CN1040744C

CN1040744C - Extraction of natural guaiacol

Info

Publication number: CN1040744C
Application number: CN93102022A
Authority: CN
Inventors: 罗富源; 吴联真
Original assignee: Individual
Current assignee: Individual
Priority date: 1993-02-18
Filing date: 1993-02-18
Publication date: 1998-11-18
Anticipated expiration: 2013-02-18
Also published as: CN1114956A

Abstract

The present invention relates to the extraction of natural guaiacol from forest chemical creosote. The present guaiacol produced by adopting a synthetic process in China has the defects of low purity and high cost, and one of auxiliary materials is imported. The extraction of natural guaiacol of the present invention comprises: natural guaiacol in forest chemical creosote produces insoluble salt; then, after the procedures of filtration, acidization, rectification, etc. of the insoluble salt, natural guaiacol with purity higher than 95% can be obtained, and extraction rate reaches more than 60%. The quality of vanillin produced by using the natural guaiacol is much better than that of vanillin produced by using synthetic guaiacol. All the raw auxiliary materials adopted by the present invention are from China, and thus, the production cost of the present invention is 30% lower than that of the synthetic process.

Description

Extraction of natural guaiacol

The guaiacol is prepared by adopting a synthesis process at present in China, the purity of the obtained guaiacol is low, the cost is high, one raw material, namely the o-nitrochlorobenzene is imported, and the o-nitrochlorobenzene is converted into o-aminoanisole by a special factory after being imported to be used.

The natural guaiacol is widely present in hardwood dry distillation oil, the content of the pine root dry distillation impure phenol is up to 26 percent, the natural guaiacol is not developed and utilized all the time, and most of the natural guaiacol is burnt out along with light oil as fuel; some dry distillation turpentine oil manufacturers directly discharge the fusel oil into rivers due to no market for the miscellaneous phenols, thereby polluting the environment. The invention aims to extract natural guaiacol by completely adopting domestic raw and auxiliary materials, improve the purity and find an extraction method.

After several years of repeated exploration, four methods for extracting natural guaiacol have been developed, these four methods being:

the first is a calcium salt method, and the reaction formula is as follows:

filtering, washing, acid separating, washing and rectifying the calcium guaiacol precipitate to obtain the natural guaiacol product.

The second method is a magnesium salt method, and the reaction formula is as follows:

filtering, washing, acid separating, washing again and rectifying the guaiacol magnesium salt precipitate to obtain the natural guaiacol.

The two methods for extracting natural guaiacol are characterized by that it utilizes the property of that the alkoxyphenol of guaiacol, etc. and alkaline earth metal can be used to produce insoluble salt, and can be separated from other phenols.

The third is the sodium salt method, which has the reaction formula:

the natural guaiacol sodium salt is obtained by filtering, washing, acid precipitation, re-washing and rectification.

The fourth is the potassium salt process, which has the formula:

the natural guaiacol potassium salt is obtained by filtering, washing, acid precipitation, re-washing and rectification.

The third and fourth methods are to separate the alkoxyphenol such as natural guaiacol from other monophenol by utilizing the characteristic that the alkoxyphenol can generate crystalline solid with sodium hydroxide and potassium hydroxide solution.

Figure 1 is a block diagram of a process for extracting natural guaiacol. Now, the calcium salt method is taken as an example to explain the extraction of the natural guaiacol in detail. The first step is extraction, extracting the forest impure phenol containing guaiacol into a stainless steel reaction kettle, then adding 10% sodium hydroxide, fully and uniformly stirring the forest impure phenol and the guaiacol, and then adding 20% calcium acetate solution while stirring. The dosage of the three raw materials is 2 parts, 6 parts and 3 parts by weight respectively according to the sequence of adding materials. The second step is filtration, and after the extract is cooled and crystallized, the upper mother liquor is extracted. And the third step is to discharge clean water to wash the sediment twice and pump out the washing water. And fourthly, acid precipitation, namely adding sulfuric acid with the concentration adjusted to 30% from the elevated tank, fully stirring, gradually floating the crude guaiacol on the upper layer, discharging sulfate wastewater from the bottom after the acid precipitation is finished, and then washing the crude guaiacol twice by using clean water.

The four steps are all carried out in the same stainless steel reaction kettle. And if the three raw and auxiliary materials and the parts by weight in the first step are taken as the reference, the amount of the 30% sulfuric acid in the fourth step is 2.84 parts. And fifthly, carrying out reduced pressure rectification, pumping the washed crude guaiacol into a stainless steel rectification kettle, controlling the vacuum degree in the kettle to be 0.082-0.083 MPa, controlling the temperature in the kettle through heating equipment, and collecting a fraction within the range of 148-151 ℃, wherein the fraction is the natural guaiacol. If the vacuum in the kettle is different, the temperature of the collected fraction is changed correspondingly.

The raw and auxiliary materials of the guaiacol synthesized in China at present are sodium nitrite, anthranilate and sulfuric acid, and the anthranilate is obtained by converting imported o-nitrochlorobenzene by a special factory. By adopting the method for extracting the natural guaiacol, all raw and auxiliary materials are taken at home, foreign exchange is saved, and the purity of the obtained natural guaiacol is two percent higher than that of the domestic synthetic guaiacol and can reach 97 percent. The prior impure phenol discharged into rivers finds a new way, not only reduces the environmental pollution, but also increases the economic income, the extraction rate of the natural guaiacol reaches more than 60 percent, and the production cost is about 30 percent lower than that of the synthetic method. Vanillin produced with natural guaiacol is of much better quality than vanillin produced with synthetic guaiacol.

The best embodiment of the invention is as follows: 100 kg of lignified heterophenol containing 26% of guaiacol, 300 kg of sodium hydroxide solution containing 10%, 150 kg of calcium acetate solution containing 20% and 122 kg of sulfuric acid containing 30%, namely the required four raw and auxiliary materials are 2 parts, 6 parts, 3 parts and 2.84 parts by weight respectively, and the steps and the technical conditions are carried out according to the method in the specification to obtain 18 kg of natural guaiacol with the content of 95%, wherein the extraction rate is 69.23%.

Claims

1. The method for extracting the natural guaiacol from the forest chemical impure phenol is characterized by comprising the following steps: the first step is extraction, the forest chemical impure phenol containing guaiacol is pumped into a stainless steel reaction kettle, and then sodium hydroxide with the concentration of 10 percent is added to fully and evenly stir the two; the second step is filtration, and after the extract is cooled and crystallized, the upper mother liquor is extracted; thirdly, discharging clean water for washing, and pumping out washing water; fourthly, acid precipitation, namely adding sulfuric acid with the concentration adjusted to 30 percent, fully stirring, discharging sulfate wastewater from the bottom after the acid precipitation is finished, and then washing crude guaiacol by using clear water; the four steps are carried out in the same stainless steel reaction kettle; and fifthly, carrying out reduced pressure rectification, pumping the washed crude guaiacol into a stainless steel rectifying still, and heating the rectifying still through heating equipment, wherein the vacuum degree in the rectifying still corresponds to the temperature of the collected natural guaiacol one byone.

2. The method of claim 1 for extracting natural guaiacol from linza phenols, comprising the steps of: in the first step, 10% of sodium hydroxide is added, and 10% of potassium hydroxide is added instead.

3. The method of claim 1 for extracting natural guaiacol from linza phenols, comprising the steps of: in the first step, after the two materials are fully and uniformly mixed, the calcium acetate solution with the concentration of 20 percent is added while stirring, and the three raw materials and the auxiliary materials are respectively 2 parts, 6 parts and 3 parts by weight according to the adding sequence of the materials.

4. The method of claim 1 for extracting natural guaiacol from linza phenols, comprising the steps of: in the first step, the magnesium acetate solution is added while stirring after the two are fully stirred.