers and also to determine optimal conditions for operation. High heating-rate (100,000 K/s) pyrolysis experiments were performed with biomass (sawdust) in BYU's atmospheric flat-flame burner reactor at conditions ranging from 1163 to 1433 K with particle residence times ranging from 23 to 102 ms. Volatile yields and mass release of the sawdust were measured. The measured pyrolysis yields of sawdust are believed to be similar to those that would occur in an industrial entrained-flow gasifier since biomass pyrolysis yields depend heavily on heating rate and temperature. Sawdust pyrolysis was modeled using the Chemical Percolation Devolatilization model assuming that biomass pyrolysis occurs as a weighted average of its individual components (cellulose, hemicellulose, and lignin). Thermal cracking of tar into light gas was included using a first-order kinetic model. The pyrolysis and CO2 gasification of petroleum coke was studied in a pressurized flat-flame burner up to 15 atm for conditions where the peak temperature ranged from 1402 to 2139 K. The measured CO2 gasification kinetics are believed to be representative of those from an entrained-flow gasifier since they were measured in similar conditions of elevated pressure and high heating rates (100,000 K/s). This is in contrast to the gasification experiments commonly seen in the literature that have been carried out at atmospheric pressure and slow particle heating rates. The apparent first-order Arrhenius kinetic parameters for the CO2 gasification of petroleum coke were determined. From the experiments in this work, the ASTM volatiles value of petroleum coke appeared to be a good approximation of the mass release experienced during pyrolysis in all experiments performed from 1 to 15 atm. The reactivity of pet coke by CO2 gasification exhibited strong pressure dependence.

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