Newsgroup: it.scienza.chimica
Titolo: Ho un disperato bisogno di aiuto!!!!!!!!!!!

Ciao a tutti,
 sto svolgendo la tesina di fine anno (faccio la V° chimica) e mi serve
l'impianto di produzione del DDT. In internet non riesco a trovare niente!
qualcuno di voi ha per caso l'impianto disegnato oppure sa dove posso
reperirlo oppure sa il meccanismo industriale così dopo l'impianto lo faccio
io? grazie mille a tutti coloro che mi saranno di aiuto!!!!
andrea

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Puoi provare ad andare su 
it.espacenet.com
 e cercare dei brevetti
relativi.
Tex
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la mia enciclopedia dice tutto.....
ovviamente l'impianto non c'è ma con un po di fantasia non è difficile
immaginarne il reattore del tipo BATCH agitato e incamiciato
a questo punto la parte di purificazione è tutta da inventare sulla base
delle proprietà chimico-fisiche della miscela
materie prime
-2,2,2-trichloroethanal
sostanzialmente il 2,2,2-trichloroethanal lo ottieni come sottoprodotto
dall'ossiclorurazione di etilene oppure dalla clorurazione di
etanolo/acetaldeide
-chlorobenzene
clorurazione del benzene in presenza di un acido di lewis
Although DDT was synthesized by O. ZEIDLER in 1874, its insecticidal
properties were discovered by P. MÜLLER in 1939 [51]. This discovery marked
the beginning of the era of synthetic organic insecticides. Because DDT
appeared at the onset of World War II, it rapidly became the standard remedy
for control of typhus and malaria in both military and civilian use. At its
peak use in 1962, about 85×106 kg of DDT was produced in the United States.
The compound has an appropriate combination of properties: (1) broad
spectrum of insecticidal activity, (2) long residual persistence, (3) low
acute toxicity to mammals, and (4) low cost. The enormous publicity it
received after World War II heightened its use as a panacea for all insect
pest control problems, and DDT quickly became the standard remedy for
control of the codling moth on deciduous fruit, the pink bollworm on cotton,
the Colorado potato beetle, and the European corn borer. During the 1960s,
DDT was registered for use on 334 agricultural commodities in the United
States. It was highly effective against forest defoliators such as the gypsy
moth and the spruce budworm and as a home mothproofing agent. The safety and
long residual action of DDT stimulated the WHO program for global
eradication of malaria, and it still has major place in malaria control.
The compound known as DDT [50-29-3] ,
1,1¢-(2,2,2-trichloroethylidene)bis(4-chlorobenzene), is a white crystalline
solid, mp 109 °C, vapor pressure at 20 °C 0.025 mPa. Technical DDT is a
white amorphous powder containing 65 - 80 % of the active 4,4¢-DDT; 14 - 21
% of the nearly inactive 2,4¢-DDT [789-02-6] , mp 73 - 74 °C; up to 4 % of
the insecticidal DDD [72-54-8] ,
1,1¢-(2,2-dichloroethylidene)bis(4-chlorobenzene), mp 110 °C; and traces of
2,2¢-DDT and bis(4-chlorophenyl)sulfone. Technical DDT, mp 80 -94 °C, is
almost insoluble in water (1.2 mg/L, readily soluble in xylene and tetralin
(600 g/L), and moderately soluble in mineral oil and kerosene (50 - 80 g/L).
In alkaline solution, DDT is dehydrochlorinated readily to the
noninsecticidal 1,1-dichloroethenylidenebis(4-chlorobenzene) [72-55-9]
(DDE), mp 85 °C. This reaction also occurs in biological systems and
accounts for the storage and accumulation of DDE in lipid tissue of humans
and higher animals. The rat LD50 values of DDT are 113, 118 mg/kg (oral) and
2510 mg/kg (dermal).
Hydroxyalkylations (Table (8)) are extremely versatile; numerous alkyl- and
aryl-substituted aldehydes and ketones react with a variety of aromatic
compounds [144]. For instance, 1,1,1-trichloro-2-bis-(4-chlorophenyl)ethane
(DDT) [50-29-3], once a widely used insecticide, is formed from chloral and
chlorobenzene.
Trichloroacetaldehyde [75-87-6], chloral, 2,2,2-trichloroethanal, CCl3CHO,
Mr 147.39, was first synthesized by J. VON LIEBIG in 1832 by chlorination of
ethanol. It was the first hypnotic drug (1869) and is a precursor of the
famous insecticide DDT, 1,1,1-trichloro-2,2-bis(4-chlorophenyl)ethane
[50-29-3] , discovered in 1941. Chloral was an important chemical in the
1960s, but its importance has steadily declined since then because the use
of DDT and other chlorinated insecticides has been restricted.

Grazie mille!!!!! č una vera miniera di informazioni, peccato siano in
inglese. cmq grazie mille ancora!!!!!
andrea