Methods and Systems for Capturing and Storing Carbon Dioxide

Abstract

Methods and systems for capturing and storing carbon dioxide are disclosed. In some embodiments, the methods include the following: mixing materials including magnesium or calcium with one or more acids and chelating agents to form a magnesium or calcium-rich solvent; using the organic acids derived from biogenic wastes as acids or chelating agents; generating carbonate ions by reacting a gas including carbon dioxide with a carbonic anhydrase biocatalyst; reacting the solvent with the carbonate ions to form magnesium or calcium carbonates; recycling a solution containing the biocatalyst after forming magnesium or calcium carbonates for re-use in the generating step; using the magnesium and calcium carbonates as carbon neutral filler materials and using the silica product as green filler materials or inexpensive absorbents.

What is claimed is: 
     
         1 . A method of capturing and storing carbon dioxide, said method comprising:
 mixing materials including magnesium or calcium with at least one of one or more acids and chelating agents to form a magnesium or calcium-rich solvent;   generating carbonate ions by reacting a gas including carbon dioxide with a biocatalyst; and   reacting said solvent with said carbonate ions to form magnesium or calcium carbonates.   
     
     
         2 . The method according to  claim 1 , further comprising:
 recycling a solution containing said biocatalyst after forming said magnesium or calcium carbonates for re-use in said generating step.   
     
     
         3 . The method according to  claim 1 , wherein said biocatalyst is a carbonic anhydrase. 
     
     
         4 . The method according to  claim 3 , wherein said carbonic anhydrase is one of the enzymes Cam or Cab. 
     
     
         5 . The method according to  claim 3 , wherein said carbonic anhydrase is a whole cell that expresses one of the enzymes Cam or Cab. 
     
     
         6 . The method according to  claim 1 , wherein said magnesium or calcium materials include at least one of magnesium or calcium bearing minerals and industrial wastes. 
     
     
         7 . The method according to  claim 1 , wherein said magnesium or calcium carbonates are formed so as to mimic a particular structure of calcium carbonate. 
     
     
         8 . The method according to  claim 1 , wherein said silica product is formed so as to mimic a particular structure of precipitated silica or fume silica. 
     
     
         9 . The method according to  claim 1 , wherein said one or more chelating agents in acidic form include at least one of ethylenediaminetetraacetic acid (EDTA), acetic acid, ascorbic acid, (ortho) phosphoric acid, oxalic acid, citric acid, succinic acid, valeric acid, glutamic acid, gluconic acid, IDA, and NTA for magnesium and calcium leaching, and one or more chelating agents including catechol, guanidine, imidazole, histidine, and arginine targeting silica layer, and a combination thereof. 
     
     
         10 . The method according to  claim 9 , wherein at least one of said one or more acids and chelating agents is produced from biogenic wastes. 
     
     
         11 . The method according to  claim 1 , wherein a pH in said reactor is from about 7.5 to about 10. 
     
     
         12 . The method according to  claim 1 , wherein a solid silica material having surface area greater than 200 m 2 /g remains after magnesium is extracted from said minerals to form said solvent. 
     
     
         13 . The method according to  claim 1 , wherein said gas is one of a syngas produced from the gasification of carboneous fuel, a flue gas produced from combusting a carbonaceous fuel, a gas stream from steel manufacturing process, and a combination thereof. 
     
     
         14 . A system for capturing and storing carbon dioxide, said system comprising:
 a dissolution reactor for mixing materials including magnesium or calcium with at least one of one or more acids and one or more catalysts to form a magnesium or calcium-rich solvent;   a combined biocatalyst and carbonation reactor in fluid communication with said dissolution reactor for reacting a gas including carbon dioxide with a biocatalyst to form carbonate ions and for reacting said carbonate ions with said magnesium or calcium-rich solvent to form magnesium or calcium carbonates;   a liquid-solid separator to produce silica product;   a heat source in fluid communication with said dissolution reactor, said heat source being configured to heat said dissolution reactor thereby increasing a temperature inside said dissolution reactor; and   a control module for controlling said heat source.   
     
     
         15 . The system according to  claim 14 , further comprising:
 a biocatalyst recycle module in fluid communication with said combined biocatalyst and carbonation reactor for recycling a solution containing said biocatalyst after forming magnesium or calcium carbonates in said combined biocatalyst and carbonation reactor for re-use in said combined biocatalyst and carbonation reactor.   
     
     
         16 . The system according to  claim 14 , further comprising:
 a carbonate ion recycle module in fluid communication with said combined biocatalyst and carbonation reactor for recycling a solution containing said biocatalysts after forming magnesium or calcium carbonates in said combined biocatalyst and carbonation reactor for re-use in said combined biocatalyst and carbonation reactor.   
     
     
         17 . The system according to  claim 14 , wherein said biocatalyst is a carbonic anhydrase in the form of one of the enzymes Cam or Cab or in the form of a whole cell that expresses one of the enzymes Cam or Cab. 
     
     
         18 . The system according to  claim 14 , wherein said one or more acids and chelating agents in acidic forms include at least one of ethylenediaminetetraacetic acid (EDTA), acetic acid, ascorbic acid, (ortho) phosphoric acid, oxalic acid, citric acid, succinic acid, valeric acid, glutamic acid, gluconic acid, IDA, and NTA for magnesium and calcium leaching, and one or more chelating agents including catechol, guanidine, imidazole, histidine, and arginine targeting silica layer, and a combination thereof. 
     
     
         19 . The system according to  claim 14 , further comprising:
 a pH control module in fluid communication with said combined biocatalyst and carbonation reactor, said pH control module including a supply of basic material for increasing pH in said combined biocatalyst and carbonation reactor.   
     
     
         20 . A method of capturing and storing carbon dioxide, said method comprising:
 mixing materials including magnesium or calcium with one or more acids to form a magnesium or calcium-rich solvent;   generating carbonate ions by reacting a gas including carbon dioxide with a carbonic anhydrase biocatalyst;   reacting said solvent with said carbonate ions to form magnesium or calcium carbonates; and   recycling a solution containing said biocatalyst after forming magnesium or calcium carbonates for re-use in said generating step;   wherein said carbonic anhydrase biocatalyst is one of the enzymes Cam or Cab or a whole cell that expresses one of the enzymes Cam or Cab.