Carbon and Fossil Fuels

Biodiesel is produced in a pure form (referred to as “B100”or “neat biodiesel”) and is typically blended with petroleum-based diesel fuel. Such biodiesel blends are designated as BXX, where XX represents the percentage by volume of pure biodiesel contained in the blend (e.g.,“B5,” “B20”).

Usually derived from vegetable oils - soy is very popular these days, but animal fats can also be used - biodiesel is made through a chemical process called transesterification which essentially splits the oil into two parts: alkyl esters and glycerine; the esters are the fuel, while the leftover glycerine is often the byproduct.

Biomass feedstocks are the plant and algal materials used to derive fuels like ethanol, butanol, biodiesel, and other hydrocarbon fuels. Examples of biomass feedstocks include corn starch, sugarcane juice, soyabean, crop residues such as corn stover and sugarcane bagasse, purpose-grown grass crops, and woody plants.

Biodiesel blend is a mixer of methyl or ethyl esters derived from a broad variety of renewable sources such as vegetable oil, animal fat and recycled cooking oil. These esters are oxygenated organic compounds that can be used in compression ignition engines. Blend of 20% to 80 % with petroleum diesel significantly reduces carcinogenic emissions and gases that contribute to global warming. It can be used as a 20% blend in most diesel equipment with no or only minor modifications. B20 is the most commonly used biodiesel blend in the United States because it provides a good balance between material compatibility, cold weather operability, performance, emission benefits and costs. 

Biodiesel is a renewable alternative fuel created from vegetable oils, animal fats and greases through a chemical process. The chemical process involves reaction of natural oils with an alcohol in the presence of a catalyst (usually sodium hydroxide [$NaOH$] or potassium hydroxide [$KOH$] and then refining the mixture to create molecules which can be easily burned in a diesel engine.

Molasses is a factory waste from sugar industry. It does not contain any traces of methane. So, methane is not obtained from molasses.

Hydrogen gas is considered as the cleanest fuel because when hydrogen burns in air, it produces nothing but water vapour.

Higher the methane content, higher the calorific value. Pure $CH _4$ has a Gross Calorific Value of 39.8 $MJ/m^3$. the rate of combustion of biogas is quite high as it is produced by anaerobic decomposition of animal and plant waste.
It does not leave any ash behind after burning as cow dung and other organic matter is used in the preparation of biogas.

When dead plants get buried into the bottom of the soil they are slowly converted into coal due to high pressure and high temperature. Heat and pressure produced chemical and physical changes in the plant layers which forced out oxygen and left rich carbon deposits. In time, material that had been plants became coal.

Since coal is a form of sedimentary rock, it's is hard and porous. It is black due to its prime composition of carbon, compressed at high temperature and pressure.

Coal tar is basically seen as very thick liquid used in making roads. Hence it is more viscous in nature than coal.

Naphthalene is industrially prepared from coal tar. 

Coal tar is used in producing industrially dyes, paints, photographic plates etc.