Sulfur pre-dispersion organic treatment process

Abstract

The invention relates to a sulfur pre-dispersion organic treatment process, which comprises the following steps: adding natural latex into a stirring kettle, adding pure water with the weight ten times that of the natural latex, diluting, adding a dispersing agent, and uniformly stirring to form latex; then adding sulfur powder, fully stirring to a uniform state, and then adding an acetic acid solution for acidification and solidification; a mixture obtained after acidification and solidification is filtered through a filter screen for solid-liquid separation, a solid obtained after solid-liquid separation is dried to remove moisture, and a sulfur powder latex pre-dispersion product is obtained. The sulfur main body content can be increased to 95% or above, the process technology is environmentally friendly and efficient, continuous production can be achieved, the productivity is large, energy consumption is low, and environmental protection and cleanness are achieved. After the content of the main body sulfur powder is increased, the use amount can be reduced and the cost can be reduced in the actual application process of customers compared with the previous 80% master batch particles. The rubber content is greatly reduced compared with that of the conventional product, so that the chemical deterioration of the product can be effectively prevented, the effective shelf life is prolonged, and the rubber product processing process and the product quality are not influenced by side effects.

Description

Technical Field

[0001] The invention relates to the technical field of pre-dispersion treatment of rubber functional additives. Background Art

[0002] Pre-dispersed rubber additives, also often called rubber additive masterbatch or pre-dispersed masterbatch, are not only an upgrade of traditional rubber additives, but also because of their dust-free and easy-to-disperse properties, they perform well in automatic weighing and continuous low-temperature mixing, effectively improving mixing efficiency and storage stability. Therefore, they have been widely used in rubber products.

[0003] The production process of pre-dispersed rubber additives primarily involves internal mixing, open mixing, filtration, granulation, and packaging. In the internal mixer, the rubber compound undergoes internal mixing to produce a base rubber. Accelerators and auxiliary materials are then added and internally mixed again. After the open mixer rolls are adjusted to the appropriate pitch, the material is open-mixed, filtered, and granulated. Finally, the granulated product is cooled, weighed, divided, and packaged to produce the finished product.

[0004] Sulfur, a leading rubber vulcanizer, is often added during the final mixing stage. However, ordinary sulfur powder poses safety risks due to its flammability and explosion, and its transportation and application are inconvenient. Furthermore, its dispersion speed and uniformity during the rubber mixing process are difficult to meet requirements. Therefore, pre-dispersed rubber additives obtained by pre-dispersing sulfur play a crucial role in the rubber products industry.

[0005] Existing sulfur rubber pre-dispersion technology mainly involves mixing sulfur powder with synthetic rubber such as styrene-butadiene and EPDM, kneading the rubber in proportion, and then cutting into pellets to produce masterbatch particles with an 80% sulfur content. However, its main sulfur content is low, the processing cost is high, the output is low, and it is easy to fail due to chemical reactions. Summary of the Invention

[0006] In view of the above situation, the present invention proposes a sulfur pre-dispersion organic treatment process, which comprises adding a natural latex liquid into a stirring tank, adding ten times the weight of pure water to dilute it, adding a dispersant and stirring evenly to form a latex liquid; then adding sulfur powder, stirring thoroughly until it is uniform, and then adding acetic acid solution for acidification and coagulation; filtering the mixture obtained after acidification and coagulation through a filter screen for solid-liquid separation, and subjecting the solid obtained after solid-liquid separation to a drying step to remove moisture, thereby obtaining a sulfur powder latex pre-dispersion product.

[0007] Furthermore, the dispersant is a sodium polycarboxylate dispersant, and the weight of the dispersant is 5‰ of the weight of the natural latex.

[0008] Furthermore, the solid obtained after the solid-liquid separation is subjected to a drying step to remove moisture until the water content is less than 1%.

[0009] Preferably, the solid obtained after the solid-liquid separation enters a conveyor belt, and during the operation of the conveyor belt, it passes through a drying room with flash evaporation to remove the remaining moisture.

[0010] Preferably, the solid obtained after the solid-liquid separation is subjected to a drying step to remove moisture, and then pressed into blocks by extrusion molding, and then cut into sheet or granular products by a slicer or pelletizer.

[0011] Preferably, the natural latex liquid is a natural latex liquid with a solid content of 5%.

[0012] Preferably, the adding of acetic acid solution for acidification and coagulation is adding acetic acid solution with a weight percentage of 5% of natural latex.

[0013] Furthermore, the water obtained after the solid-liquid separation is returned to the circulating water pool for reuse.

[0014] Preferably, a sulfur pre-dispersion organic treatment process is provided, wherein 100 kg of natural latex liquid with a solid content of 5% is added to a 3000L stirring kettle, and then 1000 kg of pure water is added to dilute it, and then a dispersant with a weight of 5‰ of natural latex is added and stirred evenly to form a latex; then 950 kg of sulfur powder is added and stirred thoroughly until it is uniform, and then an acetic acid solution with a weight of 5% of natural latex is added for acidification and coagulation; the solidified mixture is filtered through a filter to achieve solid-liquid separation, and the filtered water is returned to the circulating water pool for reuse, and the solid enters the conveyor belt. During the operation of the conveyor belt, the solid passes through a drying room with flash evaporation to remove the remaining water, and then enters the extrusion mold machine to be pressed into blocks, and then cut into sheet or granular products by a slicer or pelletizer.

[0015] After adopting the technology proposed by the present invention, according to the technical solution of the present invention, the following beneficial effects are achieved:

[0016] 1) The main sulfur content can be increased to more than 95%. The process technology is environmentally friendly and efficient, can be produced continuously, has large production capacity, low energy consumption, and is environmentally friendly and clean.

[0017] 2) After increasing the main sulfur powder content, the actual application process of customers can reduce the amount of 80% content masterbatch used in the past, thereby reducing costs.

[0018] 3) Since the rubber content is significantly lower than that of previous products, it can effectively prevent the chemical deterioration of the product, extend the effective shelf life, and has no side effects on the rubber product processing process and product quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 The figure shows a process flow chart of sulfur pre-dispersion organic treatment according to the present invention. DETAILED DESCRIPTION

[0020] The present invention will be further described in detail below with reference to the embodiments shown in the accompanying drawings. The described embodiments include various specific details to aid understanding, but these should be considered as illustrative only and constitute only a portion of the present invention, not all of it. Furthermore, for the sake of clarity and brevity, detailed descriptions of functions and structures well known in the art will be omitted.

[0021] Unless otherwise defined, technical or scientific terms used herein shall have the ordinary meanings understood by persons of ordinary skill in the art to which this invention pertains. The terms "upper," "lower," or "above," and "below" herein refer to the generally defined up-and-down relationships illustrated in the accompanying drawings. When the placement state changes, such as when the device is flipped, the corresponding positional relationships should also be modified to understand or implement the technical solutions of this application.

[0022] like Figure 1 As shown, a method for producing a 1-ton sulfur powder latex pre-dispersion product is as follows: 100 kg of natural latex with a solids content of approximately 5% is added to a 3000-liter stirred tank. After dilution with approximately ten times the amount of pure water, a small amount of dispersant is added and stirred to form a latex. Then, 950 kg of sulfur powder is added and stirred thoroughly until uniform. A 5% acetic acid solution is then added for acidification and coagulation. The solidified suspension mixture is filtered through a filter to separate the solids from the liquid. The filtered water is returned to a circulating water tank for reuse. The solids are then conveyed to a conveyor belt. During operation, the conveyor belt passes through a flash drying room to remove excess moisture. The solids are then pressed into a specific size by an extrusion die machine and cut into slices or granules by a slicer or pelletizer. The dispersant preferably accounts for 5‰ of the weight of the natural latex. Unless otherwise specified in this application, all proportions are by weight at the time of use. The method for producing a 1-ton sulfur powder latex pre-dispersion product is provided as an example; in actual production, certain errors may occur depending on the process control conditions.

[0023] According to the sulfur pre-dispersion organic treatment process of the present invention, full consideration is given to the fact that the final product of the sulfur pre-dispersion is applied to rubber products. Therefore, natural latex is selected as a carrier. Natural latex is a naturally formed organic substance. The sulfur powder pre-dispersion made with it as a carrier will not have any side effects on the rubber products when applied to the rubber products.

[0024] The present invention mainly realizes the pre-dispersion treatment of sulfur by stirring and dispersing latex and sulfur and coagulating natural latex to wrap sulfur. Compared with the previous method of dissolving and dispersing rubber additives in synthetic rubber carriers such as styrene-butadiene and ethylene propylene diene monomer through mixing and other means, no chemical reaction will occur to cause failure.

[0025] According to the sulfur pre-dispersion organic treatment process of the present invention, about ten times of pure water is added for dilution. This is mainly because natural latex is viscous and not being diluted is not conducive to mixing and stirring with sulfur powder in the next step. Ten times of dilution can meet the process viscosity requirements and facilitate efficient stirring.

[0026] Latex dispersants are sodium polycarboxylate salts, which mainly reduce the viscosity of natural latex.

[0027] Adding acetic acid breaks down the molecular chains of natural latex, reducing its molecular weight and causing it to coagulate. This reaction only requires a trace amount of acetic acid, so a low-concentration acetic acid solution is preferred. Acetic acid is inexpensive, readily available, and non-toxic. It is also volatile, ensuring that any excess acetic acid is expelled.

[0028] The solid obtained after the solid-liquid separation is an amorphous solid containing a certain amount of water. However, the water content of the final product must be less than 1%, so the water is removed by flash evaporation to meet the product quality requirements.

[0029] The sulfur pre-dispersion organic treatment process according to the present invention can avoid the explosion risk caused by dust leakage when customers directly use sulfur powder.

[0030] The sulfur pre-dispersion organic treatment process disclosed herein can increase the main sulfur content to over 95%. This process is environmentally friendly, efficient, and capable of continuous production, with high production capacity, low energy consumption, and a clean, environmentally friendly design. This increased main sulfur powder content allows for a reduced usage amount in actual customer applications compared to the 80% masterbatch content previously used, reducing costs. This significantly lower rubber content effectively prevents chemical deterioration of the product, extending its shelf life without adversely affecting the rubber product processing or product quality.

Claims

1. A sulfur pre-dispersion organic treatment process, characterized in that: The natural latex liquid is added into a stirring kettle, and then ten times the weight of pure water is added to dilute it, and then a dispersant is added and stirred evenly to form a latex liquid; sulfur powder is then added and stirred thoroughly until it is uniform, and then an acetic acid solution is added for acidification and coagulation; the mixture obtained after acidification and coagulation is filtered through a filter to perform solid-liquid separation, and the solid obtained after the solid-liquid separation is subjected to a drying step to remove moisture, thereby obtaining a sulfur powder latex pre-dispersion product.

2. A sulfur pre-dispersion organic treatment process according to claim 1, characterized in that, The dispersant is a sodium polycarboxylate dispersant.

3. A sulfur pre-dispersion organic treatment process according to claim 1, characterized in that, The weight of the dispersant is 5‰ of the weight of the natural latex.

4. A sulfur pre-dispersion organic treatment process according to claim 1, characterized in that, The solid obtained after the solid-liquid separation is subjected to a drying step to remove moisture until the moisture content is less than 1%.

5. A sulfur pre-dispersion organic treatment process according to claim 1, characterized in that, The solid obtained after the solid-liquid separation enters the conveyor belt, and during the operation of the conveyor belt, it passes through a drying room with flash evaporation to remove the remaining moisture.

6. A sulfur pre-dispersion organic treatment process according to claim 1, characterized in that, The solid obtained after the solid-liquid separation is subjected to a drying step to remove moisture, and then pressed into a block by extrusion molding, and then cut into sheet or granular products by a slicer or granulator.

7. A sulfur pre-dispersion organic treatment process according to claim 1, characterized in that: The natural latex liquid is a natural latex liquid with a solid content of 5%.

8. A sulfur pre-dispersion organic treatment process according to claim 1, characterized in that: The adding of acetic acid solution for acidification and coagulation is to add acetic acid solution with a weight percentage of 5% of natural latex.

9. A sulfur pre-dispersion organic treatment process according to claim 1, characterized in that: The water obtained after the solid-liquid separation is returned to the circulating water pool for reuse.

10. A sulfur pre-dispersion organic treatment process according to claim 1, characterized in that: 100 kg of natural latex liquid with a solid content of 5% is added to a 3000L stirring kettle, and then 1000 kg of pure water is added to dilute it, and then a dispersant with a weight of 5‰ of natural latex is added and stirred evenly to form a latex liquid; then 950 kg of sulfur powder is added and stirred thoroughly until it is uniform, and then an acetic acid solution with a weight of 5% of natural latex is added for acidification and coagulation; the solidified mixture is filtered through a filter to achieve solid-liquid separation, and the filtered water is returned to the circulating water pool for reuse. The solid enters the conveyor belt, and during the operation of the conveyor belt, it passes through a drying room with flash evaporation to remove the remaining water, and then enters the extrusion mold machine to be pressed into blocks, and then cut into sheet or granular products by a slicer or pelletizer.

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