95-63-6 Usage
Description
1,2,4-Trimethylbenzene (mesitylene) is an aromatic hydrocarbon compound commonly present in commercial solvents encompassing their boiling range. Mesitylene are the most common isomer used in commercial applications. Aromatic hydrocarbons in hydrocarbon solvents are predominantly alkylated one ring structures as well as two aromatic ring structures which may also be alkylated.
Toxicity
Acute toxicity studies (oral, dermal and inhalation routes of exposure) have been conducted in rats. Oral LD50 values of greater than 5000 mg/kg have been reported. For solvent products containing predominantly mixed C9 aromatic hydrocarbons, oral LD50 values have been reported as greater than 6880 mg/kg (males) and greater than 3440 mg/kg (females). LC50 values of 18,000 mg/m3 was reported for 1,2,4-TMB. For C9 aromatic solvents, the LC50 was greater than 10,200 mg/m3 (Shell Research Laboratory, 1976, unpublished study). One dermal acute study showed an LD50 value of greater than 3440 mg/kg for a C9 aromatic solvent (Shellsol A, a highly aromatic solvent boiling in the white spirit range, consisting of primarily C9 isomers particularly TMBs)
Chemical Properties
colourless liquid
Physical properties
Colorless liquid with a slight aromatic odor. A detection odor threshold concentration of 12 mg/m3
(2.4 ppmv) was experimentally determined by Dravnieks (1974).
Uses
Different sources of media describe the Uses of 95-63-6 differently. You can refer to the following data:
1. 1,2,4-Trimethylbenzene is the unlabelled version of 1,2,4-Trimethyl 13C6-benzene (T796173), a labelled aromatic standard.
2. Sterilizing catgut by heating one hour at 160°; solvent in manufacture of dyes, perfumes and resins. Solvent for liquid scintillation counting solutions.
Definition
ChEBI: A trimethylbenzene carrying methyl groups at positions 1, 2 and 4.
Synthesis Reference(s)
Journal of the American Chemical Society, 73, p. 766, 1951 DOI: 10.1021/ja01146a079Chemical and Pharmaceutical Bulletin, 34, p. 540, 1986 DOI: 10.1248/cpb.34.540
General Description
A liquid. Flash point near 130°F. Less dense than water and insoluble in water. Vapors irritate eyes, throat, and nose. Used in dyes and pharmaceuticals.
Air & Water Reactions
Insoluble in water.
Reactivity Profile
1,2,4-Trimethylbenzene is incompatible with the following: Oxidizers, nitric acid .
Hazard
Moderate fire risk. Central nervous system
depressant, irritant to mucous membranes. Asthma
and hematologic effects.
Health Hazard
Harmful if inhaled or swallowed. Vapor or mist is irritating to the eyes, mucous membrane and upper respiratory tract. Prolonged contact can cause dermatitis, nausea, headache, dizziness, and narcotic effect.
Safety Profile
Moderately toxic by
intraperitoneal route. Mildly toxic by
inhalation. Can cause central nervous system
depression, anemia, bronchitis. Flammable
liquid when exposed to heat, sparks, or
flame. To fight fire, use foam, alcohol foam,
mist. Emitted from modern building
materials (CENEAR 69,22,91). When
heated to decomposition it emits acrid
smoke and irritating fumes.
Source
Detected in distilled water-soluble fractions of 87 octane gasoline (1.11 mg/L), 94 octane
gasoline (3.11 mg/L), Gasohol (2.90 mg/L), No. 2 fuel oil (0.51 mg/L), jet fuel A (0.44 mg/L),
diesel fuel (0.39 mg/L), and military jet fuel JP-4 (0.39 mg/L) (Potter, 1996). Schauer et al. (1999)
reported 1,2,4-trimethylbenzene in a diesel-powered medium-duty truck exhaust at an emission
rate of 880 μg/km.
California Phase II reformulated gasoline contained 1,2,4-trimethylbenzene at a concentration of
24.6 g/kg. Gas-phase tailpipe emission rates from gasoline-powered automobiles with and without
catalytic converters were 5.72 and 602 mg/km, respectively (Schauer et al., 2002).
Thomas and Delfino (1991) equilibrated contaminant-free groundwater collected from
Gainesville, FL with individual fractions of three individual petroleum products at 24–25 °C for
24 h. The aqueous phase was analyzed for organic compounds via U.S. EPA approved test method
602. Average 1,2,4-trimethylbenzene concentrations reported in water-soluble fractions of
unleaded gasoline, kerosene, and diesel fuel were 1.952, 0.478, and 0.130 mg/L, respectively.
When the authors analyzed the aqueous-phase via U.S. EPA approved test method 610, average
1,2,4-trimethylbenzene concentrations in water-soluble fractions of unleaded gasoline, kerosene,
and diesel fuel were generally greater, i.e., 1.968, 0.401, and 0.146 mg/L, respectively.
Drinking water standard: No MCLGs or MCLs have been proposed (U.S. EPA, 2000).
Environmental fate
Biological. In anoxic groundwater near Bemidji, MI, 1,2,4-trimethylbenzene anaerobically
biodegraded to the intermediate 3,4-dimethylbenzoic acid and the tentatively identified
compounds 2,4- and/or 2,5-dimethylbenzoic acid (Cozzarelli et al., 1990).
Photolytic. Glyoxal, methylglyoxal, and biacetyl were produced from the photooxidation of
1,2,4-trimethylbenzene by OH radicals in air at 25 °C (Tuazon et al., 1986a). A rate constant of
2.0 x 10-8 L/molecule?sec was reported for the reaction of 1,2,4-trimethylbenzene with OH radicals
in the gas phase (Darnall et al., 1976). Similarly, the rate constants for the reaction of 1,2,4-
trimethylbenzene and OH radicals at room temperature were 3.35 x 10-11 (Hansen et al., 1975) and
3.84 x 10-11 cm3/molecule?sec (Atkinson, 1985). At 25 °C, a rate constant of 3.15 x 10-11
cm3/molecule?sec was reported for the same reaction (Ohta and Ohyama, 1985). Products
identified from the OH radical-initiated reaction of 1,2,4-trimethylbenzene in the presence of
nitrogen dioxide were 3-hexene-2,5-dione and 2,3-butanedione (Bethel et al., 2000).
Chemical/Physical. 1,2,4-Trimethylbenzene will not hydrolyze in water (Kollig, 1993).
Purification Methods
Reflux pseudocumene over sodium and distil it under reduced pressure. [Beilstein 6 H 1088, 6 I 542, 6 II 1072, 6 III 6278, 6 IV 7339.]
Check Digit Verification of cas no
The CAS Registry Mumber 95-63-6 includes 5 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 2 digits, 9 and 5 respectively; the second part has 2 digits, 6 and 3 respectively.
Calculate Digit Verification of CAS Registry Number 95-63:
(4*9)+(3*5)+(2*6)+(1*3)=66
66 % 10 = 6
So 95-63-6 is a valid CAS Registry Number.
InChI:InChI=1/C9H12/c1-7-4-5-8(2)9(3)6-7/h4-6H,1-3H3
95-63-6Relevant articles and documents
Centrifugation-free and high yield synthesis of nanosized H-ZSM-5 and its structure-guided aromatization of methanol to 1,2,4-trimethylbenzene
Shen, Kui,Qian, Weizhong,Wang, Ning,Su, Chang,Wei, Fei
, p. 19797 - 19808 (2014)
Nanosized H-ZSM-5 has been proven to be an efficient way to improve mass transport properties with shape selectivity in many catalytic reactions. Generally, the synthesis of very fine nanosized H-ZSM-5 always suffers from low product yield and requires a complicated centrifugal separation process, both of which severely hinder its large-scale preparation and industrial applications. Herein, we report a centrifugation-free and high yield synthesis route for hierarchically nanosized ZSM-5 with a wide Si/Al ratio range by a combination of pre-aging process and steam-assisted conversion method using alkalis-free powder as the ZSM-5 precursor. This facile route not only avoids the energy-intensive centrifugal separation and ion-exchange process, but also significantly increases the crystallization efficiency along with a high yield. The obtained nanosized ZSM-5 possesses an ultrafine uniform size, high surface area, high total pore volumes, tunable Si/Al molar ratio, and high crystallinity. As a result, the nanosized ZSM-5 shows excellent catalytic performance when used in the catalytic conversion of methanol to aromatics. Notably, the nanosized ZSM-5 with a Si/Alth of 60 (NZS-60) shows an almost 25-fold longer catalytic lifetime, as well as up to 16% higher total aromatic selectivity when compared with conventional ZSM-5. Furthermore, the selectivity of 1,2,4-trimethylbenzene over this catalyst can be up to 44% in all products and 64% in aromatics products. Characterization results of the spent samples reveal that the most-improved catalytic performance and high selectivity of 1,2,4-trimethylbenzene over the nanosized ZSM-5 could be attributed to its small crystal size and hierarchical structure, which not only prevents the deposition of polyaromatic hydrocarbon in the microspores, but also sharply increases the reaction efficiency of bulky intermediate products on the surface of the catalyst.
Probing the pore structure of hierarchical EU-1 zeolites by adsorption of large molecules and through catalytic reaction
Guo, Zaibin,Hao, Wenming,Ma, Jinghong,Li, Ruifeng
, p. 187 - 193 (2020/07/04)
The adsorption of toluene and 1,3,5-trimethylbenzene and the catalytic transformation of 1,3,5-trimethylbenzene are applied as probing approaches to characterize the pore system of hierarchical EU-1 zeolites prepared using organofunctionalized fumed silica as the silicon source. The adsorption and diffusion of toluene and 1,3,5-trimethylbenzene are significantly improved in the hierarchical EU-1 zeolites compared with the conventional microporous EU-1 zeolite. The adsorption kinetics of toluene and 1,3,5-trimethylbenzene suggested that introducing mesopores significantly increases the rate of adsorption and improved the diffusion of large molecules. In the catalytic transformation of 1,3,5-trimethylbenzene, the conversion of 1,3,5-trimethylbenzene on the hierarchical EU-1 zeolites is doubled compared with the conventional microporous EU-1 zeolite, due to the improved diffusion of bulky molecules and enhanced accessibility of active sites in the hierarchical EU-1 structure. Although isomerization is the main reaction, differences are observed in the product ratios of isomerization to disproportionation between the hierarchical EU-1 zeolites and the microporous counterpart with different times on stream. The transformation of 1,3,5-trimethylbenzene over the hierarchical EU-1 zeolites has a higher isomerization to disproportionation ratio than that over the microporous EU-1 zeolite; this is due to the increased mesoporosity.
PROCESS FOR CO-PRODUCTION OF MIXED XYLENES AND HIGH OCTANE C9+ AROMATICS
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Paragraph 0067-0072, (2019/10/23)
Disclosed is a process for producing mixed xylenes and C9+ hydrocarbons in which an aromatic hydrocarbon feedstock comprising benzene and/or toluene is contacted with an alkylating agent comprising methanol and/or dimethyl ether under alkylation conditions in the presence of an alkylation catalyst to produce an alkylated aromatic product stream comprising the mixed xylenes and C9+ hydrocarbons. The mixed xylenes are subsequently converted to para-xylene, and the C9+ hydrocarbons and its components may be supplied as motor fuels blending components. The alkylation catalyst comprises a molecular sieve having a Constraint Index in the range from greater than zero up to about 3. The molar ratio of aromatic hydrocarbon to alkylating agent is in the range of greater than 1:1 to less than 4:1.