阅读说明：本技术 一种用于制备液体石蜡的动植物油脂的预处理方法 (Animal and vegetable oil pretreatment method for preparing liquid paraffin ) 是由 赵紫华 尹娇 郭存敬 周凌 于 2019-08-26 设计创作，主要内容包括：本发明公开了一种用于制备液体石蜡的动植物油脂的预处理方法,其步骤为：1)将废弃动植物油脂蒸汽蒸馏,分离出脂肪酸,备用；2)向步骤1)蒸汽蒸馏剩余废油脂中加入酸的水溶液进行酸处理；3)加入水进行水化处理；4)静置,经油水分离,除去废水,剩余油相进行真空干燥；干燥至含水量≤0.5Wt.％,干燥后物料与步骤1)蒸馏所得脂肪酸混合,得到处理后动植物油脂。本发明方法可使动植物油脂中的金属离子及其他元素和杂质脱除,预处理后的动植物油脂,在制备液体石蜡的过程中,降低了对加氢催化剂中毒、板结和结焦等现象的出现,制备得到的液体石蜡收率高、品质好。(The invention discloses a pretreatment method of animal and vegetable oil for preparing liquid paraffin, which comprises the following steps: 1) distilling waste animal and vegetable oil with steam to separate out fatty acid for later use; 2) adding an acid aqueous solution into the residual waste oil and fat obtained by steam distillation in the step 1) for acid treatment; 3) adding water for hydration treatment; 4) standing, performing oil-water separation, removing wastewater, and vacuum drying the residual oil phase; drying until the water content is less than or equal to 0.5 Wt.%, and mixing the dried material with the fatty acid obtained by distillation in the step 1) to obtain the treated animal and vegetable oil. The method can remove metal ions, other elements and impurities in the animal and vegetable oil, reduces the phenomena of poisoning, hardening, coking and the like of the hydrogenation catalyst in the process of preparing the liquid paraffin after pretreatment, and ensures that the prepared liquid paraffin has high yield and good quality.)

1. A pretreatment method of animal and vegetable oil for preparing liquid paraffin comprises the following steps:

1) heating the waste animal and vegetable oil to 200-280 ℃, and carrying out steam distillation under the pressure of-80 to-101 kPa to separate free fatty acid in the waste animal and vegetable oil for later use;

2) adding an aqueous solution of 50-85 wt.% acid into the residual waste oil and fat obtained by steam distillation in the step 1) for acid treatment, controlling the temperature to be 60-80 ℃, and controlling the acid treatment time to be 30-60 min; the water solution of the acid accounts for 1-15% of the mass of the residual waste oil and fat in the steam distillation in the step 1);

3) adding water into the mixture obtained in the step 2), controlling the temperature to be 60-80 ℃, and carrying out hydration treatment for 30-60 min; the water accounts for 1-30% of the mass of the residual waste oil in the steam distillation in the step 1);

4) step 3), after hydration treatment is finished, controlling the temperature of the material to be 60-80 ℃, standing, keeping the temperature of the material to be 60-80 ℃, performing oil-water separation, separating liquid to remove waste water, and performing vacuum drying on the residual oil phase; drying at the temperature of 110-150 ℃ and under the pressure of-0.02 MPa to-0.10 MPa until the water content is less than or equal to 0.5 Wt.%, and mixing the dried material with the fatty acid obtained by distillation in the step 1) to obtain the treated animal and vegetable oil.

2. The pretreatment method of animal and vegetable fats and oils for preparing liquid paraffin according to claim 1, characterized in that: the waste animal and vegetable oil is selected from one or more of acidified oil, illegal cooking oil, catering oil, vegetable fat, animal oil and animal fat.

3. The pretreatment method of animal and vegetable fats and oils for preparing liquid paraffin according to claim 2, characterized in that: the acidified oil is soybean acidified oil or palmitic acid oil.

4. The pretreatment method of animal and vegetable fats and oils for preparing liquid paraffin according to claim 1, characterized in that: the acid used for the acid treatment in the step 2) is an organic acid or an inorganic acid.

5. The method for pretreating animal and vegetable fats and oils for preparing liquid paraffin according to claim 4, wherein: the organic acid or the inorganic acid is: phosphoric acid, citric acid, sulfuric acid, or oxalic acid.

6. The pretreatment method of animal and vegetable fats and oils for preparing liquid paraffin according to claim 1, characterized in that: the water in the step 3) is primary water, the light absorption rate is 254nm, and the optical path of 1 cm: less than or equal to 0.001 and the conductivity less than or equal to 0.01 mS/m.

Technical Field

The invention belongs to the field of animal and vegetable oil pretreatment for preparing liquid paraffin. In particular to a pretreatment method of animal and vegetable oil for preparing liquid paraffin. The method is widely used for preparing the liquid paraffin by using animal and vegetable oil such as palmitic acid oil, waste oil of kitchen and kitchen, illegal cooking oil, soybean oil, coconut oil and the like.

Background

The quantity of waste oil produced in China every year is very large, the waste oil and waste cooking oil recovered from large and medium cities are used for preparing the liquid paraffin, and the liquid paraffin is used as a raw material, so that the production cost of the liquid paraffin can be reduced, industrial waste oil and other waste oil can be comprehensively utilized, waste materials are changed into valuable materials, and the coordinated development of economy and environmental protection is realized.

With the decreasing of non-renewable energy and the growing concern of environmental pollution, the development of new and environmentally friendly chemical synthesis routes has become one of the hot topics of scientific research today. The method for converting the waste oil into the liquid paraffin has the advantages of adopting renewable biomass raw materials, realizing low-carbon emission and the like, and has important significance for reducing the gas concentration at the room temperature of the atmosphere, improving the living environment of human beings and realizing the sustainable development of economy. The method can treat the waste oil and fat, so that the treated oil can be used for preparing liquid paraffin.

Disclosure of Invention

The technical problem to be solved by the invention is as follows: provides a pretreatment method of animal and vegetable oil for preparing liquid paraffin.

In order to solve the technical problems, the technical scheme provided by the invention is as follows: a pretreatment method of animal and vegetable oil for preparing liquid paraffin comprises the following steps:

1) heating the waste animal and vegetable oil to 200-280 ℃, and carrying out steam distillation under the pressure of-80 to-101 kPa to separate free fatty acid in the waste animal and vegetable oil for later use;

2) adding an aqueous solution of 50-85 wt.% acid into the residual waste oil and fat obtained by steam distillation in the step 1) for acid treatment, controlling the temperature to be 60-80 ℃, and controlling the acid treatment time to be 30-60 min; the water solution of the acid accounts for 1-15% of the mass of the residual waste oil and fat in the steam distillation in the step 1);

3) adding water into the mixture obtained in the step 2), controlling the temperature to be 60-80 ℃, and carrying out hydration treatment for 30-60 min; the water accounts for 1-30% of the mass of the residual waste oil in the steam distillation in the step 1);

4) step 3), after hydration treatment is finished, controlling the temperature of the material to be 60-80 ℃, standing, keeping the temperature of the material to be 60-80 ℃, performing oil-water separation, separating liquid to remove waste water, and performing vacuum drying on the residual oil phase; drying at the temperature of 110-150 ℃ and under the pressure of-0.02 MPa to-0.10 MPa until the water content is less than or equal to 0.5 Wt.%, and mixing the dried material with the fatty acid obtained by distillation in the step 1) to obtain the treated animal and vegetable oil.

The waste animal and vegetable oil is selected from one or more of acidified oil, illegal cooking oil, catering oil, vegetable fat, animal oil and animal fat.

The acidified oil is soybean acidified oil or palmitic acid oil.

The acid used for the acid treatment in the step 2) is an organic acid or an inorganic acid.

The organic acid or inorganic acid is phosphoric acid, citric acid, sulfuric acid or oxalic acid.

The water in the step 3) is primary water, the light absorption rate is 254nm, and the optical path of 1 cm: less than or equal to 0.001 and the conductivity less than or equal to 0.01 mS/m.

Has the advantages that: the metal and other impurities of the waste oil are high in content, so that the waste oil is not suitable for directly preparing liquid paraffin. The pretreatment method described in the present invention can remove impurities from oil, making it suitable as a raw material for preparing liquid paraffin. Compared with edible vegetable oil, the content of free fatty acid in the waste oil is higher and can reach 80 percent, so the method separates the free fatty acid part in the oil, and the impurities of the waste oil are concentrated in the oil product at the bottom of the distillation tower. And (3) carrying out next impurity removal treatment on the bottom oil of the distillation tower, and finally mixing the treated oil with the fatty acid part to obtain a final product. The method can greatly reduce the scale required by treatment equipment, saves investment, has high impurity concentration of the grease to be treated, is beneficial to the impurity removal chemical reaction, and has more optimized flow compared with the conventional vegetable oil refining process.

The method can remove metal ions, other elements and impurities in the animal and vegetable oil, reduces the phenomena of poisoning, hardening, coking and the like of the hydrogenation catalyst in the process of preparing the liquid paraffin after pretreatment, and ensures that the prepared liquid paraffin has high yield and good quality.

Drawings

FIG. 1 is a flow chart of animal and vegetable oil pretreatment for preparing liquid paraffin.

Detailed Description

The method of the present invention will be further described with reference to the accompanying drawings, but the invention is not limited thereto.