阅读说明：本技术 一种对称草酸酯的生产工艺 (A kind of production technology of symmetrical oxalate ) 是由 孙会显 于 2019-09-24 设计创作，主要内容包括：一种对称草酸酯的生产工艺,包括以下步骤：预热升温、催化反应以及脂交换反应,反应塔塔釜得到草酸二甲酯、目标产物草酸酯、草酸非对称酯的混合物,另有过量的醇,塔釜产物泵连续出料至醇回收塔,塔顶回收过量的醇,塔釜物料连续进入低沸物塔,低沸物塔塔中进料,塔顶才出低沸物,塔釜物料连续进入成品塔,成品塔塔顶采出得到产品；本发明的工艺是采用草酸二甲酯与醇发生脂交换反应,生成对应的对称草酸酯,通过精制得到产品,反应时间短且收率高,制得推广。(A kind of production technology of symmetrical oxalate, the following steps are included: pre-heating temperature elevation, catalysis reaction and transesterification reaction, reaction tower tower reactor obtains the mixture of dimethyl oxalate, target product oxalate, the asymmetric ester of oxalic acid, separately there is excessive alcohol, and tower kettle product pumps continuous discharge to alcohol recovery tower, the excessive alcohol of recovered overhead, kettle material continuously enters low-boiling-point substance tower, feeds in low-boiling-point substance tower tower, and tower top just goes out low-boiling-point substance, kettle material continuously enters finishing column, and finishing column overhead extraction obtains product；Technique of the invention is that transesterification reaction occurs using dimethyl oxalate and alcohol, generates corresponding symmetrical oxalate, and by being refining to obtain product, the reaction time is short and high income, is made and promotes.)

1. a kind of production technology of symmetrical oxalate, which comprises the following steps:

S1: prepare to mix in dimethyl oxalate and alcohol investment mixer, heat up into preheater；

S2: the logistics after preheating enters the upper middle part of reaction tower, reacts under the action of catalyst in tower；

S3: reaction tower tower reactor obtains the mixture of dimethyl oxalate, target product oxalate, the asymmetric ester of oxalic acid, separately there is excess Alcohol, tower kettle product pumps continuous discharge to alcohol recovery tower, and the excessive alcohol of recovered overhead, kettle material continuously enters low-boiling-point substance tower, It is fed in low-boiling-point substance tower tower, tower top just goes out low-boiling-point substance, and kettle material continuously enters finishing column, and finishing column overhead extraction is produced Product.

2. a kind of production technology of symmetrical oxalate according to claim 1, it is characterised in that: mole of alcohol in the S1 Than for 2-20:1.

3. a kind of production technology of symmetrical oxalate according to claim 1, it is characterised in that: participate in reaction in the S2 Alcohol moisture content be 0.2-5%.

4. a kind of production technology of symmetrical oxalate according to claim 1, it is characterised in that: urged in the tower in the S2 Agent uses solid acid or solid base catalyst.

5. according to claim 1 with a kind of production technology of symmetrical oxalate described in 4, it is characterised in that: the fixed acid is urged Agent is one of resin cation, acidic molecular sieve, solid super-strong acid, acidic ion liquid, load type active carbon and silica gel Or it is a variety of；The solid base catalyst be conventional alkali, anion exchange resin and activated carbon supported alkali compounds one kind or It is a variety of.

6. a kind of production technology of symmetrical oxalate according to claim 1, it is characterised in that: alcohol recovery tower in the S3 Using pressurization or atmospheric operation, pressure 0.1-0.4MPa is controlled, de- low-boiling-point substance tower and finishing column are all made of vacuumizing, and control is true Reciprocal of duty cycle 0.095-0.099 MPa.

7. a kind of production technology of symmetrical oxalate according to claim 1, it is characterised in that: the finishing column in the S3 Kettle material is that the continuous reaction tower that returns is fed.

Technical field

The present invention relates to pharmaceuticals industry technical field, specially a kind of production technology of symmetrical oxalate.

Background technique

Diethy-aceto oxalate is the required chemicals of pharmaceuticals industry, majority be produced as oxalic acid and corresponding alcohol in catalyst and It is produced under the action of water entrainer, yield is low and the reaction time is long；For this purpose, it is proposed that a kind of production technology of symmetrical oxalate.

Summary of the invention

The purpose of the present invention is to provide a kind of production technologies of symmetrical oxalate, are asked with solve to propose in background technique Topic.

To achieve the above object, the invention provides the following technical scheme: a kind of production technology of symmetrical oxalate, including with Lower step:

S1: prepare to mix in dimethyl oxalate and alcohol investment mixer, heat up into preheater；

S2: the logistics after preheating enters the upper middle part of reaction tower, reacts under the action of catalyst in tower；

S3: reaction tower tower reactor obtains the mixture of dimethyl oxalate, target product oxalate, the asymmetric ester of oxalic acid, separately there is excess Alcohol, tower kettle product pumps continuous discharge to alcohol recovery tower, and the excessive alcohol of recovered overhead, kettle material continuously enters low-boiling-point substance tower, It is fed in low-boiling-point substance tower tower, tower top just goes out low-boiling-point substance, and kettle material continuously enters finishing column, and finishing column overhead extraction is produced Product.

Preferably, the molar ratio of alcohol is 2-20:1 in the S1.

Preferably, the alcohol moisture content that reaction is participated in the S2 is 0.2-5%.

Preferably, catalyst uses solid acid or solid base catalyst in the tower in the S2.

Preferably, the fixed acid catalyst is resin cation, acidic molecular sieve, solid super-strong acid, acidic ionic liquid One of body, load type active carbon and silica gel are a variety of；The solid base catalyst is conventional alkali, anion exchange resin and work Property charcoal load alkali compounds it is one or more.

Preferably, alcohol recovery tower controls pressure 0.1-0.4MPa using pressurization or atmospheric operation in the S3, takes off low-boiling-point substance Tower and finishing column are all made of vacuumizing, control vacuum degree 0.095-0.099 MPa.

Preferably, the finished product tower reactor material in the S3 is that the continuous reaction tower that returns is fed.

Compared with prior art, the beneficial effects of the present invention are: technique of the invention is sent out using dimethyl oxalate and alcohol Raw transesterification reaction generates corresponding symmetrical oxalate, and by being refining to obtain product, the reaction time is short and high income, is made and pushes away Extensively.

Specific embodiment

Below in conjunction with the embodiment of the present invention, technical scheme in the embodiment of the invention is clearly and completely described, Obviously, described embodiments are only a part of the embodiments of the present invention, instead of all the embodiments.Based in the present invention Embodiment, every other embodiment obtained by those of ordinary skill in the art without making creative efforts, all Belong to the scope of protection of the invention.