US 2026/0132096 A1 · IMPROVED PROCESS FOR PRODUCTION OF ALKALI METAL METHOXIDES

Abstract

The present invention relates to a process for producing at least one alkali metal methoxide by reactive distillation in at least one reaction column. At the lower end of the reaction column(s), the respective alkali metal methoxide dissolved in methanol is withdrawn. The methanol/water mixture obtained at the top of the reaction column(s) is separated by distillation in a rectification column. The energy from the vapour obtained at the top of the rectification column is transferred to a liquid or gaseous heat transfer medium, and the gaseous heat transfer medium obtained as a result is compressed in at least two stages. The energy from the respectively compressed heat transfer medium is advantageously transferred to the bottom stream and sidestream from the rectification column. This enables particularly energy-efficient use of the energy from the vapour in the process of the invention. The energy from the compressed heat transfer medium may additionally be used for operation of the reaction column(s) or for operation of a reaction column in which a process for transalcoholization of alkali metal alkoxides is conducted.

Claims21

Dependent claims

1-15. (canceled)

A process for preparing at least one alkali metal methoxide of the formula MAOCH3 wherein MA is sodium, lithium, or potassium, said process comprising:

(a1) a reactant stream SAE1 comprising methanol is reacted with a reactant stream SAE2 comprising MAOH in countercurrent in a reactive rectification column RRA to produce a crude product RPA comprising MAOCH3, water, methanol, MAOH;
wherein a bottom product stream SAP comprising methanol and MAOCH3 is withdrawn at the lower end of RRA and a vapour stream SAB comprising water and methanol is withdrawn at the upper end of RRA;
(a2) simultaneously with, and spatially separate from, step (a1), a reactant stream SBE1 comprising methanol is reacted with a reactant stream SBE2 comprising MBOH in countercurrent in a reactive rectification column RRB to give a crude product RPB comprising MBOCH3, water, methanol, and MBOH, wherein MB is selected from sodium, lithium, potassium;
wherein a bottom product stream SBP comprising methanol and MBOCH3 is withdrawn at the lower end of RRB and a vapour stream SBB comprising water and methanol is withdrawn at the upper end of RRB;
(a3) at least a portion of vapour stream SAB, and at least a portion of vapour stream SBB, mixed with SAB or separate from SAB, is directed into a rectification column RDA and separated in RDA into at least one vapour stream SOA comprising methanol, which is withdrawn at the upper end of RDA, and at least one stream SUA comprising water, which is withdrawn at the lower end of RDA;
(b) at least one side stream SZA is withdrawn from RDA and recycled back into RDA;
(c) energy is transferred from at least a portion of SOA to a liquid or gaseous heat transfer medium W*1, to produce gaseous heat transfer medium W*2;
(d) at least a portion of the gaseous heat transfer medium W*2 is compressed to obtain a gaseous heat transfer medium W*3 that has been compressed relative to W*2;
(e) energy is transferred from a first portion W*31 of the gaseous heat transfer medium W*3 to SZA before SZA is recycled into RDA;
(f) a portion of the gaseous heat transfer medium W*3 other than W*31, W*32, is compressed further to obtain a gaseous heat transfer medium W*4 that has been compressed relative to W*31;
and
(g) energy is transferred from at least a portion of W*4 to at least a portion SUA1 of SUA before SUA1 is recycled into RDA.

9 more elements

A process for preparing at least one alkali metal methoxide of the formula MAOCH3 wherein MA is selected sodium, lithium, or potassium, and wherein:

(a1) a reactant stream SAE1 comprising methanol is reacted with a reactant stream SAE2 comprising MAOH in countercurrent in a reactive rectification column RRA to produce a crude product RPA comprising MAOCH3, water, methanol, and MAOH;
wherein a bottom product stream SAP comprising methanol and MAOCH3 is withdrawn at the lower end of RRA and a vapour stream SAB comprising water and methanol is withdrawn at the upper end of RRA;
(a3) at least a portion of the vapour stream SAB, and at least a portion of the vapour stream SBB, mixed with SAB or separate from SAB, is directed into a rectification column RDA and separated in RDA into at least one vapour stream SOA comprising methanol, which is withdrawn at the upper end of RDA, and at least one stream SUA comprising water, which is withdrawn at the lower end of RDA;
(b) at least one side stream SZA is withdrawn from RDA and recycled back into RDA;
(c) energy is transferred from at least a portion of SOA to a liquid or gaseous heat transfer medium W*1, to produce a gaseous heat transfer medium W*2;
(d) at least a portion of the gaseous heat transfer medium W*2 is compressed to obtain a gaseous heat transfer medium W*3 that has been compressed relative to W*2;
(e) energy is transferred from a first portion W*31 of the gaseous heat transfer medium W*3 to SZA before SZA is recycled into RDA;
(f) a portion of the gaseous heat transfer medium W*3 other than W*31, W*32, is compressed further to obtain a gaseous heat transfer medium W*4 that has been compressed relative to W*31;
and
(g) energy is transferred from at least a portion of W*4 to at least a portion SUA1 of SUA before SUA1 is recycled into RDA.

7 more elements

Dependencies are inferred from the claim text.

Facts

Application

19/121,093Filed 20 Oct 2022

Published

14 May 2026

Term ends

Not estimatedThe source records don’t support an estimate.

Classification12 codes

C07C 29/70
Preparation of metal alcoholates: by converting hydroxy groups to O-metal groups
B01D 1/2856
Special features relating to the compressed vapour: the compressed vapour is used for heating a reboiler or a heat exchanger outside an evaporator
B01D 3/007
Distillation or related exchange processes in which liquids are contacted with gaseous media, e.g. stripping: energy recuperation; Heat pumps
B01D 3/009
Distillation or related exchange processes in which liquids are contacted with gaseous media, e.g. stripping: in combination with chemical reactions

Improved process for production of alkali metal methoxides

Life of this patent

Improved process for production of alkali metal methoxides

Life of this patent

Abstract

Claims21