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This proposal was moved to: Transportation Workspace 2021
This proposal was reopened in Transportation 2015


Simple CO2 filter feasible today, fits all transport motor vehicles, potential high for CO2 capture at low cost, safe storage with benefits



The CO2 imperative is economic capture and safe storage today.  An example is vehicle’s exhaust CO2 reduced by filtering at low cost.    

Previously, formulas with faster kinetics captured 40% CO2/volume output over 50 miles. [1]  

New formulas in this report, capture CO2 by media weight increase over mileage. The weight gains reported are modest 1% to 50% over 100 to 1000 miles.  

The 50% case increase, post 1000 miles, is from a fused media of double salt-silicate matrix in a porous/friable state, forming an intractable mass after the long exhaust dwell-time of 1000 miles.  

If the case were duplicated on fleet vehicles driven 24/7/365, the CO2 separated from exhaust amount over one year could be a significant one million tons CO2.

Assumptions: the same filter on 100,000 fleet vehicles, same mineral media weight-gain each 1000 miles total annual gain = 876,000 tons CO2.

Formulated media of cation/silicate composition derived from low cost mineral waste dust from stone cutting processes and remixed.  Composition of dust samples compose spherical beaded media of 1-mm sized particles which react to vaporous CO2+H2O acidic exhaust capturing

Mold-making a filter could enable machine-stamped filter parts mass-produced. Duplicated initial results on many vehicles would amount to multiples of above case results to significant amounts for filters costing $10 each with a mineral dust per ton of $30.

There were no interruptions to vehicle performance or changes in fuel consumption using this filter.

Exhaust exposed media:  mineral-CO2 solid is inert and safe to store below ground or reuse as fertilizer.  In soil it promotes biomolecular chlorophyll blooms, but not in controls.

Study contributes benchmarking exercise for mobile-sourced CO2 capture and safe storage as well as, material for further analysis necessary for low emission security.


What actions do you propose?

Vehicle CO2 reduction

Historically, catalytic converters were made mandatory on all United States vehicles to meet Federal guidelines established for allowed emissions with lower standard threshold limits on various combustion gases. [2, 3]  

Catalytic converters are not meant to treat oxides of carbon, CO or CO2.

Exhaust catalysts make use of metals like platinum and palladium to achieve required lower limits on specific exhaust gases.  They work well as designed and burn only regulated species of gases to lower their emission levels.  Low levels of those species remain after catalyst treatment, as permissible by law.

To emphasize, catalytic converters do not treat CO2. All motor vehicles freely vent CO2 - the primary greenhouse gas (GHG) responsible for global warming and climate change [ ].

Untreated CO2 with low levels of post-catalyst gases mentioned, concentrate in regular pollution plumes over most cities, packing the air with tailpipe all species:

ozone (O3) hydrocarbons (HC) sulfur oxides (SOx) nitrogen oxides (NOx) particulate matter (PM) volatile organic carbon (VOCs) carbon oxides of carbon monoxide (CO) and CO2 [4]


        SMOG over Los Angles, California.   

In United States government standards have not kept pace with airborne contamination.  No established regulations or current legislation exists mandating mechanisms to scrub tailpipe gases in-general or CO2 in-particular before entry or after tailpipe

CO2 follows the water cycle  

Atmospheric CO2 dissolves into water and forming solutions of weak carbonic acid. Thermodynamically unstable, the molecule in water changes to carbonate and bicarbonate anions. The hydrosphere water cycles between the biosphere, lithosphere and atmosphere. [5] 

Atmospheric CO2 increased in past from volcanism and mountain formation by shifting continental plates as fossil and geological records indicate.  The resulting greenhouse effect damaged life on the planet until air-CO2 concentrations diminished gradually over millions of years through long-term storage of the water-dissolved aerosol finally formed mineral carbonates. [6] 

Caged CO2 in mineral form 

Terrestrial and marine photosynthesis by organisms activate short and long-term CO2 storage.

Land plants decay.  Portions of their carbon drain to the flood plain or river deltas, returning CO2 to the atmosphere in near-term cycles. 

In contrast, marine plants like microscopic calcareous plankton, will not decay. Their microscopic shells fall from the sunlit surface into sea-floor mud forming carbonate deposits over geological time.  

Foraminifera Shell The shells of microscopic


A single 6-inch cube of chalk from the White Cliffs of Dover in Southern England contains over 1000 liters of compressed CO2 from the Cretaceous atmosphere [6, 7]

         White Cliffs of Dover

Geochemical reaction - slow CO2 capture/storage (years)

Acidic water dissolving carbonate rocks and minerals is geochemical weathering, a gradual erosion due to any amount of CO2 dissolving into water as rain falls through the air. Portions of dissolved CO2 consolidate, form weak carbonic acid and saturate the landscape. 

With more CO2 in the air, more hydrated carbonate ions wet terrestrial and subterranean realms, creating global acid-base reactions. One example is paragenesis resulting from common metasomatic rock alteration by hydrothermal deposits of dissolved mineral elements.

The rain containing carbonate (CO3^2-) and bicarbonate (HCO3-) ions in equilibrium is unbalanced on contact with silicate minerals of calcium, potassium, sodium, or magnesium surface or subterranean sediment. The result is either a breakdown or formation reaction because dissolved carbonate and bicarbonate in groundwater is amphiprotic, meaning a solution can function as an acid or base depending on local pH.  Groundwater pH can vary between 5.6 and 10 influencing the ion balance and silicon-carbonate solids will either breakdown or form. 

Lower pH dissolves carbonate and higher pH will reduce carbonate solubility to precipitate carbonate.

Artificial geochemical reaction - accelerated CO2 capture/storage (minutes)

By comparison, if the acidic vaporous CO2+H2O in the exhaust environment experiences a region of higher pH by metal salt exposure to the gaseous flow, the breakdown reaction is reversed.  A formation reaction precipitates carbonate in fast reactions [8] and sediment salts slowly by comparison fuse solid by a gradual gathering of the attractive and continuously available negative bicarbonate ions in acidic fumes of partial amounts  abundant CO2 dissolved-in-water vapors.

   Nature's CO2 storage (interactive slides, NG) 

A natural analog to the vehicle CO2 trap is a cave environment. Groundwater with dissolved Ca2^+  CO3^2-  HCO3-   H2CO3 is carried by gravity to cave ceiling and drips calcium ions acquired by progressing through the overburden. Results are formations or long-term removal of CO2 from water column's vertically distributed saturation by stalactite and stalagmite precipitates growing yearly their 1-mm diameter expansion in a slow storage of CO2, processing from an overly abundant sum [12, 13] 

Filter reaction area

Reactor designed/installed/leak-tested with a cylinder insert [10] for positioning downstream from catalytic converter in a lower temperature region of fluid flow.  The insert enables exhaust to penetrate a triple-wall of mesh containing filter media and water reservoir both in a 1-liter internal volume and removable by thumb screws for maintenance.

Developing reaction material

Elements Ca, K, Mg, Na of Group I and II employed in combination with trace transition metals and non-metals of inexpensive rock-content easily obtainable.

In nature binary oxides of the above elements like calcium and magnesium are rare and the carbonation reactions are strongly exothermic, so none were determined unusable.

More (Yegulalp et al. 2000)  with details: [18]

... carbonation reaction shown by simple reaction of binary oxides, MgO and CaO. These reactions are exothermic. 

CaO + CO2 = CaCO3 + 179 kJ/mole MgO + CO2 = MgCO3 + 118 kJ/mole

Even compared to heat released in the combustion of carbon (394 kJ/mole), substantial heat is created.

Calcium and magnesium silicates are common in nature and are determined useful. Magnesite, forsterite and serpentine among others have carbonation reactions with less heat.  

Again (Yegulalp, et al. 2000) details:  [18]

...consider the carbonation reactions of forsterite and serpentine. For forsterite and serpentine respectively:

 ½Mg2SiO4 + CO2 = MgCO3 + ½SiO2 + 95kJ/mole 1/3Mg3Si2O5(OH)4 + CO2 = MgCO3 + 2/3SiO2 + 2/3H2O + 64kJ/mole

Both reactions are favored at low temperatures. In nature magnesite and silica are common in serpentinized ultramafic rocks. Their formation is due to natural CO2–rich fluids percolating through mineral deposits. Magnesite is stable and not likely to release the bound CO2. 

Formation of mineral beads   

Aqueous alkaline-treated sand partially dried, added to mineral powders. A quantity of rock powder and sand with moisture is mixed by shaking/rolling in glass tube.

Ingredients appear coating layers on course sand grains forming spheres in concert, proportionally uniform 1-mm diameter particles, distributed throughout the volume rolling in the tube.

Material with alkaline treated sand include Kansas chalk, brucite, serpentine, dolomite, limestone trace oxides Na, K.

Exhaust CO2 control -  flow region of high pH

Exhaust contains about 14% CO2/v, 6-8% H2O /v. Supplemental H2O/v from reservoir contributes another approx. 2-3%. Temperature remains around 140 F. 

Multiple low levels CO2 captured by geochemical cation/silicate composition/vehicle exhaust process during various lengths of travel including 

       lmitied tests occurred coast-to-coast (NYC to LA), June, 2015. 

Exhaust environment H2O + CO2 appear only participants reacting with gas separation media.  After series of exposures between 100-300 miles, spherical bead diameter growth rate doubles and triples, but growth is non-uniform throughout the media volume suggesting uneven exhaust exposure. However, the same bead media exposed to 1000 miles results in uniform solids with higher mechanical strength.  

 Final solid mass appears less porous with decreased brittleness after 1000 miles than those exposed to 100-300 miles, using the same bead material.  Also, with longer exhaust flow, non-uniformity is absent with a final solid distributed throughout the material mass, suggesting the non-uniformity is an artifact lower exhaust exposure. 

CO2 capture from mobile source -  results and discussion

Theoretical calculation of combustion reactants equal total mass of products and exact mixing proportions for efficient burn of all fuel completely.  The reality of internal combustion engines is they are inefficient.  Not all fuel burns. However, air:fuel ratios commonly 14:1 means one gallon of gasoline (6 pounds) will produce about 19 pounds of CO2.

Estimated exhaust exposure of 100 miles gains about 50% over initial filter weight. Beads at end of exposure are porous solid aggregates. Exposed 1000 miles, fused aggregates with higher mechanical strength. the one-vehicle yield over mileage is modest. 

  •  1000 vehicles/1000 miles = 1 ton of CO2 in half day (hours) 
  •  100,000 vehicles/100,000 miles = 100 tons of CO2 (few minutes)


Geochemical mineral/water CO2 capture/storage is slow process.  By comparison, a derived method accomplished same task in minutes.  

Example, 100,000 vehicles driven 24/7/365 are projected to capture about a million tons of CO2 per year (876,000 tons/CO2/yr).

Greater distance traveled/carbon unit captured are realized by exploiting porosity content of mixed mineral components and quantity of CO2+H2O uptake from mobile sources.

Artificial mineral-CO2 strength - function of time in acidic flow

Natural geochemical carbon capture and safe storage with reusable capacity for soil and water organic growth-promoting agents are suggested.

The filter solids saturated with CO2 are effectively reusable as potential products for soil remediation. Experiments are showing crushed filter residue spread in layers beneath barren sandy soil inside glass tubes, when watered, and then exposed to sunlight green biotic carbon appears over time.- evidence not apparent in controls.

Cycling the mineral salts and silicate to a solid less porous state by exposure to exhaust CO2+H2O, is experimentally determined to be useful.  Safe, long-term CO2 storage as an inert solid or reuse of the CO2/mineral matrix as nutrient additives to soil or water are recommended.

Spherical formation of mineral beads   

Mineral positive salts contained appear influenced by an electric field from the tribo-electric charge on glass surface. Mineral dust re-forms into a polar matrix of semi-solid spheres, uniformly distributed and 1-mm diameter.

The synthesized mix swirled in glass with material/glass surface contact creating negative charge and electric field exposed ingredients.  The diverse positive material and the e-field assist powder coating of sand particles by natural attractive force.  Course particles of sand self-assemble coatings of dust growing in diameter to achieving a maximum 1-mm uniformity throughout the container volume by use of intrinsic electron properties on exposure to a triboelectric field.   

Further questions for lab analysis

Further research finding optimum mass gain and carbonation or oxide percentages of selected composition are important to follow-on as are the percentages of water adsorption rates relative to the solid formation during exposed millage and bead+H2O+CO2 exposure.  

Subjects are determined beyond the scope of reporting here and suitable for university laboratory analysis.

Characterizing quantified assessment moisture and carbonation percentage influencing exhaust filter material combination and kinetics, instrument analysis of the mass gain over exposure times are important to follow-on beyond scope of proposal and suitable for instruments of more qualified lab.

Who will take these actions?

Filters to collect carbon, drivers paid a percent

Vehicle owners are paid for a small percentage of the total carbon captured by filtration.  owners are offered free incentives like maintenance to continue collection efforts and payments for carbon amounts collected by retrofit filters installed.  During filter deployment, service agreements with vehicle owners are establish the filter company agrees to pay the vehicle owners a percentage of the value of the carbon collected.

Vehicle owners electronically credited for carbon collected post collection payment being proportional to amount and value of carbon yield as determined by carbon price, or point of sale products.

Products may include soil and water nutrient additives for enhanced plant/animal growth among others.

Free filters are deployed and technology service provided through clean air investors for material gain from carbon credits, carbon storage, distribution of carbon products or by-product sales, R&D, manufacturing, liciencing, and training. 


Displaying 100_7804.JPG

Where will these actions be taken?

In The USA

Lifecycle of CO2 filter  

  • Filter Housing is Stainless Steel and lasts as long as sock muffler

  • MCO2 capture media is 500 miles today

All one billion motor vehicles on road today are candidates for CO2 filters

  • Filter design scales to all standand tailpipes, small to largest

  • Small = 1 and ¼ inch Hybrid Electric vehicle

  • Large = 8-10 inch Diesel tractors and construction vehicles

 What percentage of CO2 is being removed?  

The amount of CO2 capture from exhaust is determined by measuring the filter weight before exposure and the filter weight after exposure.  The amounts removed cited here are percent of weight gain after exposure, a range 1% to 50% increase miles exposed.  _________________________________________________

How often would the units need replacing, and how much do they weigh, both new and when "full"? This is important as it impacts vehicle fuel consumption.  

Weight of filter material before exposure (n-1) after acidic vapor 1000 mile exposure (n+1) _________________________________

Would the market to buy carbon from vehicle owners saturated? If so, how soon? How many buyers are there, realistically?

All C solids can sell as fertilizer for agriculture first food Carbon Credits later.

CO2 content combined with mineral in exhaust solids, value as soil/water CO2 supplement for fish, alga, aquaculture, also mineral necessary for growth.


Would regulation be an alternative, possibly leading to faster uptake of the technology, once it is mature? 

There's no need for legislation or policy change.  Increased adoption by vehicle owners due to incentives, same as those returning bottle deposits.  They don’t own the bottles, but very popular to turn them in.

Also, it's like collecting Green Stamps from groceries, stick them in a book, save for item of equal value, collecting later.

Can't legislate a good deed for environment or Green up Day volunteer. 

How much will emissions be reduced or sequestered vs. business as usual levels?

CO2 reduction amount  (2015)

Exposed 100 miles, gain 50% over initial  = porous solid

Exposed 1000 miles fuse aggregate = higher mechanical strength. 

Vehicle CO2 yield/mileage  

1000 vehicles/1000 mi = tn CO2 in half day (hrs) 

100,000 vehicles/100,000 mi = 100 tn CO2 (min)

Equal # of vehicles driven 24/7/365 capture < 1 million tns C annually 876,000 C tns

Two early work capture comparisons to 2015  

We compare our results [2009] [ref 1] and 2015 (above) with Ebune G. findings (2008): 

  • Reactants/Products K2CO3 + 1.5H2O + CO2 <--> 2KHCO3 + 0.5H2O + heat
  • Quantity mol CO2 2.5 to 3.5 / mol K2CO3 (potassium carbonate)

Ebune, G. Carbon Dioxide Capture from Power Plant Flue Gas using Regenerable Activated Carbon Powder Impregnated with Potassium Carbonate 2008

Our [Murray et al 2009] CO2 capture efficiency then was 50%   

We found 3 mols CO2 (132.30 grams) locked into 138.29 grams of K2CO3 (4.87 ounces) 

In this case, starting material KOH (mol KOH) = 56.05 grams 3.95 ounces of KOH

What are other key benefits?

Other key benefits

Natural geochemical CO2 sequestration is slow; a derived method can potentially accomplish the same task in minutes.

CO2 for storage credit or reuse in aquaculture respiration (algae/fish); amendment successfully adds to depleted soil, promotes growth

Metro CO2, dominant GHG species may be captured & safely retained as inert solid

Benefit beyond GHG reduction, investment provides work, strengthens economy

Carbon reduction byproduct benefits soil and water life-form growth

Recent evidence CO2 solid in nutrient-depleted soils promote abundant plant growth absent in controls


What are the proposal’s costs?

Most efficient 

Lowest cost/highest output-per-volume method is an automated one. Manufacturing parts stamped-out from molds use of computer programmed tooling.  Method requirements  machine drawings, specific software,  significant start-up expense. Example mold would making based on fleet-vehicle type, year-model intended  pollution control retrofit upgrades. 

Estimate/Filter_ mold/build  for machine to stamp out filter parts in volume production assessment by manufacturers offering to share cost for regional provincial market rights/build  offshore       $10-20K

Parts for CO2FD, this method Low Cost                                     $10 

Auto/Manufacturing_Start-up United States $10-25M

Low efficiency alternative

Lower-cost/lower-volume output option (not recommended)  farming-out parts to build detailed SolidWorks drawings  local machine shops, custom-made approach dedicating 1000 sq ft floor space/100 unit mfg/person/month  dedicated tooling leased / purchased welders,rollers,cutters, etc


Custom CO2FD (1) designed_installed_leak-tested                           Referenced ongoing [6] $2,700

Filter design_fleet build/test prototype $12K

Filters 100 build/Install/service/(1-yr) $100K                

Technology Advisor, p/t  annual $30K

 start-up conventional-venture capital. 

Other unconventional, accelerated return note (ARN):

investment return (ROI)  capped total ROI without

downside protection like traditional ARN, envisioned  short to medium range debt instrument funding with restricted appeal to  segment of investors knowing investment only appreciate marginally before ARN maturity, will not decline sharply dollar-wise in value. However, unlike traditional ARN, carbon company investment, while never declining sharply in value, will appreciate its ROI dollars equal to t market value of carbon.


  • transport vehicles
  • bus and transit fleets, etc




Time line

2016    J    F    M    A    M   J   J   A   S    O     N      D     2017     J   F    M


 _All Prep__________|

Permits I,___________II


         Sensor Network___|

         Filters, Transit I,__________________| Filters, Transit II,_______|


Implementation Incremental_______________________________________________

                                     Phase I            Phase II

  •   Curbing Emissions         Curbing Emissions
  •   Vehicle I                                            Vehicle II
  •   Street Traffic Filtration               Street idle & speed control


Development Items_____________________________________|

Considerations on recurring themes 

1.  Back pressure is outdated yet remains a concern and mostly applies to older technology vehicles without electronic features, or electronic controls of on-board computers capable of real-time adjustments.  The important consideration on this topic for modern vehicle reference, is don't leave a large empty opening in the exhaust flow that will swing flow pressure beyond the capability of compensation. Otherwise, the vehicle Check Engine light will illuminate due to a pressure differential detected beyond the programmed set-points. Properly installed and leak-tested, retrofits should fall within the programmed limits when welded to a continuous flow on stock systems and the Check Engine light will not illuminate.

2.  Stoichiometric or theoretical calculation of combustion reactants equals total mass of the products and exact mixing proportions to efficiently burn all fuel completely.  In reality, internal combustion engines are inefficient.  All fuel does not burn. However, with air:fuel ratios commonly 14:1, one gallon of gasoline (6 pounds) will produce about 19 pounds of CO2.

The intent here is to capture as much as possible. Initially, only fractions of output are captured, but even these amounts are considered better than nothing.   


Combustion reaction of methane.jpg   


Related proposals

Flue-gas CO2 capture by Accelerated Weathering

Emission from power plants producing electrical energy is reduced by accelerated weathering of limestone just as rock weathering will naturally dissolve limestone into bicarbonates over geological time. Accelerated weathering of flue gas CO2 emissions with limestone dust and water, dissolves the CO2 rapidly to bicarbonate ions. (Rau, et al)  [21]  (Murray et al) [23] 

Natural weathering and accelerated weathering both have equivalent impacts when bicarbonates enter seawater storage and biotic uptake. 

Bicarbonate ions and mineral cations remove for the long-term, CO2 from the hydrosphere by precipitating carbonate. 

Second, CO2 is immobilized by marine biotics until eaten or sinking calcareous remains to sea floor mud where remain build to stratified layers compressed chalk and under more/heat limestone formations of calcium carbonate, etc. and marble, etc., until finally graphite the representing most stabilized removal of atmospheric CO2.  



[1] Murray, K.D. Murray, K.A.,Vehicle exhaust 5-gas analysis before/after method for CO2 reduction, 2009:


[3]      United States Clean Air Act, 42 U.S.C. § 760

[4]  Excessive heat from urban topography and city traffic, are directly tracked to formation of aerosols, sulfates, nitrates, and ozone..

[5]      The Hydrospherewww.earthonlinemedia.com292 × by image

[6]    ​   Huybers, Peter J., and Charles Langmuir, Feedback between deglaciation, volcanism, and atmospheric CO2, Earth and Planetary Science Letters, 2009.

[7]       Bill Bryson, A Short History of Nearly Everything, BroadwayBooks, 2003.

[7]    White Cliffs of Dover

[8]        Murray, Kenneth D., "Curbing traffic emissions with carbon dioxide removal", February, 2015.

            Experimental filter, center

  [9]     High performance capability with experimental CO2 filter reduces carbon emission on Mercedes Benz ML350. Mineral combination traps CO2 molecules, accelerates natural geochemical capture/storage.


[11]    Cave system in Vietnam, National Geographic, 2015.


[12]    Cave environment, a natural CO2 trap for long-term carbon storage evidenced by mineral carbonate precipitates is study under consideration for MIT Climate Colab,m  Geoeng. proposal, CO2 air capture and long-term removal using the carbonate cavern conditional response atmospheric pressure, Murray, Geoengineering Workspace, MIT Climate CoLab, 2015.

[13]    Microbial controls on Panthalassan Carboniferous-Permian oceanic buildups, Japan

H Sano, K Kanmera - Facies, 1996 - Springer


[14]     National Academy of Sciences (NAS) Report on Carbon Dioxide Removal (CDR), Februray, 2015

[17]     Seinfeld, John H.; Pandis, Spyros N. (1997), Atmospheric Chemistry and Physics: From Air Pollution to Climate Change, Wiley-Interscience, ISBN 0-471-17816-0

[18]     Yegulalp T.M., K.S. Lackner and H.J. Ziock, “A Review of Emerging Technologies for Sustainable Use of Coal for Power Generation,” presented at Sixth International Symposium on Environmental Issues and Waste Management in Energy and Mineral Production, Calgary, Alberta, Canada, May 30-June 2 (2000).

[19]    Recent Developments and Outlook for Clean Energy from Coal without Combustion T.M.Yegülalp Henry Krumb School of Mines, Columbia University, New York, NY 10027, USA

[20]    Carbon dioxide sequestration by mineral carbonation Literature Review W.J.J. Huijgen & R.N.J. Comans

[21]  Caldeira, K., and G.H. Rau, Accelerating carbonate dissolution to sequester carbon dioxide in the ocean: Geochemical implications, Geophysical Research Letters, 27, 225–228, 2000.

[22]    G. Rau, et al, U.S. Patent 7,655,193 Feb 2010; U.S. Patent 8,177,946  May 2012.

[23]    K. Murray, et al, U.S. Patent 7,914,758 Mar 2011; U.S.Patent 8211394, July 2012.