A composition of fuel additives includes at least a first additive having a partial ester derivative of polyols and a second additive having a quaternary ammonium salt. The first additive includes at least 50% by mass of a compound A selected from the partial esters of polyols and saturated or unsaturated, linear or branched, cyclic or acyclic C.sub.4 to C.sub.36 monocarboxylic aliphatic hydrocarbarbons, the partial esters being able to be used alone or in a mixture. The disclosure also relates to a diesel fuel including such a composition and the use of the fuel for limiting the deposits in a diesel engine. In particular, the disclosure relates to the use of the fuel containing the composition of additives of the present disclosure in direct-injection diesel engines.

The disclosure encompassed herein relates, in part, to a method for increasing energy density of plant biomass that can be used for production of renewable fuel, such as biodiesel oil and/or ethanol. In an aspect, genetic engineering for enhanced sugar accumulation can be achieved by overexpressing a bacterial enzyme sucrose isomerase. Sugars or oils extracted from the plants of the disclosure encompassed herein may be used for industrial purposes such as heating, producing bio-fuels such as biodiesel fuel, or lubricating applications.

A method for production of a biodiesel is described herein. The method for production of a biodiesel comprises (a) separating solids from a waste oil composition to provide a clarified oil composition; (b) acidifying the clarified oil composition to produce an acidified oil composition including free fatty acids derived from the waste oil; (c) converting at least a portion of the free fatty acids in the acidified oil composition to glycerides to provide a glyceride composition; and (d) reacting at least a portion of the glycerides in the glyceride composition with methanol to form fatty acid methyl ester to provide a biodiesel composition.

There is described a process and an apparatus for purifying a mixture and related products. In particular, there is described a process and an apparatus for purifying a mixture comprising fats, oils and greases as are typically found in sewer waste. The process involves heating, acidifying and separating the mixture. The apparatus used includes a heating and separation device for separating into a solid fraction, an organic liquid fraction and an aqueous liquid fraction. Apparatus such as a three phase separation unit and a rotary vacuum filter may also be used.

A process for production of biofuels from algae can include cultivating an oil-producing algae by promoting sequential photoautotrophic and heterotrophic growth. The method can further include producing oil by heterotrophic growth of algae wherein the heterotrophic algae growth is achieved by introducing a sugar feed to the oil-producing algae. An algal oil can be extracted from the oil-producing algae, and can be converted to form biodiesel.

The invention discloses a method for producing bio-fuel (BF) from a high-viscosity biomass using thermo-chemical conversion of the biomass in a production line (10) with pumping means (PM), heating means (HM) and cooling means (CM). The method has the steps of 1) operating the pumping means, the heating means and the cooling means so that the production line is under supercritical fluid conditions (SCF) to induce biomass conversion in a conversion zone (CZ) within the production line, and 2) operating the pumping means so that at least part of the production line is in an oscillatory flow (OF) mode. The invention is advantageous for providing an improved method for producing biofuel from a high-viscosity biomass. This is performed by an advantageous combination of two operating modes: supercritical fluid (SCF) conditions and oscillatory flow (OF).

The present invention provides a method for producing a biofuel that allows an animal/vegetable fat/oil raw material containing a free fatty acid to react with a lower alcohol in the presence of a solid acid catalyst, in which the consumption of the lower alcohol is reduced and the free fatty acid and the lower alcohol are selectively esterified to reform the animal/vegetable fat/oil. In this method, as a solid acid catalyst is used a catalyst selected from an SiO.sub.2/Al.sub.2O.sub.3 solid acid catalyst, an SiO.sub.2/Al.sub.2O.sub.3 solid acid catalyst with aluminum being partially introduced into mesoporous silica, an Al.sub.2O.sub.3/B.sub.2O.sub.3 solid acid catalyst, and a sulfated zirconia solid acid catalyst, with a molar ratio of the free fatty acid and the lower alcohol of 1 to 6.

The present invention concerns a method for carrying out the combined operation of a bioethanol production unit and a biogas unit. The method comprises the following steps: a) mashing corn meal from a dry milling step with at least 0.1 t of dry matter in the form of whole stillage and at least 0.1 m.sup.3 of outflow from the biogas unit per tonne of corn meal, b) feeding the mash from a) to a cooking stage with mash temperatures below the gelatinization temperature of the starch inn the corn meal, followed by an ethanol-forming fermentation step and then feeding the fermented mash to a distillation step, c) feeding the whole stillage from b) to the mashing step in a) and to the biogas unit.

Haze may be removed from a biofuel or biofuel intermediate by using a clarifier. The clarifier includes copolymer prepared using a formulation comprising an alpha olefin and maleic anhydride. The clarifier may also be used with admixtures of biofuels, biofuel intermediates, or biofuel feedstocks with conventional hydrocarbons.

A system and method for the conversion of free fatty acids to glycerides and the subsequent conversion of glycerides to glycerin and biodiesel includes the transesterification of a glyceride stream with an alcohol. The fatty acid alkyl esters are separated from the glycerin to produce a first liquid phase containing a fatty acid alkyl ester rich (concentrated) stream and a second liquid phase containing a glycerin rich (concentrated) stream. The fatty acid alkyl ester rich stream is then subjected to distillation, preferably reactive distillation, wherein the stream undergoes both physical separation and chemical reaction. The fatty acid alkyl ester rich stream is then purified to produce a purified biodiesel product and a glyceride rich residue stream. The glycerin rich second liquid phase stream may further be purified to produce a purified glycerin product and a (second) wet alcohol stream. Neutralization of the alkaline stream, formed during the alkali-catalyzed transesterification process, may proceed by the addition of a mineral or an organic acid.