阅读说明：本技术 离子液体条件下新型介孔分子筛的制备及催化裂解制备高质量富烃液体燃料油的方法 (Preparation of novel mesoporous molecular sieve under ionic liquid condition and method for preparing high-quality hydrocarbon-rich liquid fuel oil by catalytic cracking ) 是由 王志萍 尚亚琼 李露 崔学旺 于世涛 于 2021-09-26 设计创作，主要内容包括：本发明涉及一种以离子热法一步合成新型介孔分子筛以及将其作为催化剂催化裂解餐厨废弃油脂制备高质量富烃液体燃料油的方法,其特征是采用自制的咪唑类离子液体[Bmim]Br、[Bmim]Cl、[Hmim]Br、[Hmim]Cl或[Pmim]Cl,一步法合成新型介孔分子筛BMB-11、BMC-13、HMB-12、HMC-10、PMC-10,以及新型碱性介孔分子筛K-BMC-13、Ca-BMC-13、Mg-BMC-13。分别采用所合成的分子筛为催化剂,在380-440℃下对餐厨废弃油脂进行催化裂解反应,餐厨废弃油脂的裂解率可达84.8％,液体燃料油的收率可达62.8％,产物的主要成分分布在C-(14)～C-(18)之间,所得燃料油的性能指标与0号柴油相当。所用的Mg-BMC-13催化剂具有良好的使用寿命。(The invention relates to a method for preparing high-quality hydrocarbon-rich liquid fuel oil by one-step synthesis of a novel mesoporous molecular sieve by an ionothermal method and catalytic cracking of kitchen waste grease by using the mesoporous molecular sieve as a catalyst, which is characterized in that self-made imidazole ionic liquid [ Bmim ] is adopted]Br、[Bmim]Cl、[Hmim]Br、[Hmim]Cl or [ Pnim]Cl, synthesizing novel mesoporous molecular sieves BMB-11, BMC-13, HMB-12, HMC-10 and PMC-10 by a one-step method, and novel alkaline mesoporous molecular sieves K-BMC-13, Ca-BMC-13 and Mg-BMC-13. The synthesized molecular sieve is respectively adopted as a catalyst to carry out catalytic cracking reaction on the kitchen waste grease at the temperature of 380-440 ℃, the cracking rate of the kitchen waste grease can reach 84.8 percent, the yield of the liquid fuel oil can reach 62.8 percent, and the main components of the product are distributed in C 14 ～C 18 The performance index of the obtained fuel oil is equivalent to that of No. 0 diesel oil. The Mg-BMC-13 catalyst usedHas good service life.)

1. A one-step synthesis method is adopted, under the condition of imidazole ionic liquid, raw materials are mixed according to a certain proportion, and the molecular self-assembly effect among the ionic liquid, various silicon sources and various water-soluble metal salts is utilized to synthesize novel mesoporous molecular sieves BMB-11, BMC-13, HMB-12, HMC-10 and PMC-10, as well as novel alkaline mesoporous molecular sieves K-BMC-13, Ca-BMC-13 and Mg-BMC-13. The synthesized molecular sieve has characteristic diffraction peak of mesoporous molecular sieve, and has good long-range order and crystallinity.

2. The synthesized mesoporous molecular sieve is used as a catalyst to crack the high-acid-value kitchen waste grease to prepare the high-quality hydrocarbon-rich liquid fuel oil. Mixing kitchen waste oil and fat with molecular sieve catalyst (BMB-11, BMC-13, HMB-12, HMC-10, PMC-10, or K-BMC-13, Ca-BMC-13, Mg-BMC-13) according to m_{Kitchen waste grease}:m_{Catalyst and process for preparing same}Adding the mixture into a reaction kettle in a ratio of 50: 1-20: 1, and performing catalytic cracking at the temperature of 380-440 ℃. The generated steam is condensed to obtain a dark yellow liquid product, and the catalyst can be directly recycled without any treatment. The liquid fuel oil product obtained by cracking is mainly C₁₄～C₁₈The linear hydrocarbon compound of (1).

Technical Field

The invention belongs to the technical field of biomass energy conversion, and mainly relates to a method for preparing high-quality hydrocarbon-rich liquid fuel oil by one-step synthesis of a novel mesoporous molecular sieve by an ionothermal method and catalytic cracking of kitchen waste grease by using the mesoporous molecular sieve as a catalyst.

Background

The biomass becomes a hot point of research in recent years because the biomass can be directly converted into novel renewable easily-degradable liquid fuel oil, and a high-temperature pyrolysis method is regarded as one of the most promising methods in the aspect of producing high-quality liquid biomass fuel oil at present, and the key point of the method is the design, preparation and selection of a high-efficiency catalyst. The microporous molecular sieve is the catalyst most studied in the catalytic cracking of the biomass oil at present, but is limited by the aperture of the microporous molecular sieve, the molecular weight distribution of the product obtained by cracking is narrow, and most of the product is concentrated on C₁₀Low molecular weight products, low liquid product yield, high catalyst coking rate, short life, and poor regeneration performance (Journal of Analytical Applied Pyrolysis,2004,71(2): 987-. The mesoporous molecular sieve has a one-dimensional open pore structure, is easy to load acid-base oxides as a carrier, has certain acidity and alkalinity, and has obvious advantages for catalyzing macromolecular compounds. However, the template agent used in the hydrothermal method is expensive and not suitable for industrial production, the diameter modulation range of the synthesized Mesoporous molecular sieve is too small, deep catalytic cracking cannot be performed when heavy oil is catalytically treated, the catalyst has poor stability and is easy to be carbonized and inactivated, and the obtained liquid fuel has low yield and high acid value (microporus and mesopore Materials,2013,175: 125-. The ionic liquid has the advantages of low vapor pressure, designable structure, adjustable property, good solubility, high thermal stability and the like, has various types, and can be used as a solvent and a structure directing agent. The method is favorable for firm bonding of heteroatom metal salt and silicon-oxygen bonds in the ionic liquid environment, and greatly shortens the preparation time of the molecular sieve. Through the molecular self-assembly effect among the ionic liquid, various silicon sources and water-soluble metal salt with strong base center, a novel alkaline mesoporous molecular sieve (ACS Sustainable Chemistry and Engineering,2016,4: 5594-. Therefore, the research of the novel catalyst has great significance for preparing the liquid fuel oil by the thermal cracking method.

Disclosure of Invention

In order to solve the defects of poor catalytic effect, poor stability and easy coking of the prior mesoporous molecular sieve, poor quality, low yield, low selectivity, high acid value and the like of pyrolysis oil obtained by catalytically pyrolyzing biomass oil, the invention provides a method for preparing high-quality hydrocarbon-rich liquid fuel oil by synthesizing a novel mesoporous molecular sieve in one step by an ionothermal method and catalytically pyrolyzing kitchen waste grease by taking the mesoporous molecular sieve as a catalyst₁₄～C₁₈The straight-chain hydrocarbon compound accounts for more than 70 percent of the total liquid product, has stable performance, and the catalyst can be repeatedly used.

The biological oil adopted by the invention is kitchen waste oil with an acid value of 170mgKOH g^-1。

The ionic liquid used in the invention is a self-product, and is synthesized under the microwave condition, and the synthesis method comprises the following steps:

weighing N-methylimidazole and N-butyl bromide (molar ratio is N (N-methylimidazole): N (N-butyl bromide) ═ 1:1.3), adding into a three-neck flask, placing into a microwave solid-liquid phase synthesis workstation with a reflux condenser tube, and reacting for 5min at 100 ℃. And after the reaction is finished, washing the obtained light yellow viscous liquid with ethyl acetate, transferring the light yellow viscous liquid to a rotary evaporator, and evaporating unreacted substances to obtain the ionic liquid [ Bmim ] Br.

N-methylimidazole and N-butyl chloride (molar ratio is N (N-methylimidazole): N (N-butyl chloride) ═ 1:1.1) are weighed and added into a three-neck flask, and the three-neck flask is placed in a microwave solid-liquid phase synthesis workstation with a reflux condenser tube to react for 50min at 100 ℃. And after the reaction is finished, washing the obtained light yellow viscous liquid with ethyl acetate, transferring the light yellow viscous liquid to a rotary evaporator, and evaporating unreacted substances to obtain the ionic liquid [ Bmim ] Cl.

Weighing N-methylimidazole and N-bromo-N-hexane (molar ratio is N (N-methylimidazole): N (bromo-N-hexane) ═ 1:1.1) and adding into a three-neck flask, placing into a microwave solid-liquid phase synthesis workstation with a reflux condenser tube, and reacting for 24min at 80 ℃. And after the reaction is finished, washing the obtained light yellow viscous liquid with ethyl acetate, transferring the light yellow viscous liquid to a rotary evaporator, and evaporating unreacted substances to obtain ionic liquid [ Hmim ] Br.

Weighing N-methylimidazole and N-chlorohexane (molar ratio is N (N-methylimidazole): N (chlorohexane): 1:1.1) and adding into a three-neck flask, placing into a microwave solid-liquid phase synthesis workstation with a reflux condenser tube, and reacting for 50min at 100 ℃. And after the reaction is finished, washing the obtained light yellow viscous liquid with ethyl acetate, transferring the light yellow viscous liquid to a rotary evaporator, and evaporating unreacted substances to obtain the ionic liquid [ Hmim ] Cl.

N-methylimidazole and N-pentane chloride (molar ratio is N (N-methylimidazole): N (N-pentane chloride): 1:1.2) are weighed and added into a three-neck flask, and the three-neck flask is placed in a microwave solid-liquid phase synthesis workstation with a reflux condenser tube to react for 50min at 75 ℃. And after the reaction is finished, washing the obtained light yellow viscous liquid with ethyl acetate, transferring the light yellow viscous liquid to a rotary evaporator, and evaporating unreacted substances to obtain the ionic liquid [ Pnim ] Cl.

The novel mesoporous molecular sieve catalyst used in the invention is a self-product, and the synthesis method comprises the following steps:

adding 15 g of ionic liquid [ Bmim ] Br (or [ Bmim ] Cl, or [ Hmim ] Br, or [ Hmim ] Cl, or [ Pnim ] Cl) into a three-neck flask, sequentially adding 11.86g of tetraethylammonium hydroxide, 10.8g of silicon dioxide solution, 0.1076g of sodium hydroxide and 0.147 g of sodium metaaluminate every 30 minutes, uniformly mixing, heating to 80 ℃, reacting for 3 hours, transferring into a crystallization kettle after the reaction is finished, crystallizing for 1 hour at 180 ℃ in an oven, cooling, performing suction filtration, washing to be neutral, drying, and roasting for 8 hours at 550 ℃ to obtain finished products of the mesoporous molecular sieves, namely BMB-11, BMC-13, HMB-12, HMC-10 and PMC-10.

According to the above method, an ionic liquid [ Bmim ] is used]Cl, and adding KCl (or CaCl) into the solution₂Or MgSO (MgSO)₄) In a molar ratio of n (KCl or CaCl)₂Or MgSO (MgSO)₄)/n(SiO₂)/n(Na₂O)/n(TEAOH)/n(H₂O) ═ 2.0/60/2.5/22/800, mixing uniformly, heating to 80 deg.C, reacting for 3 hr, after reaction, transferring into crystallizing still, placing in oven for 180 deg.C crystallization for 1 hr, cooling, suction filtering, washing to neutrality, drying, roasting at 550 deg.C for 8 hr, synthesizing new type alkaline mesoporousMolecular sieve K-BMC-13, Ca-BMC-13 and Mg-BMC-13.

Effects of the invention

1. Novel mesoporous molecular sieves BMB-11, BMC-13, HMB-12, HMC-10 and PMC-10, novel alkaline mesoporous molecular sieves K-BMC-13, Ca-BMC-13 and Mg-BMC-13 are synthesized by adopting ionic liquids [ Bmim ] Br, [ Bmim ] Cl, [ Hmim ] Br, [ Hmim ] Cl or [ Pnim ] Cl through a one-step method.

2. The novel mesoporous molecular sieve is used as a catalyst, the catalytic performance is stable, the specific shape selection selectivity of the novel mesoporous molecular sieve can be utilized to generate liquid fuel oil with narrow molecular weight distribution when the novel mesoporous molecular sieve is used for catalyzing the cracking of high-acid-value kitchen waste oil, and the main component of the fuel oil is distributed in C₁₄～C₁₈In the meantime. The highest cracking rate of the kitchen waste grease can reach 84.8 percent, the highest yield of the liquid fuel oil can reach 62.8 percent, and C in the product₁₄～C₁₈The straight-chain hydrocarbon compound accounts for more than 70 percent, the obtained liquid fuel oil has low acid value, and the performance index of the liquid fuel oil is equivalent to that of No. 0 diesel oil.

3. The synthesized mesoporous molecular sieve has strong thermal stability and good reusability.

4. The liquid fuel oil obtained by catalytic cracking and No. 0 diesel oil can be mutually soluble in any proportion.

Detailed Description

The following examples are further illustrative, but not limiting, of the scope of the invention.

Example 1:

preparation of BMB-11 catalyst: adding 15 g of ionic liquid [ Bmim ] Br into a three-neck flask, sequentially adding 11.86g of tetraethylammonium hydroxide, 10.8g of silicon dioxide solution, 0.1076g of sodium hydroxide and 0.147 of sodium metaaluminate every 30 minutes, uniformly mixing, heating to 80 ℃, reacting for 3 hours, transferring into a crystallization kettle after the reaction is finished, placing into an oven for 180 ℃ crystallization for 1 hour, cooling, performing suction filtration, washing to neutrality, drying, and roasting for 8 hours at 550 ℃ to obtain a molecular sieve finished product BMB-11 for later use.

10g of kitchen waste grease and 0.33g of catalyst BMB-11 are added into a reactor with a condenser tube and a thermometer. Heating to 430 ℃ and keeping the temperature for reaction for 100 min. The cracking rate was 81.4%, the yield of liquid product was 55.6%, the yield of gaseous product was 25.8% and the yield of residue was 18.6%.

Example 2:

preparing a BMC-13 catalyst: the preparation conditions and procedure were the same as in example 1 except that the ionic liquid [ Bmim ] Br was changed to [ Bmim ] Cl.

The experimental conditions and procedures were the same as those of example 1 except that the catalyst BMB-11 was changed to the catalyst BMC-13, the cleavage rate was 81.3%, the yield of the liquid product was 54.4%, the yield of the gaseous product was 26.9%, the yield of the residue was 18.7%, and the acid value of the liquid oleic acid obtained by cleavage was 40.2 mgKOH. g^-1。

Example 3:

preparation of HMB-12 catalyst: the preparation conditions and procedure were the same as in example 1 except that the ionic liquid [ Bmim ] Br was changed to [ Hmim ] Br.

The experimental conditions and procedure were the same as in example 1 except that catalyst BMB-11 was changed to catalyst HMB-12, the cracking rate was 76.4%, the liquid product yield was 58.7%, the gaseous product yield was 17.7%, and the residue yield was 17.5%.

Example 4:

preparation of HMC-10 catalyst: the preparation conditions and procedure were the same as in example 1 except that the ionic liquid [ Bmim ] Br was changed to [ Hmim ] Cl.

The experimental conditions and procedures were the same as in example 1 except that catalyst BMB-11 was changed to catalyst HMC-10, the cracking rate was 80.6%, the liquid product yield was 57.6%, the gaseous product yield was 23.0%, and the residue yield was 19.4%.

Example 5:

preparation of PMC-10 catalyst: the preparation conditions and procedure were the same as in example 1 except that the ionic liquid [ Bmim ] Br was changed to [ Pnim ] Cl.

The experimental conditions and procedures were the same as those of example 1 except that catalyst BMB-11 was changed to catalyst PMC-10, the cleavage rate was 77.7%, the yield of liquid product was 57.2%, the yield of gaseous product was 20.5%, the yield of residue was 22.3%, and the acid value of liquid oleic acid obtained by cleavage was 44.3 mgKOH. g^-1。

Example 6:

preparation of K-BMC-13 catalyst: the preparation conditions and the steps are the same as those of the example 2, except that KCl is added in the synthesis process, and the molar ratio is n (KCl)/n (SiO)₂)＝1.0/30。

The experimental conditions and procedures were the same as in example 1 except that the catalyst BMB-11 was changed to the catalyst K-BMC-13, the cracking rate was 83.9%, the yield of the liquid product was 62.8%, the yield of the gaseous product was 21.1%, and the yield of the residue was 16.1%.

Example 7:

preparation of Ca-BMC-13 catalyst: the preparation conditions and steps are the same as example 2, except that CaCl is added during the synthesis₂The molar ratio is n (CaCl)₂)/n(SiO₂)＝1.0/30。

The experimental conditions and procedures were the same as in example 1 except that the catalyst BMB-11 was changed to the catalyst Ca-BMC-13, the cracking rate was 79.5%, the yield of the liquid product was 53.2%, the yield of the gaseous product was 26.3%, and the yield of the residue was 20.5%.

Example 8:

preparing a Mg-BMC-13 catalyst: the preparation conditions and procedure were the same as in example 2, except that MgCl was added during the synthesis₂The molar ratio is n (MgCl)₂)/n(SiO₂)＝1.0/30。

The experimental conditions and procedures were the same as in example 1 except that the catalyst BMB-11 was changed to the catalyst Mg-BMC-13, the cracking rate was 84.8%, the yield of the liquid product was 62.8%, the yield of the gaseous product was 22.0%, and the yield of the residue was 15.3%.

Example 9:

the experimental conditions and procedures were the same as in example 1 except that the catalyst was changed to the catalyst recovered in example 8, and the recycling experiment was carried out five times. The catalyst reuse results are shown in table 1.

TABLE 1 reuse results of Mg-BMC-13