Para Nitro Chloro Benzene
Para Nitro Chloro Benzene — PNCB — is the workhorse feedstock behind para-nitroaniline (PNA), para-phenylenediamine (PPD) and para-aminophenol (PAP), the last of which is the key intermediate for paracetamol. It is also a direct route into azo and sulphur dye chemistry and rubber antioxidant intermediates.
Chelora Chemicals supplies PNCB to dye houses, pharmaceutical-intermediate manufacturers and rubber-chemical producers worldwide, in flakes or drums, with a batch COA and GHS safety data sheet on every consignment.
Product identity
- CAS Number
- 100-00-5
- IUPAC name
- 1-Chloro-4-nitrobenzene
- Molecular formula
- C6H4ClNO2
- Molecular weight
- 157.55 g/mol
- EC / EINECS
- 202-809-6
- MDL number
- MFCD00000481
- SMILES
- Clc1ccc(cc1)[N+](=O)[O-]
- HS Code
- 2904 91*
* Confirm the exact HS heading with your customs broker — classification of nitro-halogen aromatics varies between destination tariffs.
What Para Nitro Chloro Benzene is used for
PNCB is made by nitrating chlorobenzene, and it carries two reactive handles on one ring: a nitro group that can be reduced to an amine, and a chlorine activated toward nucleophilic displacement by that same nitro group. Together they make the molecule a genuine two-step building block rather than a single-reaction intermediate.
Reduce the nitro group and you reach para-nitroaniline — itself a diazo component for azo dyes and pigments and a direct precursor to para-phenylenediamine, the hair-dye and rubber-antioxidant amine. Displace the chlorine with hydroxide instead and, after reduction, you reach para-aminophenol, the key intermediate consumed by the paracetamol (acetaminophen) industry. Very little PNCB itself is used as-is; it is almost always converted on to one of these downstream amines.
Why the isomer matters
Nitration of chlorobenzene gives a mixture of isomers, and separating them cleanly is most of the value in a well-run PNCB plant:
- 4-Nitrochlorobenzene / PNCB (CAS 100-00-5) — this product. Nitro group para to the chlorine. The higher-volume of the two major isomers, feeding PNA, PPD and PAP.
- 2-Nitrochlorobenzene / ONCB (CAS 88-73-3) — the ortho isomer, feeding ortho-phenylenediamine and benzimidazole-based agrochemical and dye chemistry.
- 3-Nitrochlorobenzene / MNCB (CAS 121-73-3) — the meta isomer, a minor co-product with its own dye-intermediate outlets.
If your purchase order simply says "nitrochlorobenzene", quote us the CAS number and we will confirm the correct isomer before the order is placed. Sister isomers and related nitro-aromatics are available on request — see our full product range.
Appearance and handling character
PNCB ships as a pale yellow crystalline solid or flake melting around 83 °C — comfortably above ambient in most climates, but low enough that a hot warehouse roof or a tropical container can soften a poorly ventilated pallet. It is practically insoluble in water and dissolves readily in aromatic and chlorinated solvents. It carries a faint, sweetish aromatic odour typical of nitroaromatics.
| Parameter | Typical value |
|---|---|
| Appearance | Pale yellow crystals / flakes |
| Assay (GC) | 99.0% min |
| Ortho-isomer content | 0.5% max |
| Melting range | 81 – 84 °C |
| Moisture | 0.2% max |
| Colour (molten) | Reported per batch (APHA) |
Important: the figures above are indicative of commercial grade material and are offered for planning only. The batch certificate of analysis is the governing document. Dye and paracetamol-chain buyers in particular should send their own ortho-isomer and colour limits so we can source to spec rather than to a generic grade.
| Property | Value |
|---|---|
| Physical state | Crystalline solid at ambient |
| Melting point | ≈ 83 °C |
| Boiling point | ≈ 242 °C @ 760 mmHg |
| Flash point | ≈ 127 °C |
| Relative density | ≈ 1.52 |
| Partition coeff. (log P) | ≈ 2.39 |
| Water solubility | Practically insoluble (≈ 0.35 g/L) |
| Organic solubility | Soluble in benzene, toluene, chlorinated & aromatic solvents |
| Odour | Faint, sweetish aromatic |
Physical constants compiled from public reference data for CAS 100-00-5 and rounded for readability. Treat them as orientation, not as a specification.
Where our customers put this molecule to work
PNCB's value is almost entirely downstream — in the amines and phenols it converts into. Its two-handle structure keeps it central to three separate industries.
Para-nitroaniline (PNA)
Ammonolysis of the chlorine gives PNA directly. PNA is itself a major diazo component for azo dyes and pigments, and the standard entry point to para-phenylenediamine.
- Displacement of chlorine by ammonia
- Feeds red and orange azo pigment chemistry
- Isomer purity carries straight through to shade
Para-phenylenediamine (PPD)
Reduction of PNA's nitro group gives PPD — the key rubber antioxidant and oxidative hair-colourant amine, and a precursor to aramid-fibre chemistry.
- Rubber antidegradant intermediate
- Oxidative hair-dye amine
- High-purity grades command a premium
Para-aminophenol (PAP) & paracetamol
Hydrolysis of the chlorine to a phenol, followed by nitro reduction, gives PAP — the direct precursor acetylated into paracetamol (acetaminophen). This is one of the highest-volume pharmaceutical intermediate chains built on PNCB.
- Feeds the global paracetamol API chain
- Pharma-grade buyers specify tight heavy-metal limits
- Also used in photographic developer chemistry
Dye & pigment chemistry
Beyond PNA-based azo colour, PNCB itself is a starting point for sulphur dyes and for nitro-diphenylamine intermediates used in vat and disperse dye ranges.
- Sulphur dye intermediate chemistry
- Nitro-diphenylamine routes
- See our dye intermediate range
Rubber & agrochemical chemistry
The chlorine also serves as a handle in fine synthesis for rubber-chemical and agrochemical intermediates where a 4-nitrophenyl fragment is required.
- Custom nucleophilic-substitution chemistry
- Nitro group available for later reduction
- Available in trial and laboratory quantities
Contract & scheduled supply
Paracetamol-chain and dye plants typically run to annual campaign volumes. We hold contracted tonnage and release it to your production plan rather than in one shipment.
- Annual contracts with scheduled call-off
- Price held across the contract period
- Second source held in reserve
How we supply Para Nitro Chloro Benzene
Chelora Chemicals is a supplier and sourcing partner, not a manufacturer. We own no nitration plant — and for an isomer-sensitive intermediate like this one, that independence works in your favour. We are never obliged to push you whatever a captive unit happens to be running that month.
Instead we place your order with whichever qualified producer best matches your assay, your ortho-isomer tolerance, your price point and your delivery window.
We keep a second qualified source on this line. When a plant goes down for maintenance, or a monsoon disrupts a road corridor, your campaign switches source rather than stalling.
- Specification read against the CAS first. We confirm you need 100-00-5 and not the ortho or meta isomer before we quote a price.
- Batch COA shared before dispatch. You approve the assay, isomer content and colour profile against your own spec while the material is still in our warehouse.
- Hazard status stated up front. This material carries acute toxicity and suspected mutagenicity classifications, and we say so at enquiry stage — not in the small print of a document pack that arrives with the goods.
- Pre-shipment samples for qualification. New account or new source, your R&D team runs a lab batch before the full quantity ever moves.
- Packing chosen for your climate. With a melting point around 83 °C, pack format and stowage matter on a hot routing. We plan both with you.
- Export machinery handled in-house. Hazard classification, UN-approved packing, labelling, freight booking and customs paperwork are ours to manage.
- Consolidation onto one bill of lading. Ship PNCB alongside other intermediates from our range — one invoice, one shipment, one counterparty.
Packed the way your plant receives it
Pack format drives your landed cost and your handling effort — and for a nitroaromatic with an acute-toxicity profile, it also drives operator exposure. Tell us how it will be charged at your end and we will quote the format that suits your operation.
Multi-wall paper & PE bags
Laminated multi-wall bags with an inner liner, palletised and shrink-wrapped. The default for LCL movements and for plants charging batch-wise by hand.
Fibre & HDPE drums
UN-certified drums with liner for longer sea transits and humid destinations. Better protection against moisture pick-up and caking than bagged material.
Jumbo / FIBC bags
Bulk bags with liner for high-volume dye and paracetamol-chain users with mechanical charging. Fewer handling movements and materially lower packing cost per kilo.
Samples & trial packs
Laboratory samples and pilot quantities dispatched by courier so your R&D team can qualify the grade before committing to campaign volume.
Incoterms to suit you
Quoted on the Incoterm your purchasing team works to. Ocean, air and road freight arranged end-to-end with documentation filed before booking.
Campaign despatch
Dye and paracetamol-chain production runs to campaign. We hold contracted tonnage and release it against your production calendar instead of landing it all at once.
Handle this as an acute-toxicity nitroaromatic
This is the point on the page that matters most. Para nitro chloro benzene is acutely toxic by all three routes, is a recognised methaemoglobin former, and carries a suspected mutagenicity classification in major regulatory regimes. The summary below is orientation only — the safety data sheet supplied with your consignment is the authoritative document and should govern your risk assessment, PPE selection, exposure monitoring and emergency planning.
Classified hazards
H301Toxic if swallowed.H311Toxic in contact with skin.H331Toxic if inhaled.H341Suspected of causing genetic defects.H373May cause damage to organs (blood) through prolonged or repeated exposure.H410Very toxic to aquatic life with long lasting effects.
Hazard statements reflect the harmonised GHS classification commonly published for CAS 100-00-5. Supplier classifications may differ in detail; always read the SDS issued with your specific batch, and treat the methaemoglobinaemia risk as the one that shapes your medical response planning.
Spill & emergency orientation
Plan your response before the pallet arrives, not after a bag splits. The points below are orientation for your emergency planners — sections 4, 5 and 6 of the SDS are the authoritative instructions and should be posted at the point of use.
- Sweep, do not hose. The material is very toxic to aquatic life. Collect spilled solid mechanically into a labelled container; never wash it to a drain.
- Suppress dust. Dry sweeping of a fine solid generates an inhalable aerosol — use vacuum collection or dampen carefully in line with the SDS.
- Assume skin absorption. Contaminated clothing is a continuing exposure route — remove it immediately and wash the skin thoroughly.
- Have the SDS with the casualty. Nitrochlorobenzenes are recognised methaemoglobin formers, and the treating clinician needs the product identity and CAS number in hand.
- Record the exposure. For a material carrying a mutagenicity flag, most occupational regimes expect an exposure record to be created and retained. That is a decision for your EHS function, and it is easier made before an incident than after one.
Storage
- Cool, dry, well-ventilated store, away from direct sunlight and heat sources. The melting point is around 83 °C, so a hot uncooled store can soften or fuse the contents into a cake.
- Keep containers tightly closed. Moisture pick-up affects downstream reduction and displacement chemistry, and an open bag invites contamination.
- Segregate from reducing agents, strong bases and combustible materials. As a nitroaromatic it can react with reducing agents and is an oxidiser risk in a fire.
- Access-controlled storage. With acute toxicity and a mutagenicity flag, restricting who can reach the store is part of the control, not an administrative nicety.
- Shelf life is typically 24 months in sealed original packing under these conditions. Re-assay before use after long storage.
Handling & PPE
- Design exposure out, do not manage it down. Closed transfer and mechanical charging first, ventilation second, PPE last.
- Skin protection is the priority. Nitrochlorobenzenes are absorbed through intact skin and are a recognised cause of methaemoglobinaemia — chemical-resistant gloves and coveralls, not just splash protection.
- Respiratory protection where dust may be generated — particularly when breaking a caked drum or emptying a bulk bag — per your own exposure assessment.
- Health surveillance and exposure records. Where local regulation triggers obligations at your site for a mutagen-flagged material, your occupational health provider and EHS function own the detail. We flag the classification; the programme is yours to run.
- Never discharge to drain or watercourse. H410 applies — collect spills as solid waste and dispose of them as regulated chemical waste.
Transport
PNCB moves as regulated cargo. We classify each consignment, apply UN-approved packaging and labelling, and file the dangerous-goods declaration before the booking is made. The applicable UN number, class and packing group are stated on your shipping documents and SDS — ask us for the current DG paperwork when you plan the shipment.
What travels with every consignment
A chemical shipment is only as good as the file that travels with it. Verifying what the source plant sends is precisely the work you are buying from a supplier.
Certificate of Analysis
Batch-specific assay by GC, ortho-isomer content, moisture, appearance and melting range — checked against your purchase specification before we release the goods.
GHS Safety Data Sheet
Full 16-section SDS in GHS format covering hazards, exposure controls, handling, storage, spill response, toxicology and disposal — issued in the language your destination requires.
Dangerous Goods Declaration
UN number, hazard class, packing group and IMDG or IATA declaration prepared and filed before the container is booked, with correctly marked and labelled packaging.
Certificate of Origin
Chamber-attested where required, plus preferential-origin forms where a trade agreement gives your import duty relief at the destination.
Third-party inspection
SGS, Intertek or Bureau Veritas sampling and inspection arranged on request before loading, giving you independent verification of what actually ships.
Retained & pre-shipment samples
Pre-shipment samples carry the same COA as the commercial lot, so what your laboratory qualifies is exactly what arrives. Retention samples held against the batch.
The two doors out of this molecule
Almost everything made from PNCB leaves through one of two reactions: reduction of the nitro group, or displacement of the chlorine. Understanding which one you are using explains why the specification matters and which impurity will hurt you. The routes below are the general industrial pattern, not a process disclosure.
Start with PNCB
Chlorobenzene nitration gives a mixture of isomers; PNCB is isolated and purified, leaving the para-nitro/para-chloro pattern that carries through everything built from it.
Door one — ammonolysis
The nitro group activates the ring toward nucleophilic aromatic substitution — ammonia displaces the chlorine to give para-nitroaniline directly.
Door two — hydrolysis then reduction
Hydroxide displaces the chlorine to give a nitrophenol, which is then reduced to para-aminophenol — the paracetamol-chain route.
Finish to grade
The crude amine or phenol is crystallised, washed and dried, then standardised or purified to whatever the end market demands — pharma limit, dye-shade target or rubber-grade spec.
Why isomer purity carries through the whole route
Both doors act on a ring that already carries the isomer pattern set at the nitration step. Anything off-pattern in the feed follows the material down the line:
- The ortho isomer (ONCB) reacts in parallel and gives ortho-substituted co-products — an off-shade chromophore in azo work, an impurity that must be purged before the paracetamol step.
- Residual dinitro species from over-nitration carry through as colour bodies and can complicate downstream reduction.
- Moisture and acid carryover from the nitration wash affect both the ammonolysis and hydrolysis steps and are worth specifying tightly.
- Heavy-metal residues matter disproportionately for the paracetamol chain, where pharmacopoeial limits apply from PAP onward.
That chain of consequences is the reason we quote against your written specification rather than a generic "99% technical" grade, and the reason the batch COA is shared for approval before dispatch rather than sent with the invoice.
| Downstream product | Principal outlet |
|---|---|
| Para-nitroaniline (PNA) | Azo dyes & pigments |
| Para-phenylenediamine (PPD) | Rubber antioxidants Oxidative hair dyes |
| Para-aminophenol (PAP) | Paracetamol / acetaminophen Photographic developers |
If your route calls for the ortho isomer, one of these downstream amines directly, or a related nitro-aromatic, tell us the CAS number or the finished molecule you need and we will source accordingly — see our full product range.
What actually moves the price of this intermediate
PNCB is not a commodity with a screen price. Knowing what drives the quote helps you time a purchase and read whether an offer is realistic.
The paracetamol cycle
A large share of PNCB demand ultimately tracks paracetamol API production, which itself follows generic-pharma tender cycles and seasonal cold-and-flu demand. That cycle can move faster than the dye-side demand for the same molecule.
- Quote early ahead of pharma tender seasons
- Spot buying at peak costs materially more
- Contracted call-off smooths the exposure
Upstream feedstock
The route back to PNCB runs through chlorobenzene, nitric and sulphuric acid. Movements in benzene, chlorine and mixed-acid pricing feed through to the nitroaromatic within a quarter or so.
- Chlorobenzene and nitric acid set the floor
- Energy cost weighs on separation and drying
- We flag feedstock-driven moves in the quote
Regulatory pressure
The mutagenicity flag raises the compliance cost of producing, storing and moving this material. That cost sits inside the price, and it is one reason capacity has consolidated rather than expanded in some regions.
- Handling obligations vary by jurisdiction
- Pharma-grade buyers face extra audit requirements
- We check destination rules before quoting
Pack format
Cost per kilo falls from 25 kg bags to drums to jumbo bags — and with an acute-toxicity solid, bulk bags also cut the number of times an operator opens a pack.
- Small bags carry the highest packing cost
- FIBC is cheapest per kilo at volume
- Less manual handling means less exposure
Freight & DG surcharges
This is regulated cargo, so ocean freight carries a hazardous surcharge and space is tighter than for general cargo. Destination and Incoterm move landed cost as much as the ex-works price does.
- Compare on landed cost, not ex-works
- DG space books out ahead of peak season
- We quote FOB, CIF, CFR or DDP as you prefer
Source availability
A plant turnaround, an environmental inspection or a monsoon disruption can take capacity offline at short notice. Single-sourced buyers feel this hardest.
- We hold a second qualified source on this line
- Qualify the alternate before you need it
- Ask us about dual-source contracts
| If your end use is… | Specify |
|---|---|
| PNA / azo dye route | Low ortho-isomer, colour ceiling |
| PPD / rubber chemical route | High assay with tight isomer limit |
| PAP / paracetamol chain | Pharma-grade heavy-metal and residue limits |
| Sulphur dye chemistry | Colour and moisture the critical parameters |
| Laboratory / R&D | Small pack, high purity, full analytical pack |
Not sure which column you are in? Describe the reaction you are running and our technical desk will recommend the grade — including telling you when a cheaper specification would do the job just as well.
Support that goes beyond shipping the bag
What our technical desk will do
- Match a grade to your reaction. Tell us the step you are running — ammonolysis, hydrolysis or a custom substitution — and we will recommend the specification.
- Be straight about the hazard profile. We state the acute-toxicity and mutagenicity classifications at enquiry stage so your EHS team can price the controls into the decision, rather than meeting it for the first time on the label.
- Advise on handling and storage for your site conditions — a bagged store in a Gulf summer is a different problem from one in northern Europe, especially for a solid that melts at 83 °C.
- Review your specification before it goes into a contract, so you are not locked into a limit that no plant can consistently hit.
Regulatory & compliance notes
- Mutagenicity flags are jurisdiction-specific. Several regimes impose substitution reviews, exposure monitoring, health surveillance and record retention for suspected mutagens. Confirm what applies at your site before the first delivery.
- Import controls vary by destination. Some jurisdictions apply registration, licensing or end-use declaration requirements to nitro-halogen aromatics. We check the destination rules before quoting, not after you have raised the PO.
- Pharmacopoeial expectations apply increasingly far upstream on the paracetamol chain. If your buyer expects a full impurity and heavy-metal dossier at the PNCB stage, tell us and we will source accordingly.
- Chemical inventory listings differ between regions. Confirm your obligations under the applicable inventory regime for your import volume — we will supply the identity data you need for that filing.
None of the above is legal advice — your own regulatory affairs team owns the final compliance position for your import and your workplace. What we commit to is giving you accurate product identity data, an honest statement of the hazard classification and complete documentation to work from.
From enquiry to delivered pallet
Send the specification
Product name or CAS 100-00-5, the assay and ortho-isomer limits you work to, quantity, pack preference and destination port.
Receive a firm quote
Pricing, lead time, packing and Incoterm confirmed in writing within 24 hours — our sourcing desk is staffed around the clock.
Qualify and approve
Sample dispatched if you are qualifying a new source. Batch COA shared for your approval before the material is released.
Ship and track
DG classification filed, freight booked, export documents issued, and the consignment tracked through transit and clearance to your plant.
Often bought alongside this grade
Consolidate several intermediates onto one shipment and one invoice. These are the nitro-aromatics, chloro-aromatics and downstream amines our dye, pharma and rubber-chemical customers most often order in the same programme. Browse the full range for current availability and CAS-level detail on each.
What buyers ask us about Para Nitro Chloro Benzene
Is this material a suspected mutagen?
Can I use the ortho or meta isomer instead?
What purity do you normally supply?
What is the minimum order quantity?
How long does delivery take?
The material arrived caked or partly fused. Is it off-spec?
Why does the assay matter so much for the paracetamol chain?
How should we store it, and what is the shelf life?
Is this a dangerous good? What paperwork comes with it?
- Batch certificate of analysis
- GHS-format safety data sheet
- Dangerous-goods declaration with UN number, class and packing group
- Commercial invoice, packing list and bill of lading or airway bill
- Certificate of origin and any destination-specific forms
Do you supply to my country?
Do you manufacture this yourself?
Can you hold stock against a production plan?
Request pricing on Para Nitro Chloro Benzene
Send your required assay, quantity, pack format and destination port. Our sourcing desk is available 24 hours a day, 7 days a week, and comes back with pricing, lead time and packing options — whether that is a single trial bag or a contracted container programme for the year.