5. Chemical Processes Products are being used as fuel for the transport From either petrol-based material or from biomass The most common biofuels Used for transport purposes DME, methanol, ethanol, butanol and diodiesel

The simplest ether that is a gas at normal temperature and pressure Dimethy Ether (DME) 5-1. Dimethy Ether (DME) The simplest ether that is a gas at normal temperature and pressure Non-carcinogenic / highly flammable / CH3OCH3 Used fuel in diesel engines or blended with diesel High cetane number (55-60) > diesel (40-55) Short ignition time and better combustion than diesel Under pressure, in liquid form DME can be produced from synthesis gas or fossil raw material Biomass using the gasification method Dehydration of methanol to DME 5-2. Biodiesel 5-3. Rapeseed Methyl Ester (RME) 5-4. Primary Alcohols 5-5. Ethanol from Sugar Feedstock 5-6. Ethanol from Starchy Feedstock 5-7. Ethanol from Cellulose Feedstock

Fuel made from natural (biological) renewable resources Biodiesel 5-2. Biodiesel Fuel made from natural (biological) renewable resources Used directly in conventional diesel motors (engines) Advantages compared to diesel produce Degradable / non-toxic / contains no sulfur Releases less emissions during combustion Transesterification => vegetable oil Quality changes with storage (oxidative and hydrolytic reaction) One of the most common kinds of biodiesel : rapeseed methyl ester 5-1. Dimethy Ether (DME) 5-3. Rapeseed Methyl Ester (RME) 5-4. Primary Alcohols 5-5. Ethanol from Sugar Feedstock 5-6. Ethanol from Starchy Feedstock 5-7. Ethanol from Cellulose Feedstock

Rapeseed Methyl Ester (RME) Alternative biofuel (diesel engines) Advantages compared to diesel produced Non-toxic and less flammable Same cetane number, viscosity and density as diesel No aromatic compounds Produced from vegetable oils (rapeseed: 3 ton / hectare) By-product of transestrification reaction Glycerol : used in the cosmetics industry Protein-rich cake: stock feed Not possible to cultivate rapeseed every year (up to 4-6 years) 5-1. Dimethy Ether (DME) 5-2. Biodiesel 5-4. Primary Alcohols 5-5. Ethanol from Sugar Feedstock 5-6. Ethanol from Starchy Feedstock 5-7. Ethanol from Cellulose Feedstock

Rapeseed Methyl Ester (RME) Transesterification of triglycerides to methyl ester and glycerol 5-1. Dimethy Ether (DME) 5-2. Biodiesel 5-4. Primary Alcohols 5-5. Ethanol from Sugar Feedstock 5-6. Ethanol from Starchy Feedstock 5-7. Ethanol from Cellulose Feedstock

Liquid bio-fuels (methanol, ethanol and butanol) Primary Alcohols 5-4. Primary Alcohols Liquid bio-fuels (methanol, ethanol and butanol) From sugarcane, sugar beet, wheat, barley, corn raw sugar, switch grass, agricultural residues, wood and many industrial wastes and corn stover The most important characteristic of alcohols : octane number 0 = n-heptane 100 = iso-octnae (2,2,4-trimethyl pentane) Ethanol and methanol have low centane numbers (8 and 5) Only possible to use them in diesel engines 5-1. Dimethy Ether (DME) 5-2. Biodiesel 5-3. Rapeseed Methyl Ester (RME) 5-5. Ethanol from Sugar Feedstock 5-6. Ethanol from Starchy Feedstock 5-7. Ethanol from Cellulose Feedstock

Produced can be used to make other related chemicals Primary Alcohols 5-4. Primary Alcohols 5-1. Dimethy Ether (DME) 5-2. Biodiesel 5-3. Rapeseed Methyl Ester (RME) 5-5. Ethanol from Sugar Feedstock 5-6. Ethanol from Starchy Feedstock 5-7. Ethanol from Cellulose Feedstock Cetane number : 15 = hepta methyl nonane 100 = n-hexadecane Produced can be used to make other related chemicals Ethyl acetate / acetic acid / acetaldehyde Oxidation / esterification

Methanol Colorless liquid without any particular smell at room temperature High toxic, corrosive and flammable Degradable relatively quickly / little harm to the environment Produced from fossil fuel and biomass (cellulose material) Gasfication (high temperature and pressure) Blended with gasoline M85 (85% methanol+15% gasoline)

Ethanol Colorless liquid / used in many ways as a chemical With regard to safety and environmental issues Less toxic than gasoline, diesel or methnol Broken down by bacteria to carbon dioxide and water Blended with gasoline (add emulsifying agent /used otto engines) E85 (85% ethanol+15% gasoline) Raw material : Cellulose, waste from paper mills, excess wine by fermentation of carbohydrates (sugar) Sugarcane, sugar beet, corn

Butanol Many similarities to bioethanol / comparative advantage Easy to blend with gasoline in higher concentrations without any harm to engines Higher energy content (30% higher) Better able to tolerate water contamination Low vapor pressure : easier to blend ethanol with gasoline Without and modification to the engine by fermentation of carbohydrates (same bioeethanol) Sugarcane, sugar beet, corn

Ethanol from Sugar Feedstock 5-1. Dimethy Ether (DME) 5-2. Biodiesel 5-3. Rapeseed Methyl Ester (RME) 5-4. Primary Alcohols 5-6. Ethanol from Starchy Feedstock 5-7. Ethanol from Cellulose Feedstock Ethanol from Sugarcane Ethanol from Sugar Beet

Ethanol from Sugarcane Easiest and most efficient processes 15% sucrose Brazil > USA Glycosidic bond can be broken down into two sugar unit, which are free and readily available for fermentation. The remaining solid from the pressing is fibrous and usually used as a fuel in the sugar mill. The cheapest bioethanol produced is from sugarcane in Brazil and the second cheapest is made from corn in the USA.

Ethanol from Sugar Beet Large amounts of sucrose. Disaccharide Most of the european countries and russia, together with the US produce most of the sugar beet in the world.

Ethanol from Starchy Feedstock 5-1. Dimethy Ether (DME) 5-2. Biodiesel 5-3. Rapeseed Methyl Ester (RME) 5-4. Primary Alcohols 5-5. Ethanol from Sugar Feedstock 5-7. Ethanol from Cellulose Feedstock Ethanol from Cereal Grains Ethanol from Corn and Corn Stover

Ethanol from Cereal Grains Process steps: Milling of grains Hydrolysis of starch to sugar units Fermentation by yeast Distillation Removal of water from ethanol. Distillation increases the ethanol concentration up to about 95%. In order to remove the rest of the water from the ethanol solution it must be dried by different drying agents to a concentration of 99.9% ethanol, or absolute ethanol. It is possible to produce 1L of absolute ethanol from about 3kg of wheat.

Ethanol from Corn and Corn Stover Most common feedstock Widely used in the USA Two carbohydrates : glucose and xylose The starch in corn is converted to glucose after grinding in a dry mill, reacting it with dilute acid and then reacting it with amylases. The free glucose is then available for fermentation to ethanol. Today, it is possible to use those parts of the plant, the stover, which includes stalk and leaves, as raw material for ethanol production. ethanol production from corn stover is more effective when enzymatic hydrolysis and fermentation are performed simultaneously, often called SSF, instead of SHF. delignification of pretreated corn stover improves enzymatic hydrolysis, but is a costly step and may cause some loss of sugar units.

Ethanol from Cellulose Feedstock 5-1. Dimethy Ether (DME) 5-2. Biodiesel 5-3. Rapeseed Methyl Ester (RME) 5-4. Primary Alcohols 5-5. Ethanol from Sugar Feedstock 5-6. Ethanol from Starchy Feedstock Cellulose-rich biomass Wood Switch grass Reed canary grass Crop residues from food Ethanol from lignocellulosic material includes two processes: Chemical – Hydrolysis Biological hydrolysis - Fermentation

Scheme of ethanol production from cellulose feedstock (p172 F.6.7) Ethanol from Cellulose Feedstock 5-7. Ethanol from Cellulose Feedstock 5-1. Dimethy Ether (DME) 5-2. Biodiesel 5-3. Rapeseed Methyl Ester (RME) 5-4. Primary Alcohols 5-5. Ethanol from Sugar Feedstock 5-6. Ethanol from Starchy Feedstock Scheme of ethanol production from cellulose feedstock (p172 F.6.7)

Ethanol from Cellulose Feedstock 5-1. Dimethy Ether (DME) 5-2. Biodiesel 5-3. Rapeseed Methyl Ester (RME) 5-4. Primary Alcohols 5-5. Ethanol from Sugar Feedstock 5-6. Ethanol from Starchy Feedstock CHAP Process CASH Process Ethanol from Switch Grass Ethanol from Reed Canary Grass Ethanol from Alfalfa

CHAP Process Based on the : Disadvantage Cellulose-rich material lignocellulosic material Low temperature Hydrochloric acid Disadvantage Corrosion problem High capital investment Dangers associated with concentrated acid Dioxin emissions This process was developed for cellulose-rich raw materials since high concentration of the acid may cause degradation of the pentoses in hemicellulose to furfural derivatives. The ethanol yield is usually about 35%. corrosion problems and the need for higher capital investment and dangers associated with the recovery of the concentrated acid make this method less attractive. during combustion of lignin that is contaminated with hydrochloric acid there is some risk of dioxin emissions.

CASH Process Based on the : Sawdust Residues from trees Hydrolysis – dilute sulfuric acid at a 200°C Fermentation – sugars by yeast to ethanol It has been shown that by using SO2 and dilute sulfuric acid in two steps, this increases the sugar and ethanol yield, since the amount of inhibitors such as furfural is decreased. the ethanol yield is about 30% of the energy in the raw material and there are also by-products, with up to 40% of the energy content in solid form, which can be used as biofuel.

Ethanol from Switch Grass Perennial C4 species Grown in central USA Remove lignin and hemicelluloses This grass is grown in central USA as a fodder crop or for soil conservation. The lignocellulosic biomass has been used to produce ethanol with various yields. By pretreating the raw material to remove lignin and hemicelluloses, it is possible to significantly improve the hydrolysis of cellulose.

Ethanol from Reed Canary Grass Perennial, 2m tall, upright straw, broad leaves, long panicle Grows naturally Consist of Various material This grass grows naturally in EU, asia and north america, especially in wet and humus-rich soil. Reed canary grass consists mainly of cellulose, hemicellulose and lignin, but also proteins, lipids and a relatively high content of inorganic material. The main sugars after hydrolysis of reed canary grass are glucose, xylose and also arabinose; the amount of hexose in the stem varies between 38 and 45% of the dry weight of the material and pentose about 22-25%. The lignin content varies between 18 and 21% of the dry weight. the grass has very good potential as an alternative and a complement to short rotation woody crops and also to softwood feedstocks such as spruce, for ethanol production in the future.

Ethanol from Alfalfa Fuel, feed and industrial materials Consists of various material Alfalfa consists mainly of celluloses, hemicelluloses, lignin, pectin and proteins. Therefore, it is a potential feedstock for ethanol production and also other chemicals.

6. Power Generation from Biomass Renewable resource Adventage Low cost of biomass compared to fossil fuel. Security of supply and reduction of transport distances since biomass is often locally produced and some part of biomass can be used in electricity production. No net CO2 emissions. Improvements of the economics of fuel production from biomass, since the electricity generated as a by-product can be used or sold and so reduce production costs dramatically Two interesting biomasses are corn and corn stover, since corn has been produced for food and also ethanol production in many countries and corn stover has been used in ethanol production and also recently pelletised with very good results in generating heat and power. Combining heat and power production from biomass is a very common concept in many industries.

Several types of fuel cell Fuel Cells Several types of fuel cell Alkaline fuel cell (AFC) Direct methanol fuel cell (DMFC) Polymer electrolyte fuel cell (PEFC) Phosphoric acid fuel cell (PAFC) Solid oxide fuel cell (SOFC) operating at high temperatures(500-1000°C) Molten carbonate fuel cell (MCFC) Proton exchange membrane fuel cell (PEMFC) A fuel cell is an electrochemical process for the production of electrical energy and heat. The concept is that chemical energy is converted into electricity and also heat without any combustion step. The process is clean(no emissions) and quite and also effective compared to conventional combustion engines. The excess heat from fuel cells can be used to heat water. A fuel cell usually consists of an electrolyte surrounded (encased) by two electrodes : a negative electrode (anode) and a positive electrode (cathode). 6-1. Fuel Cells

𝐶𝐻 3 𝑂𝐻+ 𝐻 2 𝑂 → 𝐶𝑂 2 +6 𝐻 + +6 𝑒 − (𝑎𝑚𝑜𝑑𝑒) Fuel Cells 6-1. Fuel Cells 𝐶𝐻 3 𝑂𝐻+ 𝐻 2 𝑂 → 𝐶𝑂 2 +6 𝐻 + +6 𝑒 − (𝑎𝑚𝑜𝑑𝑒) 1.5 𝑂 2 +6 𝐻 + +6 𝑒 − →3 𝐻 2 𝑂 (𝑐𝑎𝑡ℎ𝑜𝑑𝑒) In the direct methanol fuel cell(DMFC), an aqueous solution of ethanol is oxidised at the anode and reduced at the cathode. The methanol concentration plays a significant role in keeping a stable power output.

Principle of operation of DMFC to produce electricity (p175 F.6.8) Fuel Cells 6-1. Fuel Cells Principle of operation of DMFC to produce electricity (p175 F.6.8)

Fuel Cells 6-1. Fuel Cells In a fuel cell, oxygen and hydrogen are released by oxidation of methanol producing electricity. The electricity generated in a fuel cell can be used to power some vehicles instead of direct combustion of other fuels. El-vehicles are quite, more effective and produce no emissions compared to fossil fuel-using vehicles. There are three types of vehicles using electricity as the energy source: Rechargeable battery vehicles, limited electricity El-hybrid vehicles, one el-engine and one combustion engine Fuel cells vehicles, one el-engine

Fuel Cells Conclusion Fuel cells can be used in the next generation of vehicles as energy source