Alkaline hydrolysis of dimethyl terephthalate in the presence of [LiAl{sub 2}(OH){sub 6}]Cl.2H{sub 2}O

Journal Article · Tue Nov 14 23:00:00 EST 2006 · Journal of Solid State Chemistry

OSTI ID:20900897

Lixu, Lei ^[1]; Weifeng, Zhang ^[1]; Meng, Hu ^[1]; Hegen, Zheng ^[2]

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1. Department of Chemistry and Chemical Engineering, Southeast University, Nanjing 210096 (China)
2. State Key Laboratory of Coordination Chemistry, Nanjing 210093 (China)

The alkaline hydrolysis of dimethyl terephthalate (DMT) in the presence of [LiAl{sub 2}(OH){sub 6}]Cl has been investigated to demonstrate a possible application of anion exchange facility of layered double hydroxides (LDHs) to control chemical reactions. The results show that (i) in the alkaline hydrolysis of DMT in the presence of [LiAl{sub 2}(OH){sub 6}]Cl, most of the interlayer Cl{sup -} of [LiAl{sub 2}(OH){sub 6}]Cl is quickly replaced by OH{sup -} in the alkaline solution because the LDH host favors OH{sup -} more; (ii) the alkaline hydrolysis of DMT in the presence of [LiAl{sub 2}(OH){sub 6}]Cl is faster than the reaction of DMT and [LiAl{sub 2}(OH){sub 6}]OH; (iii) The hydrolysis of DMT in a buffer solution of pH{approx}8 takes longer time to reach equilibrium than the alkaline hydrolysis of DMT in the presence of [LiAl{sub 2}(OH){sub 6}]Cl. It is believed that the selective anion exchange chemistry of the LDH plays a key role in storage and controlled release of active reactant, that is, OH{sup -}, thus make the hydrolysis proceeds in a controlled way. - Graphical abstract: XRD patterns of the solid products of the alkaline hydrolysis of dimethyl terephthalate (DMT) in the presence of [LiAl{sub 2}(OH){sub 6}]Cl at 70 deg. C halted at different time, which shows that [LiAl{sub 2}(OH){sub 6}]Cl turns out to be [LiAl{sub 2}(OH){sub 6}]OH, and [LiAl{sub 2}(OH){sub 6}]{sub 2}TP forms gradually. In this reaction, the alkaline hydrolysis of DMT is controlled by replacement of Cl{sup -} in [LiAl{sub 2}(OH){sub 6}]Cl by OH{sup -}, and subsequent replacement of OH{sup -} in [LiAl{sub 2}(OH){sub 6}]OH by terephthalate anion.

• OSTI ID: 20900897
• Journal Information: Journal of Solid State Chemistry, Journal Name: Journal of Solid State Chemistry Journal Issue: 11 Vol. 179; ISSN 0022-4596; ISSN JSSCBI
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
ALKALINE HYDROLYSIS
ALUMINIUM HYDROXIDES
ANIONS
CHLORIDES
CHLORINE IONS
EQUILIBRIUM
ION EXCHANGE
LITHIUM HYDROXIDES
SOLUTIONS
TEREPHTHALIC ACID
X-RAY DIFFRACTION