Concept explainers
• describe the chemical processes used in biomass production and conversion to biofuels.
Interpretation: The chemical processes used in biomass production and conversion of biomass to biofuels should be described.
Concept Introduction: In the biomass production, organic materials are converted into some form which can be used to produce bio-energy.
This is defined as increase in the organic matter concentration, this production adds the organic matter in the given area. Biomass is a renewable source of energy as it is obtained from plants and animals waste.
Explanation of Solution
In the biomass production, there are two types of productions as explained below:
Primary production: This is the energy obtained by plants by the process of photosynthesis. The excess energy is stored and added to the total biomass of the ecosystem.
Secondary production: This is defined by the absorption of the organic matter by tissues of the organisms. The ingestion by animals comes under this category. The process involves the decomposition of organic matter with the help of microorganisms.
Now, biomass to biofuel conversion is most important step in the agricultural world. Biomass is referred to the waste like trees, grass and other garden waste in the agriculture. This process can reduce the emission of greenhouse gases in the environment. This also balances the ecology. The process of biomass conversion directly uses the energy and the amount of energy used depends on the technique applied for the conversion.
There are main two types of conversions:
- Thermal conversion
- Chemical conversion
Thermal conversion: As the name suggests, in thermal conversion, heat plays an important role in biomass conversion.
This is further divided into three steps:
- Combustion
- Gasification
- Pyrolysis
The first process involved the combustion of biomass, the efficiency of this method of conversion is very low and it also affects the environment.
In gasification, the biomass is heated at very high temperatures in the presence of oxygen but in the controlled amount.
The pyrolysis involves the heating of biomass at very high temperatures in the absence of oxygen.
Chemical conversion: This process uses enzymes and microorganisms for the breakdown of biomass. The sub-processes are as follows:
Anerobic digestion: This converts biomass to methane.
Fermentation: This converts starch to ethanol and used in the manufacturing of alcohol
Composting: In this process, dry organic matter is decomposed aerobically in the presence of microorganisms. This is commonly used to produce heat.
Want to see more full solutions like this?
Chapter 3 Solutions
Chemistry for Engineering Students
- A newspaper article states that biomass has actually been used as an energy source throughout human history. Do you agree or disagree with this statement? Defend your answer.arrow_forward4.60 Why are fuel additives used?arrow_forwardThe carbon dioxide exhaled in the breath of astronauts is often removed from the spacecraft by reaction with lithium hydroxide 2LiOH(s)+CO2(g)Li2CO3(s)+H2O(l) Estimate the grams of lithium hydroxide required per astronaut per day. Assume that each astronaut requires 2.50 103 kcal of energy per day. Further assume that this energy can be equated to the heat of combustion of a quantity of glucose, C6H12O6, to CO2(g) and H2O(l). From the amount of glucose required to give 2.50 103 kcal of heat, calculate the amount of CO2 produced and hence the amount of LiOH required. The H for glucose(s) is 1273 kJ/mol.arrow_forward
- Ethanol, C2H5OH, is a gasoline additive that can be produced by fermentation of glucose. C6H12O62C2H5OH+2CO2 (a) Calculate the mass (g) of ethanol produced by the fermentation of 1.000 lb glucose. (b) Gasohol is a mixture of 10.00 mL ethanol per 90.00 mL gasoline. Calculate the mass (in g) of glucose required to produce the ethanol in 1.00 gal gasohol. Density of ethanol = 0.785 g/mL. (c) By 2022, the U. S. Energy Independence and Security Act calls for annual production of 3.6 1010 gal of ethanol, no more than 40% of it produced by fermentation of corn. Fermentation of 1 ton (2.2 103 lb) of corn yields approximately 106 gal of ethanol. The average corn yield in the United States is about 2.1 105 lb per 1.0 105 m2. Calculate the acreage (in m2) required to raise corn solely for ethanol production in 2022 in the United States.arrow_forwardA rebreathing gas mask contains potassium superoxide, KO2, which reacts with moisture in the breath to give oxygen. 4KO2(s)+2H2O(l)4KOH(s)+3O2(g) Estimate the grams of potassium superoxide required to supply a persons oxygen needs for one hour. Assume a person requires 1.00 102 kcal of energy for this time period. Further assume that this energy can be equated to the heat of combustion of a quantity of glucose, C6H12O6, to CO2(g) and H2O(l). From the amount of glucose required to give 1.00 102 kcal of heat, calculate the amount of oxygen consumed and hence the amount of KO2 required. The ff0 for glucose(s) is 1273 kJ/mol.arrow_forward4.61 What is actually measured by the octane ratings of different grades of gasoline?arrow_forward
- Insoluble AgCl(s) precipitates when solutions of AgNO3(aq) and NaCl(aq) are mixed. AgNO3(aq) + NaCl(aq) AgCl(s) + NaNO3(aq) rH = ? To measure the energy evolved in this reaction, 250. mL of 0.16 M AgNO3(aq) and 125 mL of 0.32 M NaCl(aq) are mixed in a coffee-cup calorimeter. The temperature of the mixture rises from 21.15 C to 22.90 C. Calculate the enthalpy change for the precipitation of AgCl(s), in kJ/mol. (Assume the density of the solution is 1.0 g/mL and its specific heat capacity is 4.2 J/g K.)arrow_forwardWhen one mole of ethylene gas, C2H4, reacts with fluorine gas, hydrogen fluoride and carbon tetrafluoride gases are formed and 2496.7 kJ of heat are given off. What is Hf for CF4(g)?arrow_forward4.1 List at least two factors that make it difficult to describe the combustion of gasoline accurately. What assumption can be made to address these complications?arrow_forward
- Graphite is burned in oxygen to give carbon monoxide and carbon dioxide. If the product mixture is 33% CO and 67% CO2 by mass, what is the heat from the combustion of 1.00 g of graphite?arrow_forwardCarbon dioxide from the atmosphere weathers, or dissolves, limestone (CaCO3) by the reaction CaCO3(s)+CO2(g)+H2O(l)Ca2(aq)+2HCO3(aq) Obtain H for this reaction. See Table 6.2 for the data.arrow_forwardAcetone, (CH3)2CO, is an important industrial compound. Although its toxicity is relatively low, workers using it must be careful to avoid flames and sparks because this compound burns readily in air. Write the balanced equation for the combustion of acetone.arrow_forward
- Chemistry for Engineering StudentsChemistryISBN:9781337398909Author:Lawrence S. Brown, Tom HolmePublisher:Cengage LearningChemistry: Matter and ChangeChemistryISBN:9780078746376Author:Dinah Zike, Laurel Dingrando, Nicholas Hainen, Cheryl WistromPublisher:Glencoe/McGraw-Hill School Pub CoWorld of Chemistry, 3rd editionChemistryISBN:9781133109655Author:Steven S. Zumdahl, Susan L. Zumdahl, Donald J. DeCostePublisher:Brooks / Cole / Cengage Learning
- General Chemistry - Standalone book (MindTap Cour...ChemistryISBN:9781305580343Author:Steven D. Gammon, Ebbing, Darrell Ebbing, Steven D., Darrell; Gammon, Darrell Ebbing; Steven D. Gammon, Darrell D.; Gammon, Ebbing; Steven D. Gammon; DarrellPublisher:Cengage LearningWorld of ChemistryChemistryISBN:9780618562763Author:Steven S. ZumdahlPublisher:Houghton Mifflin College DivChemistry: The Molecular ScienceChemistryISBN:9781285199047Author:John W. Moore, Conrad L. StanitskiPublisher:Cengage Learning