CN101138730A

CN101138730A - Catalyzer for oxalic ester hydrogenation synthesizing of glycolate and method of preparing the same

Info

Publication number: CN101138730A
Application number: CNA2007100613918A
Authority: CN
Inventors: 王保伟; 张旭; 马新宾; 许根慧
Original assignee: Tianjin University
Current assignee: Tianjin University
Priority date: 2007-10-10
Filing date: 2007-10-10
Publication date: 2008-03-12
Anticipated expiration: 2027-10-10
Also published as: CN101138730B

Abstract

A catalyst for hydrogenated synthesis of glycollate with oxalate and a preparation method for the catalyst belong to the glycollate preparation technical field. The catalyst of the present invention uses the copper metal as the main active component, and silver as the promoter, and is manufactured with the method of immersion. A carrier of the catalyst is the modified silica sol. The select content of the copper metal is 5 to 45 percent of the carrier weight, and the optimal content of the copper metal is 10 to 40 percent. The content of silver metal is 0.1 to 15 percent of the carrier weight, and the optimal content of silver metal is 1 to 8.0 percent. The select carrier is the silica sol with a double peak pore distribution structure and the specific surface area of the carrier is 100-300m<SUP>2</SUP>/g; and the optimal specific surface area of the carrier is 120-240m<SUP>2</SUP>/g. The present invention settles the problem of applying a Cr/Cu catalyst in the oxalate gas-phase catalytic hydrogenation. Proven by experiments, the catalyst is provided with the very high reaction activity and glycollate selectivity in the reaction to synthesize glycollate with oxalate and hydrogen Moreover, the catalyst is provided with the long usable life and the stable reaction performance, and can be easily controlled.

Description

The Catalysts and its preparation method of oxalic ester hydrogenation synthesizing of glycolate

Technical field

The invention belongs to the preparing technical field of ethyl glycolate, further relate to a kind of Catalysts and its preparation method that is used for oxalic ester hydrogenation synthesizing of glycolate.

Background technology

Ethyl glycolate is with its distinctive molecular structure: have α-H, hydroxyl and ester group functional group simultaneously, make it have the chemical property of pure and mild ester concurrently, oxonation, hydrolysis, oxidation reaction etc. can take place, become a kind of important chemical material.Ethyl glycolate is the fine solvent of many celluloses, resin, rubber.Its downstream product glycolic, glycine, dimethyl malenate and glyoxalic acid etc. also are with a wide range of applications.

At present, the domestic production technology that does not have ripe eco-friendly ethyl glycolate.Still adopt chloroactic acid method production, its technology is that monoxone is mixed, stirs evenly with soda lye.On boiling water bath, heat, reduction vaporization, filtering sodium chloride, in oil bath, heat paste liquid, add the methyl alcohol and the concentrated sulfuric acid afterwards, reflux methyl glycollate, with sodium carbonate neutralization, placement is spent the night, vacuum fractionation gets the product ethyl glycolate.Its production process is long, energy consumption is high, seriously polluted, cost is high, suddenly waits to seek new process route.Opened up the new important channel that C-1 chemistry is produced oxalate by CO and nitrites synthesis of oxalic ester by gaseous catalysis.And then under catalytic action, the oxalate hydrogenation is come the ethanol production acid esters.Reported the new development of ethyl glycolate both at home and abroad successively.As in Deutsche Bundespatent 45603, use the Cr/Cu catalyst that makes by cupric and trivalent chromium that hydrogenation of oxalate for preparing is got ethyl glycolate.The Cr/Cu catalyst is the catalyst with ester class hydrogenation that is widely known by the people.But the inconvenience in industry is used has seriously reduced its practical value.Chromium is one of basis of this catalyst, but it efficiently and fully will be extracted very difficulty from used catalyst.Even the chromium of trace also has very big toxic action to human body, and this used catalyst is abandoned and will cause the serious environmental pollution.In addition, multiple non-Cr/Cu catalyst also obtains.As, Raney's nickel, nickel, cobalt, copper, iron, platinum, palladium, and oxide and sulfide etc.Yet these hydrogenation catalysts are not in all catalytic hydrogenation processes good effect to be arranged all.And will select especially according to multiple factor, as the model equation, reaction condition etc. of reaction.Otherwise reaction is efficiently carried out, and these selection of catalysts are not also set up guideline.Italy adopts H ₄Ru (CO) ₈(PBu ₃) ₂, Ru (CO) ₂(CH ₃COO) ₂(PBu ₃) ₂, [(Ph ₃P) (Ph ₂P) RuH ₂] ₂K ₂, carry out dimethyl oxalate hydrogenating reduction system methyl glycollate.180 ℃ of reaction temperatures, hydrogen 13.2MPa.These catalysis are the organic precious metal catalyst, complicated process of preparation, cost an arm and a leg and are difficult to and reclaim.By obtaining ethyl glycolate, also there are ethylene glycol and ethanol to generate simultaneously to the oxalate hydrogenation.When above-mentioned two kinds of materials occur, can separate and obtain ethyl glycolate product.So just introduced new process, and very unreasonable like this.As the process in the BP 2031883.Select ruthenium, nickel, Raney's nickel catalyst hydrogenation oxalate for use.Produce ethylene glycol or ethyl glycolate by the change condition.So not only improve the selectivity of ethyl glycolate but also avoided separating step.Use the Cr/Cu catalyst can bring environmental problem in the oxalate gas-phase catalytic hydrogenation.

Summary of the invention

The technical issues that need to address of the present invention are catalyst that are used for oxalic ester hydrogenation synthesizing of glycolate of a kind of eco-friendly high activity of development and high selectivity.

Catalyst of the present invention is main active component with metallic copper, is co-catalyst with silver, forms by immersion process for preparing.Its carrier is the Ludox of modification.Wherein metallic copper content is preferably 5%～45% of vehicle weight, and the best is 10%～40%; Argent content is 0.1%～15% of vehicle weight, and the best is 1%-8.0%.Carrier preferably has the Ludox of bimodal pore distribution structure, and its specific area is 100～300m ²/ g, the best is 120～240m ²/ g.

The method for preparing catalyst of the present invention comprises the steps:

(1) with Ludox through containing WITH AMMONIA TREATMENT 0.5～3 hour, then through 1100 ℃ of roastings 2～5 hours, the Ludox carrier of preparation remodeling.

(2) halide, acetate, sulfate or the nitrate dissolving with metallic copper is mixed with the aqueous solution, the concentration of solution is 0.002～1.50M, to flood in this solution 10～24 hours through the modified silicasol carrier that step (1) makes, then, vacuum drying got solids in 4～8 hours;

(3) nitrate, acetate or oxalates and the water with argent is mixed with the aqueous solution, the concentration of the aqueous solution is 0.001～0.10M, the solids that step (2) is made soaks in this aqueous solution after 3～10 hours and takes out, 90～120 ℃ of dryings 6～8 hours, again 200～400 ℃ of roastings after 2～6 hours solids;

(4) be 20～60ml/min.g.cat with flow, hydrogeneous be the mist of 20% nitrogen and hydrogen or contain CO be the mist of 25% CO and nitrogen 200～650 ℃ of reductase 12～10 hour, just can be made into catalyst of the present invention.

The invention solves the problem of in the oxalate gas-phase catalytic hydrogenation, using the Cr/Cu catalyst, experiment shows that this catalyst all has the very high reactivity and the selectivity of ethyl glycolate in oxalate and the reaction of hydrogen synthesizing alcohol acid esters, and the life-span is long, reactivity worth is steady, is easy to control.

The specific embodiment

Ludox through containing WITH AMMONIA TREATMENT 0.5～3 hour, then through 1100 ℃ of roastings 2～5 hours, is prepared the Ludox carrier of remodeling.Halide, acetate, sulfate or the nitrate dissolving of metallic copper are mixed with the aqueous solution, the concentration of solution is 0.002～1.50M, the modified silicasol carrier that makes was flooded in this solution 10～24 hours, and then, vacuum drying got solids in 4～8 hours.Nitrate, acetate or oxalates and the water of argent are mixed with the aqueous solution, the concentration of the aqueous solution is 0.001～0.10M, the above-mentioned solids that makes soaked in this aqueous solution after 3～10 hours take out, 90～120 ℃ of dryings 6～8 hours, again 200～400 ℃ of roastings after 2～6 hours solids; With flow is 20～60ml/min.g.cat, hydrogeneous be the mist of 20% nitrogen and hydrogen or contain CO be the mist of 25% CO and nitrogen 200～650 ℃ of reductase 12～10 hour, just can be made into catalyst of the present invention.

The invention will be further described by the following examples:

Embodiment 1:

Take by weighing two parts in Ludox 100g carrier, a processing through modification (is designated as SiO ₂(M)), a non-modified is handled and (is designated as SiO ₂(W).Press 15wt%Cu+5wt%Ag/SiO ₂Content preparation catalyst, its step is as follows: choose copper nitrate, be mixed with maceration extract according to the Cu load capacity, load capacity is mixed with maceration extract, with the modification SiO that makes ₂Carrier flooded in this solution after 24 hours, and vacuum drying got solids in 8 hours.Choose Ag (NO ₃) ₃Be mixed with maceration extract according to the Ag load capacity, for preventing that Hydrolysis Reactions of Metal-ions from generating hydroxide or oxide precipitation, in maceration extract, add a small amount of nitric acid, make PH=5～6 of maceration extract, above-mentioned then solids soaked in maceration extract 10 hours, after fully absorbing, in water-bath, be dried to solid, again that solid is following dry 8 hours at 120 ℃, 650 ℃ of roastings 6 hours, then with flow be 400ml/min hydrogeneous be 20% the nitrogen and the mist of hydrogen, 450 ℃ of reduction 6 hours, just make Cu-Ag/SiO ₂Catalyst.Be designated as respectively: Cu-Ag/SiO ₂(M) and Cu-Ag/SiO ₂(W).

Embodiment 2:

Take by weighing two parts in the Ludox carrier of 100g modification, press 20wt%Cu+6wt%Ag/SiO ₂Content preparation catalyst, its step is as follows: choose copper chloride, be mixed with maceration extract according to the Cu load capacity, load capacity is mixed with maceration extract, the modified silicasol carrier that makes flood 10 hours in this solution after, vacuum drying 6 hours must solids.Choose Ag (NO ₃) ₃Be mixed with maceration extract according to the Ag load capacity, for preventing that Hydrolysis Reactions of Metal-ions from generating hydroxide or oxide precipitation, in maceration extract, add a small amount of nitric acid, make the PH=6.5 of maceration extract, Ludox carrier with modification soaked in maceration extract 10 hours then, after fully absorbing, in water-bath, be dried to solid, again that solid is following dry 6 hours at 120 ℃, 500 ℃ of roastings 6 hours, respectively with flow be 200ml/min hydrogeneous be the mist of 20% nitrogen and hydrogen and contain CO be the mist of 25% CO and nitrogen at 600 ℃ of reductase 12s hour, just make Cu-Ag/SiO ₂Catalyst.Be designated as respectively: Cu-Ag/SiO ₂(H) and Cu-Ag/SiO ₂(C).

The catalyst performance test:

Catalyst places the reactor of quartz glass, dress thermocouple sheath in the reactor inside diameter 20mm, reactor, and loaded catalyst is 10ml, by beds, by reactor bottom drawn from top to bottom by the product ethyl glycolate for unstripped gas.The optimum flow ratio of reaction gas hydrogen and oxalate mol ratio is 80, is reflected under the 1.5MPa to carry out, and reaction temperature is 180 ℃.Reaction result is as shown in table 1.

Table 1 catalyst performance test result

Catalyst	Dimethyl oxalate conversion ratio/%	Diethy-aceto oxalate conversion ratio/%	Methyl glycollate selectivity %	Ethyl glycolate selectivity %
Catalyst	Dimethyl oxalate conversion ratio/%	Diethy-aceto oxalate conversion ratio/%	Methyl glycollate selectivity %	Ethyl glycolate selectivity %	Cu-Ag/SiO ₂(W)	＞75	＞80	62	61
Cu-Ag/SiO ₂(M)	＞85	＞95	83	81	Cu-Ag/SiO ₂(W)	＞75	＞80	62	61
Cu-Ag/SiO ₂(M)	＞85	＞95	83	81	Cu-Ag/SiO ₂(H)	＞85	＞95	83	84
Cu-Ag/SiO ₂(C)	＞85	＞95	82	83	Cu-Ag/SiO ₂(H)	＞85	＞95	83	84

Claims

1. the catalyst of an oxalic ester hydrogenation synthesizing of glycolate is characterized in that, described catalyst is main active component with metallic copper, is co-catalyst with silver, and its carrier is the Ludox of modification; Wherein metallic copper content is 5%～45% of vehicle weight; Argent content is 0.1%～15% of vehicle weight.

2. according to the catalyst of the described a kind of oxalic ester hydrogenation synthesizing of glycolate of claim 1, it is characterized in that metallic copper content is 10%～40% of vehicle weight.

3. according to the catalyst of the described a kind of oxalic ester hydrogenation synthesizing of glycolate of claim 1, it is characterized in that argent content is 1%～8% of vehicle weight.

4. according to the catalyst of the described a kind of oxalic ester hydrogenation synthesizing of glycolate of claim 1, it is characterized in that carrier is selected the Ludox of bimodal pore distribution structure for use, its specific area is 100～300m ²/ g.

5. according to the catalyst of the described a kind of oxalic ester hydrogenation synthesizing of glycolate of claim 1, it is characterized in that, the Ludox of selected bimodal pore distribution structure, specific area is 120～240m ²/ g.

6. the Preparation of catalysts method of an oxalic ester hydrogenation synthesizing of glycolate comprises the steps:

(1) with Ludox through containing WITH AMMONIA TREATMENT 0.5～3 hour, then through 1100 ℃ of roastings 2～5 hours, the Ludox carrier of preparation remodeling;