The work described in this dissertation focused on chemistry related to the use of aqueous sodium hydroxide as a treatment in the processing of wheat straw. A major emphasis was the comprehensive evaluation of straw component partitioning due to sodium hydroxide (NaOH) processing. This was evaluated over a range of NaOH concentrations (0­‐10%, w/v), all at 50°C, 5 h treatment period, and 3% solid loading. Solid and liquid phases resulting from NaOH treatments were evaluated. Total solids recovered in the NaOH­‐treated solid phase ranged from 47.4­‐88.0%. Overall carbohydrate recovery in the combined solid and liquid phases was negatively correlated with the alkali concentration of the treatment liquor. The glucan content of the NaOH‐treated solid phase ranged from 37.2­‐67.4%. Glucan recovery in the solid phase was relatively high in all cases, the minimum value being ~98%. Increasing amounts of xylan partitioned into the liquid phase as sodium hydroxide concentrations increased – it ranged from 31­‐83% of the xylan being recovered in the soluble phase. Carbohydrate analyses of the pretreated liquor revealed that the majority of carbohydrate loss from the solid fraction could be recovered in the liquid phase in form of oligomers and monomers due to alkaline degradation. The interconversion of glucose, fructose, and mannose under the alkaline condition played an important role in the presence of those sugars. Increase in NaOH concentration contributed to increase in amount of cellulose­‐derived and hemicellulose‐derived oligomers in the pretreated liquor. All oligomers except fructooligomers in NaOH pretreated liquor were higher than those found in water extraction at 50°C, 5 h. Total carbohydrate recovery from the solid and liquid fractions was as high as 99% for glucose and glucan in 5% NaOH treatment and 80‐95% for xylose and xylan in 1-­10% NaOH treatment. The presence of NaOH as extraction reagent dramatically induced lignin and ash removal from the pretreated solid with up to 63% acid insoluble lignin (AIL) and 87% ash extraction. Solid fractions resulting from NaOH pretreatments (up to 5% NaOH) were tested for their susceptibility to enzymatic saccharification using cellulase and cellulase/xylanase enzyme preparations. The cellulase/xylanase enzyme preparation was found to be more effective at cellulose saccharification than the cellulase enzyme preparation alone. Maximum glucose yield, which corresponded to the 5% NaOH treatment, was 82% over the standard 48 h saccharification period. Extended saccharifications times to 120 h showed that the conversion yield approached 90%. Sequential treatments of the straw (i.e. initial alkali treatment – first enzyme saccharification – second alkali treatment ‐ second enzyme treatment) revealed the NaOH treatment has the potential to render essentially all (~99%) of the straw glucan susceptible to enzyme saccharification. This suggests that the layered molecular arrangement of cellulose, hemicellulose, and lignin in the cell wall impacts biomass recalcitrance and glucan conversion yield. The other major focus of this dissertation research was the characterization of alkali neutralization, which occurs during the aqueous alkali processing of wheat straw. The approach taken was to evaluate the time course of alkali uptake and to determine the underlying nature of alkali uptake. The knowledge generated from this study is useful for understanding the nature of the alkali‐induced chemistry that is at the heart of alkali processing of agricultural byproducts, foods, and forest products. Alkali uptake/acid generation measurements were monitored for wheat straw suspensions at pH 11 and 30°C. The first phase of alkali uptake corresponded to the 30‐second time period over which the pH of the wheat straw suspension was adjusted from its original pH (~6.6) to pH 11. Alkali neutralization during this period was attributed to the instantaneous ionization of solvent accessible Bronstad acids. Following pH adjustment to 11.0, the time course of subsequent alkali uptake was recorded. The time course appeared biphasic. The early phase, which corresponded to the relatively rapid uptake of alkali, was evident during the first 24 hours. The later phase, which was characterized by the relatively slow uptake of alkali, was maintained for the length of the study (up to 96 hours). Alkali uptake during the early phase of the time course appears to be determined by the rate of hydrolysis of readily accessible esters – primarily acetic acid esters (acetyl groups). Alkali uptake during the later phase of the time course appears to be impacted by the rate of alkali penetration into the straw and the rate of production of alkali‐induced acid degradation products. The uptake of alkali in the pH adjustment phase was ~ 120 μEq per gram wheat straw, the uptake of alkali in the early phase of time course was ~ 1,064 μEq per gram wheat straw, and the rate of uptake in the later phase of the time course 6.10 μEq per gram wheat straw per hour. Amount of acetyl groups, ferulic acid, and p-­coumaric acid generated during 96-­h pretreatment revealed that they are major esters being hydrolyzed under the studied condition. Combined, these ester-­derived acids contributed up to ~ 28% of overall alkali uptake. In addition, alkaline degradation products quantified in this study showed additional ~ 28% contribution to the overall alkali uptake. / Graduation date: 2012

Description of the technological process of production and overview of materials applied in the brick-making industry, which are used for the manufacture of fired bricks.The introduction of ground straw as a new material for brick making, which should replace the currently processed sawdust, mainly due to the high price of timber.The result is an overall evaluation of useful characteristics, demands on processing these two materials and their mutual comparison from a technological and economic point of view.

Aus gegebenen klimatischen Gründen sind viele Milchviehbetriebe in Syrien gezwungen, Grobfutter aus weit entfernten Ackerbaugebieten heran zu transportieren. Im Falle des in die-ser Arbeit beschriebenen Unterschungsbetriebes werden jährlich etwa 400 Tonnen Futterstroh aus dem ca. 800 km entfernten Ackerbaugebiet herantransportiert. In dem Untersuchungsbe-trieb stellt Stroh über 80% des Grobfutters dar. Gegenwärtig wird das Stroh gehäckselt und in Plastik-Säcke gefüllt; dennoch werden die eingesetzten Transportzüge nur zu 45% ausgela-stet. Die Kosten der Kompaktierung und des Transports aus den Getreideanbaugebieten in die Milchviehbetriebe bestimmen im Wesentlichen die Kosten für das Stroh. Aus diesem Grunde konzentrierten sich die Untersuchungen darauf, in welchem Maße durch unterschiedliche Be-handlungsmethoden von Stroh dessen Einsatzmöglichkeiten in der Milchviehfütterung ver-bessert, die Transportaufwendungen reduziert und die Umwelt durch verringerten Treibstoff-verbrauch entlastet werden können. Untersucht wurden die Möglichkeiten zur Erhöhung der Transportleistung und zur Senkung der Aufwendungen bei gleichzeitiger Sicherung der Fut-terqualität, die insbesondere durch die mechanische und chemische Behandlung des Strohs erzielt werden können. Anhand der mechanischen und chemischen Behandlung von Stroh wurden die Möglichkeiten der Futterwerterhöhung des Strohs sowie eine angepaßte Rationsgestaltung durchgeführt. Da-bei erweist sich die Quaderballenlinie als das optimale Verfahren, das durch die Reduzierung des Kraftstoffverbrauchs für den Transport die CO2-Emission um 46% pro Jahr senkt. Die Strohbehandlung durch Zusatz von 4% Harnstoff und 50% Wasser (bezogen auf die Trocken-substanzmenge des Strohs) stellt eine optimale Lösung dar. Aufgrund dessen sollte der Anteil von Aufschlußstroh in der täglichen Ration auf 5 bis 8 kg TS / Kuh u. Tag (abhängig vom Laktationsstadium) erhöht werden. Die Effekte der Quadergroßballen und der anschließenden Harnstoffbehandlung am Ver-brauchsort bringen dem Betrieb eine finanzielle Entlastung von 13% seiner Jahresausgaben für Futtermittel. / Due to the unfavourable climatic conditions for forage production, dairy farms around Da-mascus (Syria) are forced to transport straw from far crop growing regions. The dairy farm covered in this study needs about 400 tonnes of straw to be used as feed which has to be transported from a distance of around 800 km. In the study farm straw covers more than 80% of the forage feed provided. At present the straw is chopped and is being transported in plastic sacks utilising only 45 % of the capacity of the trucks. This indicates the need for improve-ment in truck utilisation through optimisation process such as compacting. The cost of straw is mainly influenced by the cost of compacting and transporting the straw from crop producing regions to the dairy farms located at up to 800 km away from the pro-duction centre. This study was therefore undertaken to evaluate the different treatment methods such as physical (chopping, compacting, etc) and chemical (Urea application) in improving the utili-sation of straw as dairy feed. The study has also included the minimisation of transportation cost and reduction of pollution of the environment through an optimisation process. At the same time attempts were made to increase the transport capacity and reduction of the expendi-ture without affecting the quality of the feed. Through the physical and chemical treatments of straw it was possible to improve the feed value of straw which has enabled us to develop a new ration formulation that could be used on the study farm. The use of square bale to compact the straw has reduced diesel consumption which in turn minimises CO2 emission by 46% per year. The chemical treatment employed by using 4% Urea and 50% water of the straw weight was observed to be optimal. Based on the above chemical treatment procedure, an allowance of 5 to 8 kg DM per cow and day was recommended depending on the lactation stage of the cow. The effect of the square baling in conjunction with the Urea treatment at the dairy farm could reduce the yearly feed expenditure of the farm by 13%.