Quick Search

PRODUCTS

TEREPHTHALIC ACID

TPA

CAS Number: 100-21-0
EC Number: 202-830-0
Chemical Formula: C₆H₄-1,4-(COOH)₂
Molecular Weight: 166.13

Terephthalic acid is an organic compound with formula C6H4(CO2H)2. 
This white solid is a commodity chemical, used principally as a precursor to the polyester PET, used to make clothing and plastic bottles. 

Several million tonnes are produced annually.
The common name is derived from the turpentine-producing tree Pistacia terebinthus and phthalic acid.

Terephthalic acid (1,4-benzenedicarboxylic acid) is used for the production of polyesters with aliphatic diols as the comonomer. 
The polymer is a high-melting, crystalline material forming very strong fibers. 

Terephthalic acid is the largest volume synthetic fiber and the production of terephthalic acid is the largest scale operated process based on a homogeneous catalyst. 
More recently the packaging applications (PET, the recyclable copolymer with ethylene glycol) have also gained importance. 

Terephthalic acid is produced from -xylene by oxidation with oxygen. 
The reaction is carried out in acetic acid and the catalyst used is cobalt (or manganese) acetate and bromide. 

Phthalic anhydride is made from naphthalene or -xylene by air oxidation over a heterogeneous catalyst. 
The main application of phthalic anhydride is in the dialkylesters used as plasticizers (softeners) in PVC. 
The alcohols used are, for instance, 2-ethylhexanol obtained from butanal, a hydroformylation product.

Terephthalic acid is an industrially important aromatic acid, almost exclusively used as starting material for saturated polyester, mainly poly(ethylene terephthalate) (> 90%).
Terephthalic acid is almost entirely made by oxidation of petro-derived p-xylene. 

Pathways toward biobased p-xylene or terephthalic acid mainly focus on carbohydrates such as cellulose or hemicellulose.
Nonetheless, Yan and colleagues were the first to report a three-step process from corn stover lignin to terephthalic acid.

Starting from depolymerized RCF lignin oil, Terephthalic acid includes (i) a Mo on carbon catalyzed demethoxylation, (ii) a carbonylation of the obtained n-alkylphenol with CO by a homogeneous Pd-catalyst, and finally (iii) an oxidation of the 4-n-propylbenzoic acid to terephathalic acid by a Co-Mn-Br catalyst under O2 pressure. 
The demethoxylation was performed on crude lignin oil, which was obtained from corn stover by RCF in methanol over a Ru on carbon catalyst. 

The 4-n-alkylphenol yield after demethoxylation, starting from a guaiacyl and syringyl monomer mixture, was 65.7 mol% based on the total monomers (16.1 wt% based on lignin content). 
Interestingly, they found that the Mo catalyst also removed para-substituted ester group from phenolic monomers in addition to Terephthalic acid demethoxylation activity. 

Next, CO was inserted using carbonylation of 4-n-alkylphenols by a homogeneous Pd catalyst. 
To increase reactivity, 4-n-alkylphenol triflates were formed prior to carbonylation. 

On average, a 75 mol% yield was obtained for all 4-alkylphenols (methyl, ethyl and n-propyl) toward the 4-alkylbenzoic acid. 
Finally, the oxidation yield of 4-alkylbenzoic acid mixture toward terephthalic acid was 60 mol%. 

Remarkably, terephthalic acid could be obtained from the reaction mixture by simple filtration and washing with water. 
Looking at the overall process, the terephthalic acid yield starting from the lignin oil was 30 mol% and corresponds to 15.5 wt% based on corn stover lignin content.

Terephthalic acid is one isomer of the three phthalic acids. 
Terephthalic acid finds important use as a commodity chemical, principally as a starting compound for the manufacture of polyester (specifically PET), used in clothing and to make plastic bottles. 

Terephthalic acid is also known as 1,4-benzenedicarboxylic acid, and Terephthalic acid has the chemical formula C6H4(COOH)2. 
Terephthalic acid has recently become an important component in the development of hybrid framework materials.

Terephthalic acid is a benzenedicarboxylic acid carrying carboxy groups at positions 1 and 4. 
One of three possible isomers of benzenedicarboxylic acid, the others being phthalic and isophthalic acids. 

Terephthalic acid is a conjugate acid of a terephthalate(1-). 
Terephthalic acid is one isomer of the three phthalic acids. 

Terephthalic acid finds important use as a commodity chemical, principally as a starting compound for the manufacture of polyester (specifically PET), used in clothing and to make plastic bottles. 
Terephthalic acid is also known as 1,4-benzenedicarboxylic acid, and Terephthalic acid has the chemical formula C6H4(COOH)2.

Process for Preparation of Terephthalic Acid:
One of the world’s most widely produced polymers, poly(ethylene terephthalate) (PET), is synthesized via condensation polymerization of ethylene glycol with terephthalic acid and small amounts of isophthalic acid. 
Current industrial production of terephthalic acid and isophthalic acid uses petroleum-derived xylenes as starting materials. 

The cost and availability of petroleum varies wildly and unpredictably. 
In order to stabilize costs associated with the synthesis of terephthalic acid and isophthalic acid, alternative feedstocks must be made available. 

A reaction sequence has been elaborated that addresses this need. 
The starting materials, acrylic acid and isoprene, are reacted in a solvent-free cycloaddition catalyzed by an inexpensive Lewis acid catalyst. 

Vapor phase aromatization of the resulting cycloadducts affords para- and meta-toluic acid, which are oxidized to terephthalic acid and isophthalic acid, respectively. 
Both acrylic acid and isoprene are commercially synthesized from petroleum or shale gas but may also be synthesized from biobased feedstocks. 

Thus, by diversifying available feedstocks, costs associated with commercial terephthalic acid and isophthalic acid synthesis are stabilized. 
Moreover, this reaction sequence is the only one reported in the literature to produce both terephthalic acid and isophthalic acid for the manufacture of PET.

Biodegradation of Terephthalic acid:
In Comamonas thiooxydans strain E6, terephthalic acid is biodegraded by a pathway starting at terephthalate 1,2-dioxygenase into protocatechuic acid, a common natural product. 
Combined with the previously known PETase and MHETase, a full pathway for PET plastic degradation can be engineered.

Properties of Terephthalic acid:
Terephthalic acid is almost insoluble in water, alcohol and ether; Terephthalic acid sublimes rather than melting when heated. 
This insolubility makes Terephthalic acid relatively awkward to work with, and up until around 1970 much crude terephthalic acid was converted to the dimethyl ester for purification.

Production of Terephthalic acid:
Terephthalic acid can be formed in the laboratory by oxidizing para-diderivatives of benzene, or best by oxidizing caraway oil, a mixture of cymene and cuminol, with chromic acid.

On an industrial scale, terephthalic acid is produced, similar to benzoic acid, by oxidation of p-xylene by oxygen from air. 
This is done using acetic acid as solvent, in the presence of a catalyst such as cobalt-manganese, using a bromide promoter. 

Alternatively, Terephthalic acid can be made via the Henkel process, which involves the rearrangement of phthalic acid to terephthalic acid via the corresponding potassium salts. 
The terephthalic acid is and dimethyl terephthalate, in turn, often used as a monomer component in the production of polymers, principally polyethylene terephthalate (polyester or PET). 

World production in 1970 was around 1.75 million tonnes.
By 2006, global PTA demand had substantially exceeded 30 million tonnes.

Pharmacology and Biochemistry of Terephthalic acid:

MeSH Pharmacological Classification:

Free Radical Scavengers:
Substances that eliminate free radicals. 
Among other effects, they protect PANCREATIC ISLETS against damage by CYTOKINES and prevent myocardial and pulmonary REPERFUSION INJURY. 

Metabolism/Metabolites of Terephthalic acid:
A Rhodococcus species was isolated from soil by enriching for growth with dimethyl terephthalate as the sole carbon source.
The organism degraded dimethyl terephthalate by hydrolysis of ester-bonds to free terephthalic acid which in turn was metabolized through protocatechuate by an ortho-cleavage pathway

Biological Half-Life of Terephthalic acid:
The concentrations of urine terephthalic acid(TPA) in rats after single oral administration in dose of 100 mg/kg bw were determined by high pressure liquid chromatography.
The results showed that the first-order kinetics and two-compartment model were noted on the elimination of TPA. 
The main toxicokinetic parameters were as follows: Ka = 0.51/hr, half-life ka = 0.488 hr, half-life alpha = 2.446 hr, time to peak = 2.160 hr, Ku = 0.143/hr, half-life beta = 31.551 hr, Xu(max) = 10.00 mg.

The pharmacokinetics of (14)C labeled terephthalic acid were determined in Fischer 344 rats after iv and oral administration. 
After iv injection, the plasma concentration-time data were fitted using a 3-compartment pharmacokinetic model. 
The avg terminal half-life in rats was 1.2 hr and the average volume of distribution in the terminal phase was 1.3 L/kg.

Human Metabolite Information of Terephthalic acid:

Tissue Locations:
Fibroblasts
Platelet

Clinical Laboratory Methods of Terephthalic acid:
A procedure for the hydrolysis of phthalate esters and metabolites to free phthalic acid, recovery and esterification of the acid, and gas chromatographic quantification on 10% OV 25 on Gas Chroin Z all relative to an internal standard of 4-chlorophthalate was developed. 
The measurement limit is 0.5 nmol of total phthalate/mL of urine, and replicates. 

The assay is linear between 0.5 and 50 nmol/mL of urine, which spans of phthalate levels found thus far in human urine samples. 
The procedure can also be used to detect levels of isophthalate and terephthalate simultaneously with phthalate.

Synthesis of Terephthalic acid:

Amoco process:
In the Amoco process, which is widely adopted worldwide, terephthalic acid is produced by catalytic oxidation of p-xylene

The process uses a cobalt–manganese–bromide catalyst. 
The bromide source can be sodium bromide, hydrogen bromide or tetrabromoethane. 

Bromine functions as a regenerative source of free radicals. 
Acetic acid is the solvent and compressed air serves as the oxidant. 

The combination of bromine and acetic acid is highly corrosive, requiring specialized reactors, such as those lined with titanium. 
A mixture of p-xylene, acetic acid, the catalyst system, and compressed air is fed to a reactor.

Mechanism:
The oxidation of p-xylene proceed by a free radical process. 
Bromine radicals decompose cobalt and manganese hydroperoxides. 

The resulting oxygen-based radicals abstract hydrogen from a methyl group, which have weaker C–H bonds than does the aromatic ring. 
Many intermediates have been isolated. 

p-xylene is converted to p-toluic acid, which is less reactive than the p-xylene owing to the influence of the electron-withdrawing carboxylic acid group. 
Incomplete oxidation produces 4-carboxybenzaldehyde (4-CBA), which is often a problematic impurity.

Challenges:
Approximately 5% of the acetic acid solvent is lost by decomposition or "burning". 
Product loss by decarboxylation to benzoic acid is common. 

The high temperature diminishes oxygen solubility in an already oxygen-starved system. 
Pure oxygen cannot be used in the traditional system due to hazards of flammable organic–O2 mixtures. 

Atmospheric air can be used in Terephthalic acid place, but once reacted needs to be purified of toxins and ozone depleters such as methylbromide before being released. 
Additionally, the corrosive nature of bromides at high temperatures requires the reaction be run in expensive titanium reactors.

Alternative reaction media:
The use of carbon dioxide overcomes many of the problems with the original industrial process. 
Because CO2 is a better flame inhibitor than N2, a CO2 environment allows for the use of pure oxygen directly, instead of air, with reduced flammability hazards. 

The solubility of molecular oxygen in solution is also enhanced in the CO2 environment. 
Because more oxygen is available to the system, supercritical carbon dioxide (Tc = 31 °C) has more complete oxidation with fewer byproducts, lower carbon monoxide production, less decarboxylation and higher purity than the commercial process.

In supercritical water medium, the oxidation can be effectively catalyzed by MnBr2 with pure O2 in a medium-high temperature. 
Use of supercritical water instead of acetic acid as a solvent diminishes environmental impact and offers a cost advantage. 
However, the scope of such reaction systems is limited by the even harsher conditions than the industrial process (300−400 °C, >200 bar).

Promotors and additives:
As with any large-scale process, many additives have been investigated for potential beneficial effects. 
Promising results have been reported with the following.

Ketones act as promoters for formation of the active cobalt(III) catalyst. 
In particular, ketones with a-methylene groups oxidize to hydroperoxides that are known to oxidize cobalt(II). 

Butanone is often used.
Zirconium salts enhance the activity of Co-Mn-Br catalysts. 

Selectivity is also improved.
N-Hydroxyphthalimide is a potential replacement for bromide, which is highly corrosive. 

The phthalimide functions by formation of the oxyl radical.
Guanidine inhibits the oxidation of the first methyl but enhances the usually slow oxidation of the toluic acid.

Alternative routes:
Terephthalic acid can be prepared in the laboratory by oxidizing many para-disubstituted derivatives of benzene, including caraway oil or a mixture of cymene and cuminol with chromic acid.

Although not commercially significant is the so-called "Henkel process" or "Raecke process", named after the company and patent holder, respectively. 
This process involves the transfer of carboxylate groups. 
For example potassium benzoate disproportionates to potassium terephthalate and potassium phthalate rearranges to potassium terephthalate.

Lummus (now a subsidiary of McDermott International) has reported a route from the dinitrile, which can be obtained by ammoxidation of p-xylene.

Uses of Terephthalic acid:
Used in wool processing and making plastic films and sheets.
Also added to poultry feeds and to certain antibiotics to increase their effectiveness.

Industrial Processes with risk of exposure:
Textiles (Fiber & Fabric Manufacturing)
Farming (Feed Additives)

Terephthalic acid is used almost exclusively to produce saturated polyesters.
Production of linear, crystalline polyester resins, fibers, and films by combination with glycols; reagent for alkali in wool; additive to poultry feeds.

Forms polyesters with glycols which are made into plastic films & sheets; used in analytical chemistry.
Terephthalic acid is an intermediate in the production of oligomeric terephthalic acid esters.

Plasticizer component

Industry Uses of Terephthalic acid:
Adhesives and sealant chemicals
Intermediates
Investment casting waxes
Lubricants and lubricant additives
Paint additives and coating additives not described by other categories
Plasticizers
Reactant in polymerization process
Solvents (which become part of product formulation or mixture)
monomer for polyester based composites
polyester for composite manufacture
polyester for composite part manufacture

Consumer Uses of Terephthalic acid:
Building/construction materials not covered elsewhere
Food packaging
Intermediates
Investment casting waxes.
Paints and coatings
Plastic and rubber products not covered elsewhere

Methods of Manufacturing of Terephthalic acid:
p-Xylene is the feedstock for all terephthalic acid production.
Oxidation catalysts and conditions have been developed which give nearly quantitative oxidation of the methyl groups, leaving the benzene ring virtually untouched. 

These catalysts are combinations of cobalt, manganese, and bromine, or cobalt with a co-oxidant, e.g., acetaldehyde. 
Oxygen is the oxidant in all processes. 

Acetic acid is the reaction solvent in all but one process. 
Given these constant factors, there is only one industrial oxidation process, with different variations, two separate purification processes, and one process which intermixes oxidation and esterification steps.

Produced commercially primarily by the Amoco process. 
Inhibition of the oxidation of the second methyl group of p-xylene is suppressed with the aid of added bromine-containing promoters as cocatalysts.
The oxidation takes place in air and produces raw terephthalic acid, which is dissolved at high temperature under pressure in water, hydrated, and thus purified.

Prepared by oxidation of p-methylacetophenone.

(1) Oxidation of para-xylene or of mixed xylenes and other alkyl aromatics (phthalic anhydride); (2) reacting benzene and potassium carbonate over a cadmium catalyst.
Reacting carbon monoxide or methanol with toluene to form various intermediates which, upon oxidation, form terephthalic acid.

General Manufacturing Information of Terephthalic acid:

Industry Processing Sectors:
Adhesive manufacturing
All other basic organic chemical manufacturing
All other chemical product and preparation manufacturing
Construction
Paint and coating manufacturing
Plastic material and resin manufacturing
Plastics product manufacturing
Textiles, apparel, and leather manufacturing

Applications of Terephthalic acid:
Terephthalic acid (TPA) can be synthesized from bio-based materials for a variety of applications, which include the production of polyester fiber, non-fiber field, PET bottles, synthetic perfumes and medicines.
Terephthalic acid is used as a linker molecule in the preparation of metal organic frameworks (MOFs).

Virtually the entire world's supply of terephthalic acid and dimethyl terephthalate are consumed as precursors to polyethylene terephthalate (PET). 
World production in 1970 was around 1.75 million tonnes.

By 2006, global purified terephthalic acid (PTA) demand had exceeded 30 million tonnes. 
A smaller, but nevertheless significant, demand for terephthalic acid exists in the production of polybutylene terephthalate and several other engineering polymers.

Other uses of Terephthalic acid:
Polyester fibers based on PTA provide easy fabric care, both alone and in blends with natural and other synthetic fibers. 
Polyester films are used widely in audio and video recording tapes, data storage tapes, photographic films, labels and other sheet material requiring both dimensional stability and toughness.

Terephthalic acid is used in paint as a carrier.
Terephthalic acid is used as a raw material to make terephthalate plasticizers such as dioctyl terephthalate and dibutyl terephthalate.

Terephthalic acid is used in the pharmaceutical industry as a raw material for certain drugs.
In addition to these end uses, Terephthalic acid based polyesters and polyamides are also used in hot melt adhesives.

PTA is an important raw material for lower molecular weight saturated polyesters for powder and water-soluble coatings.
In the research laboratory, terephthalic acid has been popularized as a component for the synthesis of metal-organic frameworks.

The analgesic drug oxycodone occasionally comes as a terephthalate salt; however, the more usual salt of oxycodone is the hydrochloride. 
Pharmacologically, one milligram of terephthalas oxycodonae is equivalent to 1.13 mg of hydrochloridum oxycodonae.
Terephthalic acid is used as a filler in some military smoke grenades, most notably the American M83 smoke grenade and M90 vehicle-employed smoke grenade, producing a thick white smoke that acts as an obscurant in the visual and near-infrared spectrum when burned.

History of Terephthalic acid:
Terephthalic acid was first isolated (from turpentine) by the French chemist Amédée Cailliot (1805–1884) in 1846.
Terephthalic acid became industrially important after World War II. 

Terephthalic acid was produced by oxidation of p-xylene with dilute nitric acid. 
Air oxidation of p-xylene gives p-toluic acid, which resists further air-oxidation. 

Conversion of p-toluic acid to methyl p-toluate (CH3C6H4CO2CH3) opens the way for further oxidation to monomethyl terephthalate, which is further esterified to dimethyl terephthalate. 
In 1955, Mid-Century Corporation and ICI announced the bromide-promoted oxidation of p-toluic acid to teraphthalic acid. 

This innovation enabled the conversion of p-xylene to terephthalic acid without the need to isolate intermediates. 
Amoco (as Standard Oil of Indiana) purchased the Mid-Century/ICI technology.

Reactivity Profile of Terephthalic acid:
TEREPHTHALIC ACID is a carboxylic acid. 
Terephthalic acid donates hydrogen ions if a base is present to accept them. 

This "neutralization" generates substantial amounts of heat and produces water plus a salt. 
Insoluble in water but even "insoluble" carboxylic acids may absorb enough water from the air and dissolve sufficiently in Terephthalic acid to corrode or dissolve iron, steel, and aluminum parts and containers. 

May react with cyanide salts to generate gaseous hydrogen cyanide. 
Will react with solutions of cyanides to cause the release of gaseous hydrogen cyanide. 

Flammable and/or toxic gases and heat are generated by reaction with diazo compounds, dithiocarbamates, isocyanates, mercaptans, nitrides, and sulfides. 
React with sulfites, nitrites, thiosulfates (to give H2S and SO3), dithionites (SO2), to generate flammable and/or toxic gases and heat. 

Reaction with carbonates and bicarbonates generates a harmless gas (carbon dioxide) but still heat. 
Can be oxidized by strong oxidizing agents and reduced by strong reducing agents. 

These reactions generate heat. 
May initiate polymerization reactions; may catalyze (increase the rate of) chemical reactions.

Handling and Storage of Terephthalic acid:

Nonfire Spill Response:
SMALL SPILLS AND LEAKAGE: Should a spill occur while you are handling this chemical, FIRST REMOVE ALL SOURCES OF IGNITION, then you should dampen the solid spill material with ethanol and transfer the dampened material to a suitable container. 
Use absorbent paper dampened with ethanol to pick up any remaining material. 

Seal the absorbent paper, and any of your clothes, which may be contaminated, in a vapor-tight plastic bag for eventual disposal. 
Solvent wash all contaminated surfaces with ethanol followed by washing with a soap and water solution. 
Do not reenter the contaminated area until the Safety Officer (or other responsible person) has verified that the area has been properly cleaned. 

STORAGE PRECAUTIONS: You should store this material in a refrigerator.

Safe Storage of Terephthalic acid:
Separated from strong oxidants.

Storage Conditions of Terephthalic acid:
Store in detached units of noncombustible construction.

Regulatory Information of Terephthalic acid:

Atmospheric Standards of Terephthalic acid:
This action promulgates standards of performance for equipment leaks of Volatile Organic Compounds (VOC) in the Synthetic Organic Chemical Manufacturing Industry (SOCMI). 
The intended effect of these standards is to require all newly constructed, modified, and reconstructed SOCMI process units to use the best demonstrated system of continuous emission reduction for equipment leaks of VOC, considering costs, non air quality health and environmental impact and energy requirements. 
Terephthalic acid is produced, as an intermediate or a final product, by process units covered under this subpart.

First Aid of Terephthalic acid:
EYES: First check the victim for contact lenses and remove if present. 
Flush victim's eyes with water or normal saline solution for 20 to 30 minutes while simultaneously calling a hospital or poison control center. 

Do not put any ointments, oils, or medication in the victim's eyes without specific instructions from a physician. 
IMMEDIATELY transport the victim after flushing eyes to a hospital even if no symptoms (such as redness or irritation) develop. 

SKIN: IMMEDIATELY flood affected skin with water while removing and isolating all contaminated clothing. 
Gently wash all affected skin areas thoroughly with soap and water. 
If symptoms such as redness or irritation develop, IMMEDIATELY call a physician and be prepared to transport the victim to a hospital for treatment. 

INHALATION: IMMEDIATELY leave the contaminated area; take deep breaths of fresh air. 
If symptoms (such as wheezing, coughing, shortness of breath, or burning in the mouth, throat, or chest) develop, call a physician and be prepared to transport the victim to a hospital. 

Provide proper respiratory protection to rescuers entering an unknown atmosphere. 
Whenever possible, Self-Contained Breathing Apparatus (SCBA) should be used; if not available, use a level of protection greater than or equal to that advised under Protective Clothing. 

INGESTION: DO NOT INDUCE VOMITING. 
If the victim is conscious and not convulsing, give 1 or 2 glasses of water to dilute the chemical and IMMEDIATELY call a hospital or poison control center. 

Be prepared to transport the victim to a hospital if advised by a physician. 
If the victim is convulsing or unconscious, do not give anything by mouth, ensure that the victim's airway is open and lay the victim on his/her side with the head lower than the body. 

DO NOT INDUCE VOMITING. 
IMMEDIATELY transport the victim to a hospital.

Fire Fighting of Terephthalic acid:
Fires involving this material can be controlled with a dry chemical, carbon dioxide or Halon extinguisher.

Accidental Release Measures of Terephthalic acid:

Spillage Disposal of Terephthalic acid:    
Personal protection: particulate filter respirator adapted to the airborne concentration of the substance. 
Sweep spilled substance into covered containers. 

If appropriate, moisten first to prevent dusting. 
Carefully collect remainder. 
Then store and dispose of according to local regulations.

Cleanup Methods of Terephthalic acid:
Remove all ignition sources. 
Collect powdered material in the most convenient and safe manner and deposit in sealed containers. 
Ventilate area after clean up is complete.

Disposal Methods of Terephthalic acid:
The most favorable course of action is to use an alternative chemical product with less inherent propensity for occupational harm/injury/toxicity or environmental contamination. 
Recycle any unused portion of the material for Terephthalic acid approved use or return Terephthalic acid to the manufacturer or supplier. 

After material has been contained, scoop up contaminated soil and place in impervious containers. 
Material may be disposed of in an approved chemical incinerator. 

If facilities are not available, material may be disposed of in an approved waste chemical landfill. 
When dilute, amenable to biological treatment at a municipal sewage treatment plant.

Preventive Measures of Terephthalic acid:
The scientific literature for the use of contact lenses by industrial workers is inconsistent. 
The benefits or detrimental effects of wearing contact lenses depend not only upon the substance, but also on factors including the form of the substance, characteristics and duration of the exposure, the uses of other eye protection equipment, and the hygiene of the lenses. 

However, there may be individual substances whose irritating or corrosive properties are such that the wearing of contact lenses would be harmful to the eye. 
In those specific cases, contact lenses should not be worn. 
In any event, the usual eye protection equipment should be worn even when contact lenses are in place.

Contaminated protective clothing should be segregated in such a manner so that there is no direct personal contact by personnel who handle, dispose, or clean the clothing. 
Quality assurance to ascertain the completeness of the cleaning procedures should be implemented before the decontaminated protective clothing is returned for reuse by the workers. 
Contaminated clothing should not be taken home at end of shift, but should remain at employee's place of work for cleaning.

Identifiers of Terephthalic acid:
CAS Number: 100-21-0
3DMet: B00943
Beilstein Reference: 1909333
ChEBI: CHEBI:15702
ChEMBL: ChEMBL1374420
ChemSpider: 7208
ECHA InfoCard: 100.002.573
EC Number: 202-830-0
Gmelin Reference: 50561
KEGG: C06337
PubChem CID: 7489
RTECS number: WZ0875000
UNII: 6S7NKZ40BQ
CompTox Dashboard (EPA): DTXSID6026080
InChI:
InChI=1S/C8H6O4/c9-7(10)5-1-2-6(4-3-5)8(11)12/h1-4H,(H,9,10)(H,11,12) check
Key: KKEYFWRCBNTPAC-UHFFFAOYSA-N check
InChI=1/C8H6O4/c9-7(10)5-1-2-6(4-3-5)8(11)12/h1-4H,(H,9,10)(H,11,12)
Key: KKEYFWRCBNTPAC-UHFFFAOYAF
SMILES: O=C(O)c1ccc(C(O)=O)cc1

Properties of Terephthalic acid:
Chemical formula: C8H6O4
Molar mass: 166.132 g·mol−1
Appearance: White crystals or powder
Density: 1.522 g/cm3
Melting point: 427 °C (801 °F; 700 K) in a sealed tube. Sublimes at standard atmospheric pressure.
Boiling point: Decomposes
Solubility in water: 0.0015 g/100 mL at 20 °C
Solubility: polar organic solvents aqueous base
Acidity (pKa): 3.51, 4.82
Magnetic susceptibility (χ): −83.51×10−6 cm3/mol

Molecular Weight: 166.13
XLogP3: 2
Hydrogen Bond Donor Count: 2
Hydrogen Bond Acceptor Count: 4
Rotatable Bond Count: 2
Exact Mass: 166.02660867
Monoisotopic Mass: 166.02660867
Topological Polar Surface Area: 74.6 Ų
Heavy Atom Count    : 12
Complexity: 169
Isotope Atom Count: 0
Defined Atom Stereocenter Count: 0
Undefined Atom Stereocenter Count: 0
Defined Bond Stereocenter Count: 0
Undefined Bond Stereocenter Count: 0
Covalently-Bonded Unit Count: 1
Compound Is Canonicalized: Yes

Vapor pressure: <0.01 mmHg ( 20 °C)
Quality Level: 100
Assay: 98%
Form: powder
Autoignition temp.: 925 °F
mp: >300 °C (lit.)
Solubility: water: ~0.017 g/L at 25 °C
Density: 1.58 g/cm3 at 25 °C
Greener alternative category: Enabling
SMILES string: OC(=O)c1ccc(cc1)C(O)=O
InChI: 1S/C8H6O4/c9-7(10)5-1-2-6(4-3-5)8(11)12/h1-4H,(H,9,10)(H,11,12)
InChI key: KKEYFWRCBNTPAC-UHFFFAOYSA-N

Structure of Terephthalic acid:
Dipole moment: 2.6D

Thermochemistry of Terephthalic acid:
Std enthalpy of formation (ΔfH⦵298): 232 kJ/m

Related compounds of Terephthalic acid:
p-Xylene
Polyethylene terephthalate
Dimethyl terephthalate

Related carboxylic acids:
Phthalic acid
Isophthalic acid
Benzoic acid
p-Toluic acid

Names of Terephthalic acid:

Preferred IUPAC name of Terephthalic acid:
Benzene-1,4-dicarboxylic acid

Other names of Terephthalic acid:
Terephthalic acid
para-Phthalic acid
TPA
PTA
BDC

Synonyms of Terephthalic acid:
TEREPHTHALIC ACID
100-21-0
p-Phthalic acid
1,4-Benzenedicarboxylic acid
benzene-1,4-dicarboxylic acid
p-Dicarboxybenzene
p-Benzenedicarboxylic acid
p-Carboxybenzoic acid
Acide terephtalique
1,4-dicarboxybenzene
Kyselina tereftalova
WR 16262
TA-33MP
NSC 36973
HSDB 834
p-Phthalate
TA 12
UNII-6S7NKZ40BQ
Kyselina terftalova
Benzene-p-dicarboxylic acid
6S7NKZ40BQ
CHEBI:15702
MFCD00002558
para-Phthalic acid
Tephthol
DSSTox_CID_6080
DSSTox_RID_78007
DSSTox_GSID_26080
Acide terephtalique
Kyselina tereftalova
CAS-100-21-0
CCRIS 2786
4-Carboxybenzoic Acid
EINECS 202-830-0
BRN 1909333
terephtalic acid
AI3-16108
P-Phthelate
P-Phthelic acid
UB7
p-Benzenedicarboxylate
terephthals&#xe4;ure
Benzene-p-dicarboxylate
benzene-1,4-dioic acid
WLN: QVR DVQ
Terephthalic acid, 97%
Terephthalic acid, 98%
EC 202-830-0
SCHEMBL1655
para-benzenedicarboxylic acid
Benzene, p-dicarboxylic acid
4-09-00-03301 (Beilstein Handbook Reference)
BIDD:ER0245
tere-Phthalic Acid (Sublimed)
CHEMBL1374420
DTXSID6026080
Benzene, 1,4-Dicarboxylic acid
p-Dicarboxybenzene p-Phthalic acid
BCP06429
NSC36973
STR02759
Tox21_201659
Tox21_303229
NSC-36973
s6251
STL281856
ZINC12358714
Terephthalic acid, analytical standard
AKOS000119464
CS-W010814
HY-W010098
MCULE-9289682931
NCGC00091618-01
NCGC00091618-02
NCGC00091618-03
NCGC00257014-01
NCGC00259208-01
AC-10250
BP-21157
FT-0674866
FT-0773240
T0166
C06337
Terephthalic acid, SAJ special grade, >=98.0%
A852800
AE-562/40217759
Q408984
Terephthalic acid, Vetec(TM) reagent grade, 98%
Z57127536
Kyselina terftalova, RARECHEM AL BO 0011, 1,4-phthalicacid
Ecamsule Related Compound C, United States Pharmacopeia (USP) Reference Standard

  • Share !
E-NEWSLETTER