Biomineralized Materials for Sustainable and Durable Construction

what is the composition of conventional portland cement?

95% clinker, 5% gympsum

outline the process of portland cement production?

1. Materials are sintered in cement kilns, forming clinker

2. Water is added to ground clinker to produce calcium silicinate hydrate

3. Calcination converts calcium carbonate into carbon dioxide.

4. Gypsum is added to added to increase the setting time.

microbial biomineralization

leverages biominerals produced by the metabolism of microorganisms

what is application of biomineralization to portlad concrete

calcium carbonate from microbes are used as a cementing materials; biominerals form their own biocement

what are some challenges when dealing with microbial biomineralization?

long-term microbe viability

passive biomineralization/biologically induced mineralization

normal biological processes (pH changes, release of metabolic byproducts, etc.) cause changes to the surrounding environment and induce precipitation of biominerals

active biomineralization/biologically controlled mineralization

living organisms direct precipitation of biominerals

extracellular biologically controlled mineralization

biominerals are precipitated in external organic matrices after passive diffusion of ions from inside cells

intercellular biologically controlled mineralization

controlled secretion of ions from inside cell

intracellular biologically controlled mineralization

1. specific ions are pumped into cells from the environment

2. specialized internal compartments actively combine transported ions into specific mineral phases

3. minerals are secreted to outside surface of cell

what are examples of precipitated minerals from biomineralization

carbonates, phosphates, silicates, metal-containing complexes

which precipitated minerals are important for construction materials research

metal-containing complexes (remediation of contaminated sites)

which precipitated minerals are important for sustainable cement and concrete research

polymorphs of calcium carbonate

what are the various polymorphs for calcium carbonate

trigonal calcite, hexagonal vaterite, orthorhombic argonite, amorphous calcium carbonate phases

how can we tell which phase of calcium carbonate will precipitate?

the microorganism selected, the mienralization pathway, and the environmental conditions

microbially induced calcite precipitation (MICP)

passive biomineralization of calcium carbonate

what are the main calcium carbonate biomineralization pathways discussed

urea hydrolysis, photosynthesis, sulfate reduction

what is the most widely applied and studies calcium carbonate biomineralization pathway

urea hydrolysis

process of urea hydrolysis

1. microbes produce urease enzyme

2. enzyme hydrolyzes urea, which ultimately produces carbonate and ammonium ions

3. carbonate ions react with dissolve calcium ions to produce calcium carbonate

where do the calcium ions needed for urea hydolysis come from?

ureolytic biomineralizing microorganisms have a negative cellular surface charge

what aspects of ureolytic microorganisms make them appealing for cement and concrete applications?

they are resilient to extreme environmental pressure that are inherent within cement and concrete materials

what are some drawbacks of urea hydrolysis?

cost of urease enzyme production, amount of nutrient addition required (organic carbon and urea), production of ammonia

photosynthesis and biomineralization of calcium carbonate procedure

1. carbon dioxide is rereleased as a byproduct of ATP production during photosynthetic respiration

2. carbon dioxide reacts with water to produce carbonic acid, wit the help of carbonic anhydrase (CA)

3. carbon acid dissociates to produce bicarbonate ions

4. bicarbonate ions react with calcium ions to precipitate calcium carbonate

why is photosynthetic calcium carbonate biomineralization gaining traction?

it can sequester carbon dioxide during cell growth and biomineralization, requires less exogenous nutrient additions

what are drawbacks of the photosynthetic pathway?

requires lots of sunlight and carbon dioxide

what are the two pathways of biomineralization through sulfate reduction

abiotic disassociation of calcium sulfate, reduction of calcium sulfate

describe the abiotic dissociation of calcium sulfate pathway

1. calcium sulfate dissociates

2. sulfur-reducing microorganisms reduce sulfate to hydrogen sulfide, releasing HCO3-

3. HCO3- reacts with calcium ions to precipitate calcium carbonate

describe the reduction of calcium sulfate pathway

1. sulfate-reducing bacteria reduce calcium sulfate, producing calcium sulfide

2. calcium sulfide reacts with water to produce calcium hydroxide

3. calcium hydroxide reacts with carbonic acid to precipitate calcium carbonate

what are the benefits of sulfur-reducing bacteria

their apparent suitability to highly alkaline regions increases their usefulness in the high-pH environment of portland cement concrete, anaerobic, only require organic carbon addition

what are drawbacks of sulfur reduction as a biomineralization pathway?

produces toxic H2S gas, suflate-reducing organisms are less resilient because they are gram negative

what are some other calcium carbonate biomineralization pathways

denitrification, organic compound conversion

briefly describe the denitrification pathway

anaerobic microorganisms reduce nitrate to nitrogen gas, which precipitates calcium carbonate when carbon dioxide and calcium ions are present

briefly describe the organic compound conversion pathway

microorganisms directly convert organic compounds to calcium carbonate

what are the methods used to apply biomineralization in construction

bioaugmentation and biostimulation

bioaugmentation

addition of microbial cultures to a construction material during the manufacturing process

biostimulation

addition of nutrients to selectively stimulate indigenous microorganisms

what is the more common biomineralization application technique and why

bioaugmentation due to level of control and selection

what are the advantages of biostimulation

lower cost, enhanced ease of application, lower environmental safety concerns

what species are the most common biomineralization microorganisms used in construction materials science rsearch

genus Bacillus

Sporosarcina pasteurii

most common biomineralizing microorganism; nonpathogenic and ureolytic

what are the benefits of microbial isolation

microorganisms are well adapted to local environmental additions

what are the most studied applications of biomineralization in construction

historic preservation, soil stabilization, self-healing conrete, production of biomineralized concrete-like structures

biodeposition

biomineralizing microorganisms grow on facades of masonry structures or artworks made from gypsum or limestone, providing durable calcium carbonate layers

benefits of biodeposition

decreases porosity, water permeability, increases mechanical strength, prevent internal deterioration inherent in synthetic of chemical treatment methods

biogrouting

biomineralizing microorganisms are injected, premixed, or percolated into sand and soil, precipitating calcium carbonate

what are benefits of biogrouting

bioclogging of soil, biocementing increases soil stiffness and strength, decreased soil permeability and hydraulic conductivity, decreased liquefaction risk in earthquakes, improved erosion control, stabilization of loose-aggregate pavements

what are commercial challenges of soil biocementation

system design, control, optimization due to soil heterogeneity

premise of self-healing concrete

adding biomineralizing microorganisms, nutrients, and moisture, can lead to filling of surface cracks and seal microcracks

why is surface application preferred to mixture of biomineralizing microorganisms for self-healing concrete

microorganisms are less likely to be adapted to extreme chemical environment (alkalinity and low oxygen) of concrete; shear of mixing reduces viability

how can microbial viability be promoted in self-healing concrete

immobilization and encapsulation of microorganisms in other materials (biochar, metal and graphite nanoparticles, natural fibers, etc.)

recycled concrete aggregates and biomineralization

biomineralization can improve the surface properties of recycled aggregate

biomineralization and rammed earth construction

biominerals can create a biomcement to increase compressive strength and decrease water absorption

3D printing and biomineralization

an extension of bioaugmentation

1. printed structure contains lyphilized biomineralizing ureolytic microorganisms

2. structure is exposed to calcium chloride and urea solution

3. biomineralizing sand produces calcium carbonate, cementing sand particles

benefits of multiple-dose nutrient approach

increased microbial viability and biomineralization efficacy

compressive strength and water absorption of biomineralized building materials

biomineralized building materials have higher compressive strength and decreased water absorption relative to controls

compressive strength and nonbiomineralizing organisms

some studies show changes in compressive strength for nonbiomineralizing organisms and dead cells

what are some emerging ideas in biomineralization of building materials

living building materials, martian biomineralized concrete, synthetic biology

living building materials

made from sand gelatin, biomineralizing photosynthetic organisms; increases biological viability and improve mechanical propertie

martian biomineralized concrete

microorganisms can produce buildings materials and reduce need for exporting portland cement and concrete through anaerobically digesting martian rocks

synthetic biology and biomineralization

genetically modifying organisms can introduce biomineralization capabilities and enhance existing ones

other biological approaches to biocementation research

focus on reduction of carbon dioxide emissions through reprecipitating calcium and carbonate ions as a calcium carbonate biogrout

what are some general challenges in the field of biomineralization for construction application at the laboratory scale?

material optimization (microorganism growth and biomineral production) and property enhancement

what are some general challenges in the field of biomineralization for construction application at the commercial scale?

safe and sustainable application outside the lab, compliance with biosafety laws, scale-up feasibility and cost realism, promoting interaction between biology, civil engineering, and materials science fields