Choline hydroxide for salt displacement in renewable feedstock process

Abstract

The disclosure relates to displacing corrosive salts in processing or co-processing renewable feedstocks. More specifically, the disclosure relates to displacing corrosive salts through the addition of choline-based hydroxides in the affected section of process unit that experience high levels of ammonia, amines, or chlorides and their use for reducing salt fouling and corrosion.

What is claimed is: 
     
         1 . A method for inhibiting fouling or corrosion of a surface in contact with a renewable process fluid comprising contacting a salt dispersant agent with a corrosion salt, wherein a process for refining a renewable feedstock comprises the renewable process fluid and the salt dispersant agent reacts with the corrosion salt to produce an aqueous-soluble dispersant salt. 
     
     
         2 . The method of  claim 1 , wherein the salt dispersant agent comprises an organic amine. 
     
     
         3 . The method of  claim 1 or 2 , wherein the salt dispersant agent comprises a quaternary trialkylalkanolamine. 
     
     
         4 . The method of any one of  claims 1 to 3 , wherein the salt dispersant agent comprises a quaternary tri(C 1 -C 6  alkyl)C 1 -C 6  alkanolamine. 
     
     
         5 . The method of  claim 4 , wherein the salt dispersant agent comprises a quaternary trimethyl alkanolamine. 
     
     
         6 . The method of  claim 5 , wherein the salt dispersant agent comprises trimethyl ethanolamine hydroxide (choline hydroxide). 
     
     
         7 . The method of  claim 5 , wherein the salt dispersant agent comprises trimethyl iso-propanolamine hydroxide (β-methyl choline hydroxide). 
     
     
         8 . The method of any one of  claims 3 to 7 , wherein the quaternary trialkylalkanolamine is stabilized. 
     
     
         9 . The method of  claim 8 , wherein the quaternary trialkylalkanolamine is stabilized with an alkanolamine. 
     
     
         10 . The method of  claim 8 , wherein the quaternary trialkylalkanolamine is stabilized with a diamine. 
     
     
         11 . The method of any one of  claims 1 to 10 , wherein the salt dispersant agent has a concentration from about 1 to about 5000 ppm in the renewable process fluid. 
     
     
         12 . The method of any one of  claims 1 to 11 , wherein the salt dispersant agent contacts the corrosion salt by injecting the salt dispersant agent into the renewable process fluid. 
     
     
         13 . The method of any one of  claims 1 to 12 , wherein the renewable process fluid comprises ammonium, amine, and chloride ions. 
     
     
         14 . The method of any one of  claims 1 to 12 , wherein the corrosion salt comprises chloride. 
     
     
         15 . The method of any one of  claims 1 to 12 , wherein the corrosion salt comprises ammonium. 
     
     
         16 . The method of any one of  claims 1 to 12 , wherein the corrosion salt comprises ammonium chloride. 
     
     
         17 . The method of any one of  claims 1 to 12 , wherein the corrosion salt comprises amine-hydrochloride salt. 
     
     
         18 . The method of any one of  claims 1 to 17 , wherein the aqueous-soluble dispersant salt is a quaternary trialkyl alkanolamine chloride. 
     
     
         19 . The method of  claim 18 , wherein the aqueous-soluble dispersant salt comprises trimethyl ethanolamine chloride (choline chloride). 
     
     
         20 . The method of  claim 18 , wherein the aqueous-soluble dispersant salt comprises trimethyl iso-propanolamine chloride (β-methyl choline chloride). 
     
     
         21 . The method of any one of  claims 1 to 20 , wherein the aqueous-soluble dispersant salt has a higher water solubility than the corrosion salt. 
     
     
         22 . The method of any one of  claims 1 to 21 , wherein the aqueous-soluble dispersant salt has a water solubility of at least about 0.2 mole aqueous-soluble dispersant salt per mole water at a temperature of 0° C. 
     
     
         23 . The method of any one of  claims 1 to 21 , wherein the aqueous-soluble dispersant salt has a water solubility of at least about 0.3 mole aqueous-soluble dispersant salt per mole water at a temperature of 0° C. 
     
     
         24 . The method of any one of  claims 1 to 21 , wherein the aqueous-soluble dispersant salt has a water solubility of at least about 0.4 mole aqueous-soluble dispersant salt per mole water at a temperature of 0° C. 
     
     
         25 . The method of any one of  claims 1 to 24 , wherein the aqueous-soluble dispersant salt has a water solubility of up to about 1.4 mole aqueous-soluble dispersant salt per mole water at a temperature of 0° C. 
     
     
         26 . The method of any one of  claims 1 to 25 , wherein the corrosion salt is formed in the renewable process fluid during refining of the renewable feedstock. 
     
     
         27 . The method of any one of  claims 1 to 26 , wherein the renewable feedstock comprises soybean oil, palm oil, corn oil, waste oil, an animal fat, biomass waste, recycled carbon, a sugar, a starch crop, or a combination thereof. 
     
     
         28 . The method of any one of  claims 1 to 27 , wherein the aqueous-soluble dispersant salt dissolves in an aqueous phase of the renewable process fluid. 
     
     
         29 . The method of any one of  claims 1 to 28 , wherein the surface is a metal surface in a piece of equipment in the process for refining the renewable feedstock. 
     
     
         30 . A method for inhibiting fouling or corrosion of a surface in a piece of equipment in a process for refining a renewable feedstock, the method comprises contacting a salt dispersant agent with a corrosion salt produced in the process for refining the renewable feedstock, wherein the salt dispersant agent comprises choline hydroxide or β-methyl choline hydroxide, and the corrosion salt comprises ammonium chloride, an alkyl ammonium chloride, an aryl ammonium chloride, an alkyl-aryl ammonium chloride, or a combination thereof, whereby choline chloride or β-methyl choline chloride is formed.