The invention relates to a hydrocarbon blend for input to a refinery and comprising a first blend component containing a renewable hydrocarbon component and a second blend component containing petroleum derived hydrocarbon to form at least part of a final hydrocarbon blend for processing in a refinery where the first blend component is characterized by comprising a hydrocarbon substance with at least 70% by weight having a boiling point above 220° C. and by having the characteristics (δ.sub.d1, δ.sub.ρ1, δ.sub.h1)=(17-20, 6-12, 6-12) and; where the second blend component is characterised by having the characteristics (δ.sub.{acute over (α)}2, δ.sub.ρ2, δ.sub.h2)=(17-20, 3-5, 4-7), where the first blend component is present in the final hydrocarbon blend in a relative amount of up to 80 wt %.

Marine diesel fuel/fuel blending component compositions and fuel oil/fuel blending component compositions are provided that are derived from crude oils having high naphthenes to aromatics volume and/or weight ratios and a low sulfur content. In addition to having a high naphthenes to aromatics ratio, a low sulfur content, and a low but substantial content of aromatics, such fuels and/or fuel blending components can have a reduced or minimized carbon intensity relative to fuels derived from conventional sources. The unexpected ratio of naphthenes to aromatics contributes to the fuels and/or fuel blending components further having additional unexpected properties, including low density, low kinematic viscosity, and/or high energy density.

A biodiesel composition comprising a stabilization agent is disclosed. The stabilization agent comprises depolymerized lignin having a weight average molecular weight of at least 360 g/mol and at most 5000 g/mol, and the TEAC value of the depolymerized lignin is at most 50% of the TEAC value of a corresponding lignin before having been depolymerized, and wherein the weight average molecular weight of the depolymerized lignin is at most 60% of the weight average molecular weight of the corresponding lignin.

A process of generating an alkyl ester of a fatty acid (e.g., a biodiesel) from a free fatty acid-containing substance (e.g., a feedstock), is provided. The process is effected by contacting a mixture of the free fatty acid-containing substance and a respective alcohol with Lewis Acid; and, while contacting, exposing the mixture and the Lewis acid to ultrasound energy. An alkyl ester of a fatty acid, or a mixture of two or more alkyl esters of fatty acids, (e.g., a biodiesel), obtainable by the process, are also provided.

A method for forming poly(dimethoxymethane) includes a step of separating a formaldehyde-containing blend into a first bottom stream and a first top stream. The first formaldehyde-containing blend includes methanol, formaldehyde, and water while the first bottom stream includes water. The first top stream includes dimethoxymethane that is produced from the reaction between methanol and formaldehyde. The first top stream is separated into a second bottom stream and a second top stream. The second bottom stream includes poly(dimethoxymethane) while the second top stream includes dimethoxymethane, methanol, and ethanol. The second top stream is separated into a third bottom stream and a third top stream. Third bottom stream includes methanol and ethanol while the third top stream includes dimethoxymethane. The third top steam can be recycled to form additional poly(dimethoxymethane). A system that implements the method is also provided.

A fuel composition for use in internal-combustion engines has a fuel component, an alcohol component, a water component, a microemulsion blend, and a cetane-enhancer component. The microemulsion blend includes at least one of lower grade fatty acid derivatives being present in an amount effective for the fuel, alcohol, and water components to form a microemulsion blend. The emulsifier is present in an amount effective for the biodiesel fuel, alcohol, water, and emulsifier to form an emulsion.

A fuel for an internal combustion engine includes a fatty alkyl ether having a formula corresponding to formula (II): ##STR00001##
wherein x is 1-8, and y is 0 to 3; and the alkyl is an alkyl group having a number of carbon atoms that is less than the number of carbon atoms in the alkyl chain on the opposite side of the oxygen atom. The fatty alky ether can be used as a neat fuel or blend with biodiesel, diesel, ethanol or other fuels. The fatty alkyl ethers are improved in cetane number and cold flow properties over a biodiesel with fatty acid methyl acid methyl ester compounds. This is particularly valuable for compression ignition engines. A method of combustion in several types of engines is also disclosed.

The invention relates to a process for recovering sterols and a fraction rich in fatty acids and resin acids from tall oil pitch, said process comprising a) saponifying the tall oil pitch with an alkali to hydrolyse esters included in the pitch to free alcohols and organic acids in salt form, b) acidulating the saponified pitch with a mineral acid to convert the organic acids in salt form into free organic acids and to form an organic phase and an aqueous phase; wherein mineral acid is provided in an amount to produce an aqueous phase with a pH value of at most 3.8, c) separating the aqueous phase with a pH value of at most 3.8 from the organic phase, d) evaporation fractionating the organic phase in a thin film evaporator to obtain a distillate rich in fatty acids and resin acids and a bottom fraction rich in sterols, e) evaporation fractionating the bottom fraction to obtain a distillate rich in sterols, and f) subjecting the sterols in the sterol-rich distillate to crystallisation purification, wherein the process excludes a step of adding alkali between step c) and step d).

The invention discloses novel diesel fuel compositions including a renewable paraffinic diesel component, a fossil diesel component and an oxygenate component, as well as methods for manufacture and use of a combination of a renewable paraffinic diesel component, and an oxygenate component for reducing NOx emissions.

The invention relates to a process for recovering sterols and a fraction rich in fatty acids and resin acids from tall oil pitch, said process comprising a) saponifying the tall oil pitch with an alkali to hydrolyse esters included in the pitch to free alcohols and organic acids in salt form, b) acidulating the saponified pitch with a mineral acid to convert the organic acids in salt form into free organic acids and to form an organic phase and an aqueous phase; wherein mineral acid is provided in an amount to produce an aqueous phase with a pH value of at most 3.8, c) separating the aqueous phase with a pH value of at most 3.8 from the organic phase, d) evaporation fractionating the organic phase in a thin film evaporator to obtain a distillate rich in fatty acids and resin acids and a bottom fraction rich in sterols, e) evaporation fractionating the bottom fraction to obtain a distillate rich in sterols, and f) subjecting the sterols in the sterol-rich distillate to crystallisation purification, wherein the process excludes a step of adding alkali between step c) and step d).