Как очистить графитовый тигель?

Graphite crucible is widely used in metallurgy, chemical industry and other fields because of its high temperature and corrosion resistance. However, it is easy to stain during use, which affects the performance and product quality. Therefore, it is very important to master the correct cleaning method of графитовый тигель.

Preparing for Cleaning Graphite Crucible

Preparing tools and materials

Brush: Prepare copper wire brush and nylon brush. You can use copper wire brush to initially clean stubborn large stains, avoid excessive damage to the crucible when using. Nylon brush texture is soft, you can use it for subsequent fine cleaning, to prevent scratching the crucible wall.

Cleaning agent: Select special graphite crucible cleaning agent, or dilute dilute hydrochloric acid solution according to the actual situation. The former is designed for graphite crucible stains and has good cleaning effect. The latter has strong dissolving power to metal oxide stains.

Soak container: Prepare a plastic container of appropriate size to ensure that the graphite crucible can be completely soaked. And its material does not react with the cleaning agent to ensure that the cleaning process is not disturbed.

Flushing equipment: Ensure that there is sufficient water, equipped with water pipes or watering cans. You can use the water hose for quick rinsing of most cleaners and stains. And the watering can is convenient for rinsing hard-to-reach corners.

Drying equipment: You can use ovens or clean towels. The oven can accurately control the temperature to achieve fast and uniform drying. The towel dries the surface of the crucible first to facilitate subsequent drying.

Safety Precautions

Wear protective gloves: Wear acid – and alkali-resistant rubber gloves to prevent the detergent from corroding the skin.

Wear goggles: There may be liquid splashing when scrubbing or rinsing. To prevent detergent from splashing into your eyes, you must wear goggles.

Ensure ventilation: Cleaning agents may volatilate irritating odor, cleaning work should be carried out in a well-ventilated environment. Timely discharge of harmful gases, to avoid operators to inhale too much harmful gases, causing dizziness, nausea and other discomfort.

Detailed cleaning graphite crucible procedures

Preliminary cleaning

Remove large debris: Use copper wire brush along the crucible texture, moderate force to scrub the surface of large metal oxides, carbon deposits, etc. In case of large metal clumps, inclined copper wire brush using toughness scraping.

Clean up internal debris: Use a long-handled copper wire brush or special tools to carefully go deep into the bottom and corner of the crucible. To clean up accumulated debris and avoid collision with the inner wall.

Soaking session

Mix detergent solution: Mix in plastic container according to detergent instructions. If using dilute hydrochloric acid, mix it with water at 1:10 or 1:15 to ensure that the concentration is appropriate.

Fully soak the crucible: Place the initially cleaned crucible slowly to ensure immersion. Generally soak 2-4 hours, the stain can be extended seriously. So that the detergent reacts with the stain and softens the stain.

Deep cleaning

Clean with nylon brush: Remove after soaking and gently brush the inside and outside of the crucible with nylon brush. For stubborn stains, dip a small amount of detergent solution and scrub vigorously.

Wipe the detailed parts: With a rag or cotton swab dipped in detergent, carefully wipe the edge of the crucible, corners and other difficult parts to brush. To ensure that there is no stain residue.

Rinse and dry

Clean water rinse: Use water pipe or watering can, wash from the top to the top with large water flow. Check all parts to ensure that there is no cleaning residue, pay attention to the crevices.

Wipe off surface moisture: Gently dry most of the moisture with a clean towel to prevent impurities from scratching the crucible.

Drying treatment: Put the crucible into the oven and bake at 80-100 °C for 1-2 hours, and observe regularly during the time to ensure thorough drying. After drying, put it in a dry and clean place for use.

Cleaning points for different types of stains

Metal oxide stains

Chemical dissolution principle: The use of acid and metal oxide reaction to produce soluble salt and water to remove pollution. For example, dilute hydrochloric acid reacts with iron oxide, Fe2O3 + 6HCl = 2FeCl3+ 3H2O.

Cleaning precautions: Strictly control the concentration and soaking time of dilute hydrochloric acid and other acidic cleaners to prevent corrosion of graphite crucible. Be sure to rinse thoroughly after cleaning to avoid detergent residue affecting the subsequent use of the crucible.

Carbon stains

Mechanical and chemical combination: First remove most of the carbon deposit through preliminary mechanical scrubbing. And then let the detergent penetrate into the carbon deposit interior for decomposition with the help of immersion. And thoroughly remove it with a nylon brush during deep cleaning.

Use of special cleaning agents: For stubborn carbon accumulation, special cleaning agents containing strong oxidizing components can be used to oxidize and decompose carbon accumulation. However, you should pay attention to controlling the detergent concentration and use time to prevent damage to the crucible.

Меры предосторожности

Avoid damaging the crucible

Control brushing strength: When using copper wire brush and nylon brush to clean, strictly control the strength. Preliminary cleaning with copper wire brush to remove stubborn stains, also can not be too hard. To prevent scratching the surface of the crucible, affecting the service life.

Prevent collision: Move and clean the graphite crucible carefully to avoid collision with hard objects. As in or out of the immersion container gently handle gently, otherwise the collision is easy to crack or damage the crucible.

Detergent selection

Ensure compatibility: Choose the cleaner suitable for the graphite crucible material. Different stains correspond to different types, such as acidic cleaners for metal oxides, special cleaners for carbon deposits. To prevent the reaction with graphite to damage the crucible.

Pay attention to environmental protection and safety: Give priority to environmental protection and low toxic cleaning agents to reduce environmental pollution and harm to human health. Read the instructions carefully before use to understand the ingredients, usage and precautions.

Drying temperature control

Control temperature range: The temperature of the dry graphite crucible should be 80-100°C. The temperature is too high, such as over 150°Cmay change its internal structure and reduce thermal stability.

Prevent sudden temperature change: Avoid sudden cooling of the crucible when drying, after high temperature drying can not be immediately put into the cold air. You should cool it in the oven to close to room temperature and then remove it. To prevent thermal expansion and contraction cracks.

Заключение

Correct cleaning of graphite crucible is of great significance to ensure performance and prolong life. Do the preparatory work, follow the steps, choose the right method for different stains, pay attention to various precautions, you can effectively and safely clean.