Sodium Bicarbonate (CAS 144-55-8): Properties, Production and Applications

What Is Sodium Bicarbonate?

Sodium bicarbonate (CAS 144-55-8), also called sodium hydrogen carbonate, bicarbonate of soda or baking soda, is a white, mildly alkaline crystalline powder with the formula NaHCO₃. It is one of the most widely used inorganic chemicals: a food-grade leavening agent and acidity regulator (E500), a rumen buffer in animal feed, a dry sorbent for acid-gas removal in flue-gas cleaning, a pH and alkalinity adjuster in water treatment, and a mild base in chemical and pharmaceutical processes.

PolyBlueChem supplies food-grade sodium bicarbonate to a controlled specification (NaHCO₃ 99% min, low arsenic and heavy metals) with per-batch COA and SDS. This guide covers its chemistry, production, specifications, properties, applications, comparison with other alkalis, dosage, safety and supply.

CAS number	144-55-8
Synonyms	Sodium bicarbonate; sodium hydrogen carbonate; bicarbonate of soda; baking soda; E500(ii)
Molecular formula	NaHCO₃
Molecular weight	84.007 g/mol
Appearance	White crystalline powder or fine granules
Food additive number	E500 (sodium carbonates); E500(ii) is sodium bicarbonate
Main grades	Food grade; feed grade; technical / industrial grade

Chemistry and Structure

Sodium bicarbonate is the acid sodium salt of carbonic acid. It contains a sodium cation (Na⁺) and a bicarbonate anion (HCO₃^–), in which the carbon atom is bonded to three oxygen atoms. The bicarbonate ion is amphoteric: it can neutralise an acid (releasing carbon dioxide) or act as a very weak acid (neutralising a base to give carbonate). This dual behaviour is what makes sodium bicarbonate a useful buffering and pH-control agent.

Two reactions matter most in practice:

With acid – bicarbonate reacts with an acid to release carbon dioxide: NaHCO₃ + H⁺ -> Na⁺ + H₂O + CO₂. This is the basis of baking, effervescent products, gas scrubbing and deodorising.
On heating – above about 50 °C sodium bicarbonate begins to decompose, and around 100 – 150 °C it converts to sodium carbonate with release of CO₂ and water: 2 NaHCO₃ -> Na₂CO₃ + CO₂ + H₂O. This is why baking soda loses strength if stored hot or used where high temperatures are held for long.

In water, sodium bicarbonate gives a mildly alkaline solution (about pH 8.3 for a 1% solution). Because the bicarbonate/carbonate equilibrium is pH-sensitive, sodium bicarbonate buffers a system near pH 8, while sodium carbonate buffers nearer pH 10 – 11.

How Sodium Bicarbonate Is Produced

There are three commercial routes. All end with a crystallisation step, because sodium bicarbonate is less soluble than the other salts present and can be crystallised out selectively.

Route	Feedstock	Principle
Solvay (ammonia-soda) process	Salt (NaCl), ammonia, limestone (CO₂)	Ammoniated brine is carbonated; sodium bicarbonate crystallises first and is filtered off, then calcined to soda ash. Bicarbonate is drawn off as an intermediate product where food-grade material is wanted.
Natural (trona) refining	Natural trona ore (sodium sesquicarbonate)	Trona is dissolved (calcined or by solution mining) and the liquor is carbonated/crystallised to give sodium bicarbonate; a large share of world supply comes from natural deposits.
Carbonation of soda ash	Sodium carbonate (soda ash) solution	Soda ash liquor is treated with CO₂ to crystallise sodium bicarbonate. Used where high-purity, food-grade crystals are required.

For food-grade material the control points are the purity of the feedstock and the washing/crystallisation stage, which set the arsenic and heavy-metal levels that distinguish food grade from technical grade.

Specifications and Grades

Sodium bicarbonate is sold in three broad grades. The chemical is the same; the grades differ in purity limits and in the tests applied.

Grade	Typical use	Key control
Food grade (E500)	Baking, beverages, food and pharmaceutical use	Tight arsenic and heavy-metal limits; whiteness and clarity
Feed grade	Animal feed and rumen buffering	Purity plus feed-safety limits (heavy metals, arsenic)
Technical / industrial grade	Flue-gas treatment, water treatment, cleaning, chemical use	Assay and physical form; less stringent metal limits

The food-grade material PolyBlueChem supplies meets the following specification:

Parameter	Specification
Content (as NaHCO₃)	99% min
Chloride (Cl)	0.4% max
Arsenic	0.0001% max
Heavy metals (as Pb)	0.0005% max
Loss on drying	0.20% max
pH value	8.5 max
Ammonium salt (NH₄)	Pass
Clarity	Pass
Whiteness	85 min

The arsenic (0.0001% max) and heavy metals as Pb (0.0005% max) limits are what qualify the material as food grade. Loss on drying (0.20% max) controls moisture and, indirectly, stability; whiteness (85 min) and clarity (pass) cover the appearance expected in food and beverage use. A specification sheet and a per-batch certificate of analysis (COA) are available on request.

Interpreting the Specification

Each line of the specification controls a different risk, so it is worth knowing what each one tells you when you read a batch COA.

Parameter	What it controls	Why it matters
Content (as NaHCO₃)	Active strength	Sets dosing and leavening performance
Chloride (Cl)	Residual salt from feedstock	Corrosion and off-taste in sensitive uses
Arsenic	Toxic-metal limit	Food and feed safety
Heavy metals (as Pb)	Toxic-metal limit	Food and feed safety
Loss on drying	Moisture	Stability and caking in storage
pH value	Alkalinity of the solution	Buffering and behaviour in dough or beverage
Ammonium salt (NH₄)	Residual ammonia	Purity (a Solvay-process residue check)
Clarity	Insoluble matter	Appearance in solution
Whiteness	Colour	Appearance in food use

Key Physical and Chemical Properties

Property	Value / behaviour
Form	White crystalline powder or granules
Solubility in water	About 9.6 g/100 mL at 20 °C (solubility rises with temperature)
pH (1% solution)	About 8.3 (mildly alkaline)
Decomposition	Begins above about 50 °C; converts to sodium carbonate around 100 – 150 °C
Behaviour with acid	Releases carbon dioxide (effervescence)
Behaviour with base	Acts as a weak acid, forming carbonate
Bulk density	Varies with grade and particle size (powder vs granular)

These properties explain the main uses: high, temperature-sensitive solubility and cheap CO₂ release make it a good leavening and scrubbing agent; mild alkalinity and buffering make it a safe pH adjuster; and the solid, free-flowing form makes it easy to store, dose and ship.

Applications

Sodium bicarbonate is used across food, feed, environmental and industrial applications. The table below maps the main industries to the function it performs.

Industry	Function	Why bicarbonate
Food and beverage	Leavening agent, acidity regulator (E500)	Releases CO₂ on heating or with acid; mild, food-safe base
Animal feed	Rumen buffer in dairy and beef cattle	Helps stabilise rumen pH in high-concentrate rations
Flue-gas treatment	Dry sorbent for acid gases (SO₂, HCl, HF)	Reacts with acid gases at moderate temperature; dry handling
Water treatment	pH and alkalinity adjustment	Mild, easy-to-dose alkaline source
Chemical and pharmaceutical	Mild base, buffer, CO₂ source, effervescent excipient	Controllable, low-hazard base
Cleaning and personal care	Mild abrasive, deodoriser, effervescent	Safe, mild and non-corrosive
Fire fighting	Dry-chemical extinguishing powder (BC)	Releases CO₂ to smother flame

Food and bakery – the classic chemical leavening agent. Reacting with an acid (or on heating) it releases CO₂ that raises dough and batter. Also used as an acidity regulator, in effervescent drinks and as a mild raising agent in many foods (see sodium bicarbonate in food and baking).
Animal feed – added to dairy rations as a rumen buffer, helping maintain rumen pH and intake in high-energy diets (see sodium bicarbonate in animal feed).
Flue-gas and environmental – injected as a dry sorbent to neutralise acidic gases; also used to adjust pH and alkalinity in water and effluent treatment (see sodium bicarbonate in flue-gas and water treatment).
Chemical synthesis – a mild base for pH control and a convenient source of carbon dioxide.

Sodium Bicarbonate vs Other Alkalis

Buyers often compare sodium bicarbonate with soda ash, caustic soda, potassium bicarbonate and ammonium bicarbonate. They differ in strength, pH, safety and cost, which decides the right choice.

Product	CAS	Formula	pH / strength	Typical role
Sodium bicarbonate	144-55-8	NaHCO₃	Mild base (~pH 8.3)	Food, feed, flue-gas, buffering, CO₂ source
Sodium carbonate (soda ash)	497-19-8	Na₂CO₃	Stronger base (~pH 11)	Glass, detergents, pH control, bulk alkali
Sodium hydroxide (caustic)	1310-73-2	NaOH	Very strong base	Neutralisation, pulp, soap, cleaning
Potassium bicarbonate	298-14-6	KHCO₃	Mild base	Low-sodium food and feed, agriculture
Ammonium bicarbonate	1066-33-7	NH₄HCO₃	Mild, releases ammonia	Some food/leavening and industrial CO₂

In short: choose sodium bicarbonate when you need a mild, safe base or a controllable CO₂ source; choose soda ash or caustic when you need more alkalinity per tonne; choose potassium bicarbonate where sodium is restricted. For a full decision table see sodium bicarbonate vs sodium carbonate.

Dosage and Formulation Notes

Doses are application-specific and must be confirmed by trial and by local regulation. The figures below are starting points only.

Application	Starting-point guidance
Baking / leavening	Set by the recipe and by the acid used; balance bicarbonate against the acid to avoid a soapy or bitter taste
Rumen buffer (dairy)	Typical inclusion is a small percentage of the ration dry matter, confirmed by a nutritionist and by rumen pH
Flue-gas dry sorbent	Set on the acid-gas load and target removal; stoichiometric ratio and excess determined by test
Water / effluent pH	Dosed to a target pH or alkalinity, controlled by titration or online pH

Because bicarbonate is a mild base, larger weights are usually needed than for soda ash or caustic to reach the same pH change. Always confirm the dose on your own system or recipe.

Safety, Handling and Storage

Sodium bicarbonate is a low-hazard material with a long history of food use, but the following points should be observed.

Dust – fine powder can cause mild mechanical irritation of eyes and the respiratory tract; use dust control or extraction where large amounts are handled.
Acid contact – contact with acids releases carbon dioxide rapidly; in closed spaces this can build pressure. Keep away from acids and do not store in sealed containers with acids.
Heat – above about 50 °C the material decomposes, losing CO₂ and gaining sodium carbonate; store cool for food and leavening use.
Moisture – keep sealed and dry; the powder should stay free-flowing.
Personal protection – good hygiene practice (eye protection and dust mask for dusty handling); wash after contact.

Regulatory and Food-Additive Status

Sodium bicarbonate is a long-established food additive and is authorised in most markets under the sodium carbonates group.

Market / framework	Status (as commonly cited)
EU (E numbers)	E500 sodium carbonates; E500(ii) is sodium bicarbonate
Codex / general food use	Recognised leavening agent and acidity regulator
Feed	Used as a rumen buffer, subject to local feed-safety limits
Industrial use	Not food-grade; grade chosen on technical requirements

Food safety limits (for example arsenic and heavy metals) differ between markets; confirm the applicable monograph and grade for your destination. PolyBlueChem supplies food grade with a per-batch COA and can provide the documentation your market requires.

Sourcing and Market Notes

Sodium bicarbonate is a high-volume, low-cost inorganic commodity, so sourcing turns on a few practical points rather than on brand.

Route and origin – material may come from natural trona refining or from synthetic (Solvay or soda-ash carbonation) routes. Both can meet food-grade specification; the certificate, not the route, is what you should buy against.
Food-grade share – only part of total production is finished to food grade (tight arsenic and heavy-metal limits, whiteness, clarity), so confirm the grade explicitly on the order and the COA.
Cost drivers – soda-ash feedstock, carbon dioxide, energy (calcination and drying), packaging and freight. These move the price, so terms are usually quoted on a committed tonnage and delivery basis.
Logistics – because it is a bulky, non-hazardous powder, delivered cost is dominated by freight and packing. Full container loads in jumbo bags are the most economical; part loads cost more per tonne.
Storage before use – order in line with consumption and keep stock cool and dry; long hot storage slowly converts bicarbonate toward carbonate.

Packaging, Logistics and Supply

Item	Standard options
Packaging	25 kg PP/PE bags; 1000 kg jumbo bags; palletised for container shipment
Documentation	Per-batch COA and SDS; other certificates on request
Incoterms	FOB and CIF
Delivery	Full-container and part loads to African and other export ports

Sodium bicarbonate is a commodity: price tracks the cost of the soda-ash feedstock (energy-intensive), carbon dioxide, packaging, energy and freight. Buying full container loads in jumbo bags gives the lowest delivered cost per tonne. For buying guidance see how to buy sodium bicarbonate.

Frequently Asked Questions about Sodium Bicarbonate

What is the CAS number of sodium bicarbonate?

Sodium bicarbonate is CAS 144-55-8; its formula is NaHCO₃ and its food additive number is E500(ii).

What is the difference between sodium bicarbonate and baking soda?

They are the same chemical. “Baking soda” is the common name for food-grade sodium bicarbonate.

Is sodium bicarbonate the same as soda ash?

No. Soda ash is sodium carbonate (CAS 497-19-8, Na₂CO₃), a stronger alkali; sodium bicarbonate (NaHCO₃) is milder and buffers near pH 8.

What grades do you supply?

Food grade to the specification above (NaHCO₃ 99% min, arsenic 0.0001% max, heavy metals 0.0005% max). Feed and technical grades can be discussed on request.

How is it used in animal feed?

Mainly as a rumen buffer in dairy and beef cattle rations to help stabilise rumen pH (see the feed guide).

Can it be used for flue-gas treatment?

Yes – it is injected as a dry sorbent to neutralise acid gases such as SO₂, HCl and HF.

How should it be stored?

Sealed and dry, away from acids and heat. It decomposes slowly above about 50 °C and releases CO₂ on acid contact.

What is the price trend?

As a commodity, bicarbonate tracks soda-ash, energy, packaging and freight costs. We offer competitive pricing on bulk and container volumes – contact us with your tonnage for current terms.