Abstract: The invention concerns a two-stage process for the manufacture of a colloid of iron oxide, and results in the dispersion of the desired iron oxide particles within a carrier fluid by a mixture of mono- and polycarboxylic acids providing excellent properties to the colloid. The process also has the advantage of preserving the physical form of the iron oxide particles, allowing any desired properties of the iron oxide core (such as crystal form or magnetism) to be maintained within the colloid.

Abstract: The invention concerns a two-stage process for the manufacture of a colloid of iron oxide, and results in the dispersion of the desired iron oxide particles within a carrier fluid by a mixture of mono- and polycarboxylic acids providing excellent properties to the colloid. The process also has the advantage of preserving the physical form of the iron oxide particles, allowing any desired properties of the iron oxide core (such as crystal form or magnetism) to be maintained within the colloid.

Abstract: A method of substantially removing, or reducing the occurrence of, injector deposits in a diesel engine operated using a diesel fuel containing a minor amount of a metal-containing species is disclosed. The method includes adding to a diesel fuel the reaction product between a hydrocarbyl-substituted succinic acid or anhydride and hydrazine. The diesel engine is equipped with fuel injectors having a plurality of spray-holes, each spray-hole having an inlet and an outlet, and the fuel injectors have one or more of the following characteristics: (i) spray-holes which are tapered such that the inlet diameter of the spray-holes is greater than the outlet diameter; (ii) spray-holes having an outlet diameter of 0.10 mm or less; (iii) spray-holes where an inner edge of the inlet is rounded; (iv) 6 or more spray-holes; (v) an operating tip temperature in excess of 250° C.

Abstract: There is provided a method for flocculating one or more particulate materials present in a dispersion, the method comprising contacting the dispersion with (i) fibrous cationic colloidal alumina microparticles; and (ii) a cationic polymer and/or a non-ionic polymer.