Methods and Apparatus for Removal of Degradation Byproducts and Contaminants from Oil for Use in Preparation of Biodiesel

Abstract

Methods, particles, and devices are disclosed for filtration of oil for use of the oil in the preparation of biodiesel. Disclosed particles may comprise a substantially inert porous particle with a coating comprising a polymer having amine, amino, and/or imine group(s).

What is claimed: 
     
         1 . A particle suitable for filtration of oils for use in preparation of biodiesel, said particle comprising a substantially inert porous inner particle and at least a partial coating on said inner particle, wherein said coating comprises a non-food grade acceptable polymer comprising an amine group, an imine group, or both. 
     
     
         2 . The particle of  claim 1 , wherein said polymer comprises a primary amine group. 
     
     
         3 . The particle of  claim 1 , wherein said polymer comprises a secondary amine group. 
     
     
         4 . The particle of  claim 1 , wherein said polymer comprises a positively charged amine group, a positively charged imine group, or both. 
     
     
         5 . The particle of  claim 4 , wherein said coating comprises an amine salt. 
     
     
         6 . The particle of  claim 1 , wherein said non-food grade acceptable polymer comprises at least one of the following: allylamine, polyvinylamine, and branched poly(ethylene)imine. 
     
     
         7 . The particle of  claim 1 , wherein said polymer is cross-linked so that said coating is substantially porous. 
     
     
         8 . The particle of  claim 1 , wherein said coating has a thickness of about 1 micron or less. 
     
     
         9 . The particle of  claim 1 , wherein said substantially inert porous inner particle comprises at least one of the following: diatomaceous earth, kaolin, silica, and siliceous clay. 
     
     
         10 . The particle of  claim 9 , wherein said substantially inert porous inner particle comprises diatomaceous earth. 
     
     
         11 . The particle of  claim 1 , further comprising a silane coupling moiety. 
     
     
         12 . The particle of  claim 11 , wherein said coating comprises branched poly(ethylene)imine linked to said inner particle via said silane coupling moiety. 
     
     
         13 . The particle of  claim 1 , having a diameter from about 1 to about 10 microns. 
     
     
         14 . A method for removing contaminants from used oil, the method comprising the step of contacting the oil with a filtering media, wherein the filtering media comprises a non-food grade acceptable polymer comprising an amine group, an imine group, or both, thereby removing at least some of said contaminants and making said oil suitable for use in preparation of biodiesel. 
     
     
         15 . The method of  claim 14 , wherein said polymer comprises a primary amine group. 
     
     
         16 . The method of  claim 14 , wherein said polymer comprises a secondary amine group. 
     
     
         17 . The method of  claim 14 , wherein said polymer comprises a positively charged amine group, a positively charged imine group, or both. 
     
     
         18 . The method of  claim 14 , wherein said polymer comprises an amine salt. 
     
     
         19 . The method of  claim 14 , wherein said filtering media comprises a plurality of particles. 
     
     
         20 . The method of  claim 19 , wherein said particles are at least partially coated with said polymer. 
     
     
         21 . The method of  claim 19 , wherein said particles have an average diameter of from about 1 to about 10 microns. 
     
     
         22 . The method of  claim 17 , further comprising the step of contacting said polymer with an acid, thereby creating said positive charge. 
     
     
         23 . The method of  claim 22 , wherein said acid comprises hydrochloric acid. 
     
     
         24 . The method of  claim 17 , wherein said polymer is in the form of a hydrochloric acid salt. 
     
     
         25 . The method of  claim 14 , wherein said polymer is cross-linked. 
     
     
         26 . The method of  claim 20 , wherein said inner porous particles comprise diatomaceous earth. 
     
     
         27 . The method of  claim 26 , wherein said coating comprises branched poly(ethylene)imine. 
     
     
         28 . The method of  claim 27 , wherein said coating is covalently bonded to said particle via a coupling moiety. 
     
     
         29 . The method of  claim 28 , wherein said coupling moiety is a silane moiety. 
     
     
         30 . The method of  claim 14 , wherein said contaminants comprise fatty acids. 
     
     
         31 . The method of  claim 30 , wherein after said contacting, said polymer forms a fatty-acid electrostatic complex and the method further comprises the step of removing the charge on the amine group to remove said fatty acid from said polymer, wherein said polymer is then capable of again removing contaminants. 
     
     
         32 . The method of  claim 30 , wherein said removing step comprises at least one of the following:
 (i) changing the pH of said complex; and   (ii) exposing said complex to a salt solution.   
     
     
         33 . A filtration device comprising the particle of  claim 1 . 
     
     
         34 . A particle comprising an inner porous core of diatomaceous earth and at least a partial coating covalently bound via a silane moiety to said porous core. 
     
     
         35 . The particle of  claim 1 , wherein said particle is suitable for filtration of used edible oils for use of said oils in preparation of biodiesel. 
     
     
         36 . The method of  claim 14 , wherein said method removes contaminants from used edible oil. 
     
     
         37 . The particle of  claim 1 , wherein said polymer comprises a tertiary amine group.