US 4,303,494 A · Continuous reaction/separation method for nucleated growth reactions

Abstract

A solid product resulting from the nucleated growth of the product on solid material of either the same or different composition and having a density higher than the reaction medium is formed from one or more liquid phase reactants by a method which comprises tangentially introducing the liquid phase reaction medium into the lower, smaller end of an inverted, frusto-conical reactor-separator, thereby imparting an upward swirling motion to the reaction medium in the reactor-separator, the horizontal velocity at the bottom of the reactor-separator being sufficiently large to cause fluidization of larger, solid product particles and concentration of them in the central lower portion of the reactor-separator and the vertical velocity at the top of the reactor-separator being sufficiently small to avoid carry-over of the smaller solid particles but sufficiently large to concentrate them in the upper portion of the reactor-separator; at least periodically recovering the larger, solid product particles in spherical form from the bottom of the reactor-separator; and recovering fluid products from the top of the reactor-separator. The method described is useful in a variety of reactions wherein a solid product forms by a nucleated growth mechanism. Examples of such reactions include thermal upgrading of petroleum derived feedstocks and coal liquids, synthesis of zeolites and Ziegler-Natta polymerization of olefins.

Claims34

Dependent claims

An improved method for thermally upgrading coal liquids to form lower boiling hydrocarbons and coke which method comprises:

(a) tangentially introducing a coal liquid into the lower, smaller end of an elongated, vertical reaction zone of circular cross-section wherein the circular cross-sectional area generally decreases from top to bottom, thereby imparting an upward, swirling motion to the coal liquid in the reaction zone, the horizontal velocity at the bottom of the reaction zone being sufficiently large to cause fluidization of larger coke particles formed by nucleated growth in the reaction zone and concentration of them in the central, lower portion of the reaction zone and the vertical velocity at the top of the reaction zone being sufficiently small to avoid carry-over of smaller coke particles but sufficiently large to concentrate them in the upper portion of the reaction zone;
(b) maintaining the coal liquids in the reaction zone in a swirling, fluidized state at a temperature within the range from about 800.degree. to 1100.degree. F., a pressure of about 100 to 2500 psi, and for a residence time within the range from about 10 min. to 2 hours;
(c) at least periodically recovering the larger coke particles in substantially spherical form from the bottom of the reaction zone;
and
(d) recovering substantially solids-free lower boiling hydrocarbons from the top of the reaction zone.

2 more elements

An improved method for liquefying and converting solid carbonaceous material to lower boiling hydrocarbons and coke-like particles which comprises:

(a) heating carbonaceous material in the presence of coal liquefaction solvent selected from the group consisting of makeup solvent, recycle solvent, and mixtures thereof to a temperature within the range from about 600.degree. to 1100.degree. F.;
(b) tangentially introducing the heated mixture into the lower, smaller end of an elongated, vertical reaction zone of circular cross-section wherein the cross-sectional area generally decreases from top to bottom, thereby imparting an upward, swirling motion to the heated mixture in the reaction zone, the horizontal velocity at the bottom of the reaction zone being sufficiently large to cause fluidization of larger coke-like particles formed by nucleated growth in the reaction zone and concentration of them in the central, lower portion of the reaction zone and the vertical velocity at the top of the reaction zone being sufficiently small to avoid carry-over of smaller coke-like particles formed and/or present in the reaction zone but sufficiently large to concentrate them in the upper portion of the reaction zone;
(c) maintaining the heated carbonaceous material/solvent mixture in the reaction zone for a residence time within the range from about 5 minutes to 10 hours;
(d) withdrawing substantially solids-free liquid from the top of the reaction zone;
(e) recovering larger, coke-like particles as a slurry from the bottom of the reaction zone;
and
(f) separating the slurry to recover fluid and solid products.

4 more elements

Dependencies are inferred from the claim text.

Continuous reaction/separation method for nucleated growth reactions

Life of this patent

Continuous reaction/separation method for nucleated growth reactions

Life of this patent

Abstract

Claims34