This master’s thesis is aimed at process of enzymatic hydrolysis of lignocellulosic material – waste paper as a source of raw material for production of liquid biofuels. In the theoretical part of this work are summarized previously used methods of hydrolysis and lignocellulosic materials used for the process of hydrolysis as a source of fermentable sugars for fermentation technology. The different types of waste paper are evaluated from the composition and usability with consideration to the papermaking process in order to select the appropriate type of waste paper for the enzymatic hydrolysis process. In the next part of this work are suggested technological premises and procedures for the preparation of raw materials and the subsequent enzymatic hydrolysis of these pre–treated materials. In the experimental part were optimized parameters of enzymatic hydrolysis using the Novozymes company enzyme package. Enzymatic degradation of cellulose to reducing sugars was observed using Somogyi – Nelson method. For the verification of hydrolysis conditions were used model materials with high cellulose content – pulp and filter paper. Conditions, which seems to be the best after testing on the model materials, were verified on specific waste paper materials – offset cardboard, recycled paper, matte MYsol paper and for comparison again on model materials – pulp and filter paper. The highest yields was achieved with the use of cardboard, which was further tested using various combinations of pretreatment to material for purpose of increase the yields of hydrolysis.

Submitted by Johnny Rodrigues (johnnyrodrigues@ufcg.edu.br) on 2018-03-21T16:54:52Z No. of bitstreams: 1 DÉBORA JAMILA NÓBREGA DE MELO - DISSERTAÇÃO PPGEQ 2015..pdf: 1660411 bytes, checksum: 435dc571b5f61082152afe1a09c340cb (MD5) / Made available in DSpace on 2018-03-21T16:54:52Z (GMT). No. of bitstreams: 1 DÉBORA JAMILA NÓBREGA DE MELO - DISSERTAÇÃO PPGEQ 2015..pdf: 1660411 bytes, checksum: 435dc571b5f61082152afe1a09c340cb (MD5) Previous issue date: 2015-09 / CNPq / Diante da futura escassez dos recursos energéticos originados do petróleo e seus derivados, aliados aos impactos ambientais causados pelo consumo desenfreado de recursos naturais, faz-se necessário a busca por produção de energias alternativas e limpas. Nesse ínterim, surgem as microalgas como potenciais de produção de biocombustíveis, por sua elevada taxa de crescimento e capacidade produtiva de lipídios e carboidratos. Porém, o alto custo de manutenção ainda inviabiliza sua produção. Dessa forma, esse trabalho busca aumentar a produção de microalgas utilizando a vinhaça, um resíduo da indústria sucroalcooleira altamente nutritivo e poluidor, e reutilizando resíduos do próprio cultivo como suplementação nutricional ao meio de cultura. A microalga Chlorella sp. foi cultivada em meio Bold’s Basal Medium (BBM) modificado, suplementado com de 5, 10 e 15% de vinhaça e resíduos de cultivos com diferentes concentrações, reutilizados por até três vezes. O sistema de cultivo adotado foi o mixotrófico. Foram calculadas as velocidades específicas de crescimento máximas e os tempos de geração dos cultivos suplementados com vinhaça e resíduos de cultivos. Calcularam-se as remoções de Demanda Química de oxigênios dos cultivos suplementados com vinhaça. Foram quantificados os teores de açúcares redutores e lipídios das biomassas cultivadas com 10% de vinhaça e sem suplementação. Foi verificado que os cultivos suplementados com 5 e 10% de vinhaça apresentaram maior densidade celular que o cultivo sem suplementação. As taxas de crescimento máximas e os tempos de geração dos cultivos com 5 e 10% de vinhaça foram muito próximas, diferente do cultivo suplementado com 15% de vinhaça que apresentou inibição no crescimento. As remoções de DQO foram elevadas e em média 85%. A utilização dos resíduos de cultivos favoreceu o crescimento das microalgas, apresentando melhores resultados os cultivos suplementados com resíduos de segunda reutilização, em especial os cultivos suplementados com resíduos originados de um cultivo com adição de vinhaça. A biomassa da Chlorella sp. cultivada com suplementação de 10% de vinhaça apresentou 11,50% de lipídios, 0,33% de açúcares redutores. Estudos mais aprofundados devem ser realizados para uma melhor caracterização da biomassa para verificar a influência da suplementação do meio com vinhaça na produção de proteínas e carboidratos totais. / In the face of future scarcity of energy resources derived from oil and its derivatives, coupled with the environmental impacts caused by rampant consumption of natural resources, it is necessary to search for a renewable and clean energy. In the meantime, there are microalgae with potential of biofuel production due to its high growth rate and productivity capacity of lipids and carbohydrates. However, the high cost of maintenance still prevents its manufacture. In this way, the present work aims to increase the production of microalgae using vinasse which is a residue of highly nutritious sugarcane industry and a polluter, and reusing waste from the own cultivation as a nutritional supplement to the culture medium. The microalgae Chlorella sp. was grown in a modified Bold's Basal Medium (BBM), supplemented with 5, 10 and 15% of vinasse and residues of cultivations with different concentrations in what they were reused at maximum of three times. The adopted cultivation system was the mixotrophic. Calculations were made to obtain the specific maximum speed of growth and the generation times of cultivations supplemented with vinasse and cultivation waste. Also, it was calculated the removals of Chemical Oxygen Demand (COD) of cultivations supplemented with vinasse. For the next step, it was quantified the reducing sugars and lipids of biomass cultivated with 10% of vinasse and without supplementation. It was verified that the cultivation supplemented with 5 and 10% of vinasse showed higher cell density than the unsupplemented cultivation. The maximum growth rates and generation times of cultivations with 5 and 10% of vinasse were very close whereas cultivation supplemented with 15% of vinasse showed growth inhibition. The removals of COD were high and averaged at 85%. The use of cultivation residue has favored the microalgae growth, presenting best results for the cultures supplemented with second reuse waste, in particular cultures supplemented with residues derived from a culture with addition of vinasse. The biomass of cultivated Chlorella sp. with supplementation of 10% of vinasse showed 11.50% lipids, 0.33% of reducing sugars. Further studies should be performed to better characterize the biomass to check the influence of the medium supplementation with vinasse in the production of proteins and total carbohydrates.

In order to satisfy the global requirement for transport fuel sustainably, renewable liquid biofuels must be developed. Currently, two biofuels dominate the market; bioethanol for spark ignition and biodiesel for compression ignition engines. However, both fuels exhibit technical issues such as low energy density, poor low temperature performance and poor stability. In addition, bioethanol and biodiesel sourced from first generation feedstocks use arable land in competition with food production, and can only meet a fraction of the current demand. To address these issues it is vital that biofuels be developed from truly sustainable sources, such as lignocellulosic waste resources, and possess improved physical properties. To improve and control the physical properties of a fuel for specific application, one must be able to tailor the products formed in its production process. All studies within this thesis, therefore, have the aim of assessing the fuels produced for their variability in physical property, or the aim of directing the process considered to specific fuel molecules. In Chapter 2, spent coffee grounds from a range of geographical locations, bean types and brewing processes were assessed as a potential feedstock for biodiesel production. While the lipid yield was comparable to that of conventional biodiesel sources, the fatty acid profile remained constant irrespective of the coffee source. Despite this lack of variation, the fuel properties varied widely, presumably due to a range of alternative biomolecules present in the lipid. Though coffee biodiesel was produced from a waste product, the fuel properties were found to be akin to palm oil biodiesel, with a high viscosity and pour point. The blend level would therefore be restricted. In Chapter 3 the coffee lipid, as well as a range of microbial oils potentially derived from renewable sources were transformed into a novel aviation and road transport fuel through cross-metathesis with ethene. Hoveyda-Grubbs 2nd generation catalyst was found to be the most suitable, achieving 41% terminal bond selectivity under optimum conditions. Metathesis yielded three fractions: an alkene hydrocarbon fraction suitable for aviation, a shorter chain triglyceride fraction that upon transesterification produced a short chain biodiesel fuel, and a multifunctional volatile alkene fraction that could potentially have application in the polymer industry. Though there was variation for the road transport fuel fraction due to the presence of long chain saturates, the compounds fell within the US standard for biodiesel. The aviation fraction lowered the viscosity, increased the energy density, and remained soluble with Jet A-1 down to the required freezing point. Oleaginous organisms generally only produce a maximum of 40% lipid, leaving a large portion of fermentable biomass. In Chapter 4, a variety of ethyl and butyl esters of organic acids – potentially obtainable from fermentation – were assessed for their suitability as fuels in comparison to bioethanol. One product, butyl butyrate, was deemed suitable as a Jet A-1 replacement while four products, diethyl succinate, dibutyl succinate, dibutyl fumarate and dibutyl malonate, were considered as potential blending agents for diesel. Diethyl succinate, being the most economically viable of the four, was chosen for an on-engine test using a 20 vol% blend of DES (DES 20) on a chassis dynamometer under pseudo-steady state conditions. DES20 was found to cause an increase in fuel demand and NOx emissions, and a decrease in exhaust temperature, wheel force, and CO emissions. While fermentation is generally directed to one product, producing unimolecular fuels, they do not convert the entirety of the biomass available. An alternative chemical transformation is pyrolysis. In Chapter 5, zeolite-catalysed fast pyrolysis of a model compound representative of the ketonic portion of biomass pyrolysis vapour – mesityl oxide – was carried out. The aim of this study was to understand the mechanistic changes that occur, which could lead to improved bio-oil yields and more directed fuel properties of the pyrolysis oil. While HZSM-5 and Cu ZSM-5 showed no activity for hydrogenation and little activity for oligomerisation, Pd ZSM-5 led to near-complete selective hydrogenation of mesityl oxide to methyl isobutyl ketone, though this reduced at higher temperatures. At lower temperature (150-250 °C), a small amount of useful oligomerisation was observed, which could potentially lead to a selective pyrolysis oligomerisation reaction pathway.