Agglomerated Hemicellulose Compositions, Methods of Preparation Thereof, and Processes for Enriching a Desired Mineral from an Ore

Abstract

Methods for preparing agglomerated hemicellulose compositions are provided. Agglomerated hemicellulose compositions comprising agglomerates are also provided herein. Also disclosed are processes for enriching a desired mineral from an ore comprising the desired mineral, wherein the process comprises carrying out a flotation process in the presence of one or more collecting agents and a depressant composition comprising an agglomerated hemicellulose composition.

We claim: 
     
         1 . An agglomerated hemicellulose composition comprising agglomerates, wherein at least about 50% of the agglomerates are retained on a 20 mesh sieve, at least about 90% of the agglomerates are retained on a 100 mesh sieve, and the size of the agglomerates ranges from about 0.1 to about 15 mm. 
     
     
         2 . The agglomerated hemicellulose composition of  claim 1 , wherein the agglomerated hemicellulose composition is prepared by a method comprising:
 (a) providing new or undigested plant material comprising hemicellulose;   (b) combining new or undigested plant material comprising hemicellulose with a granulation fluid comprising a solvent, a caustic agent, and optionally an oxidizing agent and/or sequestering agent; and   (c) agglomerating the new or undigested plant material comprising hemicellulose with the granulation fluid to form an agglomerated hemicellulose composition comprising agglomerates;   
       wherein step (b) occurs before or simultaneously with step (c). 
     
     
         3 . The agglomerated hemicellulose composition of  claim 2 , wherein step (c) comprises (i) agglomerating the new or undigested plant material comprising hemicellulose with the granulation fluid to provide a wet agglomerated hemicellulose composition and (ii) heating the wet agglomerated hemicellulose composition to provide the agglomerated hemicellulose composition. 
     
     
         4 . A method for preparing an agglomerated hemicellulose composition or a depressant composition, comprising:
 (a) providing new or undigested plant material comprising hemicellulose;   (b) combining new or undigested plant material comprising hemicellulose with a granulation fluid comprising a solvent, a caustic agent, and optionally an oxidizing agent and/or sequestering agent; and   (c) agglomerating the new or undigested plant material comprising hemicellulose with the granulation fluid to form an agglomerated hemicellulose composition comprising agglomerates;   
       wherein step (b) occurs before or simultaneously with step (c). 
     
     
         5 . The method of  claim 4 , wherein step (c) comprises (i) agglomerating the new or undigested plant material comprising hemicellulose with the granulation fluid to provide a wet agglomerated hemicellulose composition and (ii) heating the wet agglomerated hemicellulose composition to provide the agglomerated hemicellulose composition. 
     
     
         6 . The method of  claim 5 , wherein the water content of the wet agglomerated hemicellulose composition is from about 65% to about 90% by weight. 
     
     
         7 . The method of  claim 4 , wherein the granulation fluid comprises water and a caustic agent selected from sodium hydroxide, calcium hydroxide, potassium hydroxide, lithium hydroxide, rubidium hydroxide, cesium hydroxide, magnesium hydroxide, strontium hydroxide, barium hydroxide, calcium hydroxide, a hydrate thereof, an oxide thereof, or a combination thereof. 
     
     
         8 . The method of  claim 4 , wherein the new or undigested plant material comprising hemicellulose and the granulation fluid are pre-mixed prior to agglomeration. 
     
     
         9 . The method of  claim 4 , wherein agglomeration is achieved by wet granulation. 
     
     
         10 . The method of  claim 9 , wherein wet granulation is conducted in a mixer, high-shear mixer, fluid-bed granulator or rotary granulator. 
     
     
         11 . The method of  claim 4 , wherein agglomeration is achieved by pelletization. 
     
     
         12 . The method of  claim 11 , wherein pelletization is achieved by extrusion-spheronization or tumble-growth agglomeration. 
     
     
         13 . The method of  claim 12 , wherein tumble-growth agglomeration is conducted in a disc pelletizer or rotary drum. 
     
     
         14 . The method of  claim 4 , wherein at least about 50% of the agglomerates are retained on a 20 mesh sieve.