CN1279136C - Method for preparing high-strength binder from vegetable oil residue - Google Patents

Abstract

The invention discloses a method for preparing a binder by using vegetable oil residues, which is a method for preparing high-strength binders from vegetable oil residues with simple preparation process, high binder strength and good process performance. The present invention is to put the vegetable oil asphalt into the reaction chamber, preheat it to 150-270°C, then add the esterification agent while stirring, continue to stir for 2-5 hours, cool to 180-200°C, pour into the cooling barrel, continue to stir, and cool When it reaches room temperature or 80°C to 50°C, it can be finished in barrels. The invention has the following advantages: ① The product has high strength and good comprehensive performance. It can replace expensive tung oil or some resins to make grade I cores, which is unmatched by synthetic fat oil and unmodified vegetable oil binders. ②The cost is low, the price is only equivalent to 1/3 of tung oil, and the economic benefits are considerable. ③ Meet environmental protection requirements. The raw material is the residue of refining edible oil, and the esterification agent is also non-toxic. After chemical analysis of the manufactured binder, no toxic elements are found.

Description

Method for preparing high-strength binder from vegetable oil residue

Technical field:

The invention relates to a method for preparing a binder, in particular to a method for preparing a binder using vegetable oil residue.

Background technique:

Foundry binders are basically divided into three categories: resins, oils, and inorganic salts. Currently, inorganic salts and resins are generally used. Inorganic salts: mainly used in steel castings, such as water glass, accounting for about 10% of the total binder. Resin: More than 90% of the adhesives in developed countries use this type of adhesive. In my country, the amount has increased rapidly in the past ten years, but its price is expensive, and it needs supporting equipment and technological measures when using it. The amount is 30% to 40%. Oil binder: mainly synthetic fat oil (not produced now) that has been used in the 1960s and the residue of vegetable oil distillation developed in the 1980s (also known as vegetable oil asphalt). The performance of these two binders is similar , the source of raw materials is abundant, the price is low, it is easy to make cores, and the strength and moisture absorption resistance of the cores are very good. Many large and medium-sized foundries are still widely used, but the dry strength of this type of binder is not high, and it is limited to below grade II. Ni core, at present some factories want to make I level Ni core, still use tung oil or resin sand.

Vegetable oil residues are currently sold in the market as binders of about thousands of tons, but they are not modified and are directly mixed with kerosene. Therefore, there are great defects in strength and process performance, and it cannot be used for the production of high-grade Ni cores. After research, the modification of this kind of binder and its dry strength reach the strength of tung oil (about 3-3.5Mpa), the process performance is better than that of tung oil, and the cost is lower than that without modification, only 1/3 of the price of tung oil.

Utility model content:

The invention solves the defects that the existing vegetable oil asphalt is directly used as a binder without modification, resulting in low strength, poor process performance, and cannot be used for the production of high-grade cores, and provides a binder with simple preparation process and A method for preparing a high-strength binder from vegetable oil residues with high strength and good process performance.

Technical scheme of the present invention is as follows:

1. Put vegetable oil asphalt into the reaction chamber and preheat to 150-270°C.

2. When the heating temperature is guaranteed to be 250-300°C, gradually add the esterification agent while stirring, and continue stirring for 2-5 hours to make the materials fully react and mix evenly; then cool to 180-200°C.

3. Pour into the cooling barrel, continue to stir, and cool to room temperature or 80°C to 50°C, then the finished product can be filled into barrels.

Advantage of the present invention has:

①The product has high strength and good comprehensive performance. It can replace expensive tung oil (8,000 yuan/T) or some resins (13,000 yuan/T) to manufacture grade I cores, which is unmatched by synthetic fat oil and unmodified vegetable oil binders.

②Low cost. The esterifying agent adopts a low-priced comprehensive esterifying agent that turns waste into treasure. For example, the existing esterification agents include glycerin, pentapentyl alcohol, and ethylene glycol. These chemical raw materials cost more than 6,000 yuan per ton, but now the black waste silk (block) from chemical fiber factories is about 1,000 yuan/T～1,500 yuan/ton T. Example: The vegetable oil asphalt on the market is about 2000 yuan/T. Assuming that the ratio of vegetable oil asphalt and esterifying agent is 8:2, the binder produced per ton can be reduced by 200 yuan (compared to the vegetable oil asphalt binder used directly without modification), and for the use of this binder As far as the factory using tung oil is concerned, if tung oil was originally used to manufacture the I-level core, and now this binder is used (the price is only equivalent to 1/3 of tung oil), the economic benefits are quite considerable.

③ Meet environmental protection requirements. The raw material is the residue of refining edible oil, and the esterification agent is also non-toxic. After chemical analysis of the manufactured binder, no toxic elements are found.

Detailed ways:

(1) The source of raw vegetable oil asphalt: it is the soapstock of rapeseed oil, soybean oil, and cottonseed oil after four deacidification (deacidification, detoxification, decolorization, degumming), acidification, hydrolysis to obtain mixed fatty acids, and then distillation All kinds of oleic acid and erucic acid are produced, and the remaining material is vegetable oil asphalt. Vegetable oil asphalt is in the form of paste, and the waste from different factories—vegetable oil asphalt has different viscosities.

(2) The vegetable oil asphalt modification process method is as follows:

(a) Process route:

① Loading: Put vegetable oil asphalt of various viscosities into the reaction chamber and preheat it to 150-270°C.

② Gradually add the esterifying agent while the heating temperature is kept at 250-300°C and stirring continuously, and the weight ratio of vegetable oil asphalt and esterifying agent is 8-9; 2-1.

Winter: The ratio of vegetable oil asphalt to esterification agent is 9:1;

Summer: The ratio of vegetable oil asphalt to esterification agent is 8:2;

Spring and autumn: the ratio of vegetable oil asphalt to esterification agent is 85:15;

③Continue stirring for 2-5 hours to make the materials fully react and mix evenly; then cool to 180-200°C.

④ Pour the cooled product into the cooling barrel, continue to stir, and let it cool down to room temperature or 80°C to 50°C, then it can be packed into a barrel to become a finished product.

(b) Esterifying agent: also known as modifier. It can be polyester waste, such as: polyester, polypropylene, acrylic waste silk, blocks, cloth scraps, waste foam, beverage bottles with trademark colors, etc. These waste materials, especially colored waste materials, are processed by chemical fiber factories at a low price (generally 1-2 thousand yuan/ton). As a vegetable oil asphalt esterification agent, it is turning waste into treasure. This is also one of the key points of the present invention's patent application.

(c) Modification principle: Because there are a large amount of free fatty acids in the vegetable oil asphalt, the acid value is relatively high, ranging from about 40 to 60, the iodine value is about 40 to 50, and the saponification value is about 100, so after adding the modifier, At high temperature, the modifier decomposes and breaks the chain into ethylene glycol and terephthalic acid, and carries out the dehydration reaction of carboxyl and hydroxyl groups. The reaction formula is as follows:

Due to the complex composition of vegetable oil asphalt, it is impossible to react in one direction, but the general reaction tends to change from small molecules to large molecules, from linear to network, from non-conjugated double bonds to conjugated double bonds, and then to make the bonding after modification The strength of the agent is greatly improved, and the comprehensive properties such as surface tension, adhesion and dryness are improved.

The product is mainly used in foundries as a bonding agent for cores.

The viscosity value of the binder is adjusted with kerosene according to the requirements of each factory.

(3) How to use the product

①Use: A diesel engine cylinder head (grade I core) in a factory used to make sand cores with tung oil, but now uses this binder. Its performance indicators are: dry strength 3.0MPa, viscosity (N-6, 25°C) 200～250S , The amount of binder added is 3 to 4%, which varies according to the situation of silica sand. The drying temperature is 220°C, and the holding time depends on the specific situation.

②Sand mixing process:

Sand (100%) + binder (3% ~ 3.5%) + clay (1%)

Sand mixing time > 10 minutes, depending on the situation of each factory.

This product is a black viscous liquid, packed in barrels. It is the same as the conventional fat-forming process, and there is no need to add or modify old equipment and tooling. The technical operation is the same as Hezhi, and everyone from technicians to workers will operate skillfully.

Claims (4)

1, a kind of method of utilizing vegetable oil dregs to prepare high-strength adhesive is characterized in that:

1. plant oil asphalt is packed in the reaction chamber, be preheated to 150-270 ℃;

2. guaranteeing that Heating temperature is under 250-300 ℃ the situation, progressively add esterifying agent while stirring, keep and stir 2-5h, be cooled to 180-200 ℃ then;

3. inject cooling tank, continue to stir, be cooled to room temperature or 80 ℃～50 ℃, can the barrelling finished product.

2, vegetable oil dregs according to claim 1 prepares the method for high-strength adhesive, it is characterized in that: the weight proportion of plant oil asphalt and esterifying agent is 8-9: 2-1.

3, vegetable oil dregs according to claim 1 and 2 prepares the method for high-strength adhesive, it is characterized in that: described esterifying agent comprises polyester waste material.

4, vegetable oil dregs according to claim 3 prepares the method for high-strength adhesive, it is characterized in that: described esterifying agent comprises: the waste silk of terylene, polypropylene fibre, acrylic, piece, buckram corner piece material, and the beverage bottle of waste foam, band trade mark color.