Xylen Tổng hợp hữu cơ hóa dầu

PowerPoint Presentation TOÅNG HÔÏP HÖÕU CÔ & HOÙA DAÀU GV ÑAØO THÒ KIM THOA Boä moân CNCB Daàu khí, Khoa CNHH, ÑH Baùch Khoa Tp HCM * BAØI 9 HOÙA HOÏC TREÂN CÔ SÔÛ XYLENE The term xylenes refers to a[.]

TỔNG HỢP HỮU CƠ &

HÓA DẦU

GV: ĐÀO THỊ KIM THOA Bộ môn CNCB Dầu khí, Khoa CNHH, ĐH Bách

Khoa Tp HCM

BÀI 9: HÓA HỌC TRÊN CƠ SỞ XYLENE

The term xylenes refers to a group of 3 benzene derivatives which

encompasses ortho-, meta-, and para- isomers of dimethyl benzene

The o-, m- and p- isomers specify to which carbon atoms (of the main

benzene ring) the two methyl groups are attached Counting the carbon atoms from one of the ring carbons bonded to a methyl group, and counting towards the second ring carbon bonded to a

methyl group, the o- isomer has the IUPAC name of

1,2-dimethylbenzene The m- isomer has the IUPAC name of 1,3-dimethylbenzene And p- isomer has the IUPAC name of

1,4-dimethylbenzene

I Giới thiệu:

 Xylenes: dimethyl benzene.

 Nguồn: reforming xt, cracking.

 P- xylene: quan trọng nhất: tạo terephthalic

acid để tổng hợp polyester.

 M – xylene: ít được dùng nhất: nhưng lại

chiếm tỷ lệ cao nhất trong hỗn hợp, thường được isomer hóa thành p-xylene.

 Hóa học chủ yếu trên nhóm thế methyl,

phản ứng oxy hóa.

 65% xylenes dùng để tổn hợp hóa chất.

 Phần còn lại: làm dung môi hay pha trộn

xăng.

It is a colorless, sweet-smelling liquid that is very flammable It occurs naturally in petroleum and coal tar

and is formed during forest fires The chemical properties differ slightly from isomer to isomer The melting point is

between −47.87 °C (m-xylene) and 13.26 °C (p-xylene)

The boiling point is for each isomer at around 140 °C The density is at around 0.87 kg/L and thus is less dense than water Xylene in air can be smelled at 0.08 to 3.7 parts of xylene per million parts of air (ppm) and can begin to be tasted in water at 0.53 to 1.8 ppm.

Terephthalic acid is one isomer of the three phthalic acids It 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 It is also

known as 1,4-benzenedicarboxylic acid, and it has the

chemical formula C6H4(COOH)2

II Hóa học trên cơ sở xylenes:

1 Terephthalic acid (HOOC-C6H4 -COOH ) (TPA)

Ứng dụng chính của TPAvà DMT: tổng hợp polyester để sx sợi tổng hợp và film

COOH

CH3 + 3 O2 + 2CH3-OH CH3OOC COO-CH3 + 4H2O

COO-CH3

CH3OOC + 2H2O COOH COOH + 2 CH3-OH

CH3

Dimethyl terephthalate (DMT)

It is almost insoluble in water, alcohol and ether; it sublimes rather than melting when heated This insolubility makes it relatively awkward to work with, and up until around

1970 much crude terephthalic acid was converted to the dimethyl ester for purification

Phthalic anhydride

phthalic acid It dissolves in alcohol and some other organic solvents

Phthalic anhydride is obtained either by catalytic oxidation of ortho-xylene with O2 (oxygen) or by catalytic oxidation of

naphthalene The biproducts of the napthalene reaction are carbon dioxide and water

It is hydrolyzed by hot water, forming

ortho-phthalic acid.

Phthalic anhydride is widely used in industry in the production of dyes (rhodamine, anthraquinone derivatives), insecticides, plasticizers, in pharmacy, in analytic chemistry, etc

Hiện nay, phthalic anhydride chủ yếu đi từ con đường oxy hóa o-xylene

P: 0.7 atm

Hs: 85% phthalic anhydride

Phản ứng pha hơi

Ứng dụng: sx chất hoá dẻo, nhựa polyester không no, nhựa alkyd.

CH3

C O

O

O