Aluminum sulfate solid is a white crystal, which is widely used in various industries as an industrial agent. Use of aluminum sulfate In the paper industry, paper is composed of fibers (wood pulp or straw pulp). Unsized paper has water absorption and is not suitable for writing and printing. In addition, the strength of the paper will also decrease after absorbing water, thereby affecting its use. Therefore, except for special paper such as toilet paper, filter paper, and cigarette paper, about 80% of the paper needs to be added to the pulp or coated with some water resistant substances on the surface of the paper, so that the paper has the performance of delaying fluid penetration to achieve ink resistance and oil resistance (such as food packaging paper). This aluminum sulfate technology process is called sizing, and the added substances are called aluminum sulfate sizing agents. Based on the analysis of the sizing principle of aluminum sulfate sizing agents, it is necessary to have both hydrophilic and hydrophobic groups in the sizing agent molecules, so that they can be uniformly retained on the fiber surface by themselves or with the aid of other retention aids, allowing the hydrophilic group to combine with the fiber, and the hydrophobic group to turn to the outside of the fiber to reduce the surface free energy between the fiber and air, change the contact angle of the liquid on the fiber surface, and achieve the purpose of sizing. Most papers require sizing. Aluminum sulfate sizing agents can also be subdivided into intra pulp sizing agents and surface sizing agents. Intrapulp sizing agents are a widely used chemical with a large amount in the paper industry, as aluminum sulfate is mainly used for intra pulp sizing in papermaking. Aluminum sulfate is mainly used as a sizing agent for papermaking and a flocculant for drinking water, industrial water, and wastewater treatment. It is also used as a raw material for the production of artificial gemstones and other aluminum salts, ammonia alum, potassium alum, and refined aluminum sulfate. In addition, it is widely used as high-quality clarifying agent, petroleum deodorant and decolorizing agent, concrete waterproof agent and waterproof cloth raw material, high-grade paper forging and whitening, titanium dioxide post film treatment, and catalyst carrier production.