TWI637052B - Preparation method of biodiesel using microwave heater and diglycerin calcium - Google Patents

Abstract

A method for preparing biodiesel using microwave heater and diglycerin calcium comprises the following steps: step (a), preparing a transesterification reaction device, including a reaction tank and a microwave heater; and step (b), a component comprising a fat, an alcohol and a calcium diglyceride is placed in the reaction tank, and a heat treatment is performed by the microwave heater to perform a transesterification reaction to obtain a mixture; and step (c) The mixture is subjected to a purification treatment to obtain biodiesel.

Description

Preparation method of biodiesel using microwave heater and diglycerin calcium

The invention relates to a preparation method of biodiesel, in particular to a preparation method of biodiesel using a microwave heater and diglyceride to promote transesterification.

In order to avoid air pollution and the continuous expansion of the global warming phenomenon, and to effectively solve the problem of the lack of consumable energy, we must actively find and develop alternative renewable energy to meet the energy demand and mitigate the greenhouse effect on the environment and climate. The impact of biodiesel is a kind of renewable energy that is gradually being valued.

China National Petroleum Corporation, Vol. 38, No. 8, 2013 discloses a method for preparing raw diesel oil by catalyzing soybean oil with a solid base of glycerol. The method comprises the following steps: step (a), the waste egg shell is soaked in hot water for 24 hours and washed, dried at 120 ° C, and pulverized after drying. The pulverized egg shell was subjected to a calcination treatment at 900 ° C for 5 hours to obtain calcium oxide. Calcium oxide was mixed with glycerin and methanol in a volume ratio of 1:1 to form a mixed solution, and then the mixed solution was heated to reflux and reacted for 2 hours. Then, it was cooled to room temperature. Washing with methanol and drying at 120 ° C for 24 hours, followed by 4 hours of calcination at a predetermined temperature to obtain calcium diglyceride; step (b), placing soybean oil, methanol and calcium diglyceride In a reaction flask, and heated to reflux, and after a predetermined period of time, cooled to room temperature. Next, filtration is carried out to remove calcium diglyceride, and subjected to vacuum distillation to remove methanol, followed by a purification treatment to separate the raw diesel oil from the glycerol produced during the reaction. Although this method can obtain biodiesel, the production time is long and the conversion rate is low, which does not meet the needs of the industry.

In view of the above, the development of a method for preparing biodiesel with short production time and high conversion rate is an important goal of research and improvement of the present invention.

Accordingly, it is an object of the present invention to provide a method for producing biodiesel using a microwave heater and diglyceride calcium which has a short production time and a high conversion rate.

Therefore, the method for preparing the biodiesel of the present invention comprises the following steps: step (a), preparing a transesterification reaction device, comprising a reaction tank and a microwave heater; and step (b), comprising a grease, an alcohol And a component of calcium diglyceride [Ca(C ₃ H ₇ O ₃ ) ₂ ] is placed in the reaction tank, and a heat treatment is performed by the microwave heater to perform a transesterification reaction. And obtaining a mixture; in step (c), the mixture is subjected to a purification treatment to obtain biodiesel.

The effect of the invention is that the calcium diglyceride is used as a catalyst and the microwave heater is used to promote the progress of the transesterification reaction, effectively shortening the reaction time of the transesterification reaction and increasing the conversion rate, thereby being fast And a large amount of raw diesel is prepared.

The contents of the present invention will be described in detail below.

In the step (a), the reaction tank is not particularly limited as long as it can accommodate the component and does not react with the components of the component.

In the step (b), the microwave heater is used to heat the component contained in the reaction tank to promote the transesterification reaction. The microwave heater is for example but not limited to a domestic microwave oven or an industrial microwave reactor or the like. The transesterification reaction apparatus further includes a condenser disposed in the reaction tank. The condenser is used to condense alcohol which is volatilized during the heat treatment to reduce the loss of the alcohol, and has a water inlet for one water inlet and a water outlet for discharging the water. In order to provide a preferred conversion of the method for producing biodiesel of the present invention, preferably, the microwave heater has an operating power ranging from 50 watts to 600 watts. More preferably, the microwave heater operates at a power range of 200 watts to 400 watts.

In the step (b), the fats and oils may be used singly or in combination of plural kinds, and the oils and fats are, for example but not limited to, animal oil, vegetable oil or waste cooking oil, and the like. Based on the improvement of the reuse value of waste edible oil, the problem of disposal of waste edible oil, the environmental protection demand for sustainable use of resources, and the reduction of production cost, in the present embodiment, the fat is waste edible oil. The alcohols may be used singly or in combination of two or more, and the alcohols are, for example but not limited to, methanol (CH ₃ OH), ethanol (C ₂ H ₅ OH), propanol (C ₃ H ₇ OH) or butanol (C). ₄ H ₉ OH) and the like. In this embodiment, the alcohol is methanol. In order to provide a preferred conversion method for the preparation method of the biodiesel of the present invention, preferably, the molar ratio of the alcohol to the grease ranges from 5:1 to 9:1. More preferably, the molar ratio of the alcohol to the grease ranges from 6:1 to 9:1.

In the step (b), in order to make the preparation method of the biodiesel of the present invention have a better conversion rate, and in order to reduce the amount of the microgel produced by the saponification reaction during the transesterification reaction, Preferably, the diglycerin is used in an amount ranging from 1 part by weight to 3 parts by weight based on 100 parts by weight of the fat or oil. More preferably, the diglycerin calcium is used in an amount ranging from 1 part by weight to 2.5 parts by weight based on 100 parts by weight of the fat or oil.

In order to accelerate the progress of the transesterification reaction or to provide a preferred conversion of the method for producing the biodiesel of the present invention, in the step (b), the component further comprises activated carbon. In the step (b), in order to make the preparation method of the biodiesel of the present invention have a preferable conversion ratio, preferably, the amount of the activated carbon used is 0.5 in terms of the amount of the oil and fat used. Parts by weight to 2.5 parts by weight. More preferably, the activated carbon is used in an amount ranging from 0.5 part by weight to 1.5 parts by weight based on 100 parts by weight of the oil or fat.

In order to accelerate the progress of the transesterification reaction or to provide a preferred conversion of the method for producing the biodiesel of the present invention, in the step (b), the component further comprises water. Preferably, the water is used in an amount ranging from 0.5 part by weight to 2.5 parts by weight based on 100 parts by weight of the fat or oil. More preferably, the water is used in an amount ranging from 0.5 part by weight to 2 parts by weight based on 100 parts by weight of the fat or oil.

In order to provide a preferred conversion method for the preparation method of the biodiesel of the present invention, preferably, in the step (b), the reaction time of the transesterification reaction ranges from 10 minutes to 30 minutes. More preferably, in the step (b), the reaction time of the transesterification reaction ranges from 15 minutes to 30 minutes. In order to provide a preferred conversion method for the preparation method of the biodiesel of the present invention, preferably, in the step (b), the reaction temperature of the transesterification reaction ranges from 50 ° C to 70 ° C. More preferably, in the step (b), the reaction temperature of the transesterification reaction ranges from 55 ° C to 70 ° C.

In the step (c), since the mixture substantially contains unreacted substances (unreacted oils and unreacted alcohols), water, activated carbon, calcium diglyceride, biodiesel, and glycerin (C) ₃ H ₈ O ₃ ), therefore, the mixture is subjected to the purification treatment to obtain the biodiesel. The separation and purification treatment can be carried out by a generally known purification treatment, for example, by a centrifuge. In the present embodiment, the purification treatment is carried out using a centrifuge. In order to make the preparation method of the biodiesel of the present invention have better purification benefits, the operating speed of the centrifuge is in the range of 3500 rpm or more, and the centrifugation operation time of the centrifuge is more than 10 minutes.

The present invention will be further illustrated by the following examples, but it should be understood that this embodiment is intended to be illustrative only and not to be construed as limiting.

Preparation Example 1 Calcium diglyceride

Providing a reaction apparatus for preparing the calcium diglyceride, and the reaction apparatus comprises a reaction tank, a constant temperature water tank for heating the reaction tank, a stirrer disposed in the reaction tank, and a condensation installed in the reaction tank Device. 9 grams of calcium oxide, 132 grams of methanol, and 30 grams of glycerin were placed in the reaction tank. The reaction vessel was placed in a constant temperature water bath set at a temperature of 60 °C. The calcium oxide, methanol, and glycerin were agitated by a stirrer, and the reaction was carried out at the temperature, wherein the stirrer was operated at 3000 rpm, and the reaction time was 3 hours. The color of the solution is then observed, and when the color changes to a pale yellow color, the reaction is completed. Then, the pale yellow solution was subjected to a purification treatment in a centrifuge (label: HERMLE; model: Z200A), wherein the centrifuge was operated at a rotational speed of 4000 rpm, and the centrifugation operation time of the centrifuge was 5 minutes. The upper layer solution was then poured out and the lower layer of the precipitate was taken out. Then, the precipitate was washed twice with methanol and placed in a vacuum dryer for 8 hours of drying.

Example 1 Biodiesel

Providing a transesterification reaction device for preparing the biodiesel, and the transesterification reaction device comprises a reaction tank, a microwave heater (label: alum technology; model: XO-SM50), and a The condenser of the reaction tank. 1 g of calcium diglyceride of Preparation Example 1, 17.91 g of methanol and 100 g of waste cooking oil (average molecular weight of 893.34, saponification price of 188.395, soybean oil (label: uniform) after frying squid The waste oil) is placed in the reaction tank, wherein the molar ratio of the methanol to the waste cooking oil is 5:1. The reaction vessel was placed in a microwave heater set at a power of 500 watts. The diglycerin calcium, the methanol and the waste edible oil were subjected to a stirring treatment using a built-in magnetic stirrer, and the reaction was carried out at the temperature to form a mixture, and the reaction time of the transesterification reaction was 20 minutes. The mixture was then subjected to a purification treatment in a centrifuge (label: HERMLE; model: Z200A) to obtain a crude product containing biodiesel.

Examples 2 to 33

Examples 2 to 33 were prepared in the same manner as in Example 1 except that the difference was shown in Table 1.

Evaluation project

Conversion rate (unit: %): The biomass diesel content in the crude product containing biodiesel of Examples 1 to 33 was analyzed using a gas chromatograph (Model: Perkin Elmer GC Clarus 600) and passed through the formula (1). Calculate the conversion rate. 0.5 g of crude product containing biodiesel, 0.05 g of methyl laurate standard and 10 ml of n-hexane were mixed to form a test article. 1 μL of the test article was injected into the gas chromatograph for analysis. The setting conditions of the gas chromatograph are: injection port temperature is 280 ° C, nitrogen flow rate is 45 mL / min, air flow rate is 450 mL / min, split ratio is 1:20, flame ionization detector The temperature was 300 °C and the temperature ramp was maintained at 210 °C for 4 minutes, then the temperature was raised to 240 °C at 4 °C/min for 8 minutes. The formula (1) is a conversion ratio = [(integrated area of biodiesel / integral area of methyl laurate) × weight of methyl laurate] × 100% / weight of crude product containing biodiesel.

Average molecular weight of fats and oils: Calculated using equation (2). The formula (2) is (3 × 56.1 × 1000) / saponification price, wherein the 56.1 is the molecular weight of potassium hydroxide.

Table 1

In summary, the diglyceride calcium is used as a catalyst and the microwave heater is used to promote the transesterification reaction, thereby effectively shortening the reaction time of the transesterification reaction and increasing the conversion rate, thereby enabling rapid and The production of biodiesel is carried out in large quantities, so that the object of the present invention can be achieved.

However, the above is only the embodiment of the present invention, and the scope of the invention is not limited thereto, and all the simple equivalent changes and modifications according to the scope of the patent application and the patent specification of the present invention are still Within the scope of the invention patent.

Claims (9)

A method for preparing biodiesel using microwave heater and diglycerin calcium comprises the following steps: step (a), preparing a transesterification reaction device, including a reaction tank and a microwave heater; and step (b), A component containing water, fat, alcohol, and calcium diglyceride is placed in the reaction tank, and the amount of the water is from 1 part by weight to 2 parts by weight based on 100 parts by weight of the oil. And the microwave heater is subjected to a heat treatment to carry out a transesterification reaction to obtain a mixture; in the step (c), the mixture is subjected to a purification treatment to obtain a biomass diesel oil. The method for preparing a biomass diesel fuel using a microwave heater and diglycerin calcium according to claim 1, wherein the microwave heater has an operating power ranging from 50 watts to 600 watts. The method for producing a biodiesel using a microwave heater and diglycerin calcium according to claim 1, wherein the oil is selected from the group consisting of waste cooking oil. The method for producing a biodiesel using a microwave heater and diglycerin calcium according to claim 1, wherein the alcohol is selected from the group consisting of methanol, ethanol, propanol, butanol, or any combination thereof. The method for producing a biodiesel using a microwave heater and diglycerin calcium according to claim 1, wherein the amount of the diglyceride is from 1 part by weight to 100 parts by weight of the oil or fat. 3 parts by weight. The method for preparing a biomass diesel oil using a microwave heater and diglycerin calcium according to claim 1, wherein the ratio of the molar ratio of the alcohol to the grease is 5:1. Until 9:1. The method for producing biodiesel using a microwave heater and diglycerin calcium according to claim 1, wherein the reaction time of the transesterification reaction ranges from 10 minutes to 30 minutes. The method for producing a biodiesel using a microwave heater and diglycerin calcium according to claim 1, wherein the reaction temperature of the transesterification reaction ranges from 50 ° C to 70 ° C. The method for preparing a biomass diesel oil using a microwave heater and diglycerin calcium according to claim 1, wherein the component further comprises activated carbon, and the activated carbon is used in an amount of 100 parts by weight of the activated carbon. The amount used is in the range of 0.5 part by weight to 2.5 parts by weight.