The Manufacture of Paper

Mechanical pulp mills are normally on the same site and integrated with paper production, e.g. of newsprint. Chemical pulp mills can be integrated or sell market pulp that is flash dried and baled. Here, the capillary tension on drying pulls baek the loose fibrillated wall elements to re-bond to the external surface of the fibre, and 

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Fumaric acid and malic acid [6915-15-7] are produced from maleic anhydride. The primary use for fumaric acid is in the manufacture of paper siting products (see Papermaking additives). Fumaric acid is also used to acidify food as is malic acid. Malic acid is a particularly desirable acidulant in certain beverage selections, specifically those sweetened with the artificial sweetener aspartame [22839-47-0]. 

The principle uses of Na2S04 are in the manufacture of paper, soaps, and detergents. These accounted for 65% of U.S. consumption from 1990 to 1995, representing a significant shift from 1980 when paper production alone consumed 67%. Pulp (qv) and paper consume only 25% (2). The kraft paper process uses a mixture of sodium sulfide and sodium hydroxide to digest wood chips. Both the sulfide and hydroxide are generated, starting with sodium sulfate as the raw material. 

The cellulose fiber in paper is attacked and weakened by sulfur dioxide. Paper made before about 1750 is not significantly affected by sulfur dioxide (11). At about that time, the manufacture of paper changed to a chemical treatment process that broke down the wood fiber more rapidly. It is thought that this process introduces trace quantities of metals, which catalyze the conversion of sulfur dioxide to sulfuric add. Sulfuric acid causes the paper to become brittle and more subject to cracking and tearing. New papers have become available to minimize the interaction with SO2. 

Among the basic fields of applications, the major use of acrylamide polymers is liquid-solid separation in water treatment and waste treatment. Smaller quantities are used in the manufacturing of paper and in the processing of minerals in mining. Relatively nonlarge quantities are use as additives for enhanced oil recovery. 

C03-0152. Aluminum sulfate is used in the manufacture of paper and in the water purification industry. In the solid state, aluminum sulfate is a hydrate. The formula is AI2 (804)3 18 H2 O. (a) How many grams of sulfiar are there in 0.570 moles of solid aluminum sulfate (b) How many water molecules are there in a 5.1-g sample of solid aluminum sulfate (c) How many moles of sulfate ions are there in a sample of solid aluminum sulfate that contains 12.5 moles of oxygen atoms (d) An aqueous solution of aluminum sulfate contains 1.25% by mass aluminum and has a density of 1.05 g/mL. What is the molarity of aluminum ions in the solution ... 

Pulping liquors. Pulping liquor, also called black liquor, is a corrosive material used to dissolve wood chips for the manufacturing of paper and other materials. To promote waste minimization and recycling, U.S. EPA excluded pulping liquors from the definition of solid waste if they are reclaimed in a recovery furnace and then reused in the pulping process. If the liquors are recycled in another way, or are accumulated speculatively, they are not excluded. 

Processes in the manufacture of paper and paperboard can, in general terms, be divided into three steps ... 

An organic material which occurs in the woody tissues of plants. It is a by-product in the preparation of cellulose for the manufacture of paper, rayon and the cellulose plastics, and its use has been proposed as a reinforcing filler for rubber. 

Used industrially for dehairing hides, wool pulling, ore flotation, metal refining, engraving, cotton printing, in the manufacture of paper, pharmaceuticals, rubber, and sulfur dyes. It is used in production of heavy water for nuclear reactors. 

Refined borax (Na B Op is an additive in laundry products such as soaps and water-softening compounds. Also used for cosmetics, body powders, and the manufacture of paper and leather. Borax is an environmentally safe natural herbicide and insecticide. 

Less chemistry is involved in the manufacture of paper once the pulp has been made, but it is a complex process that can be summarized in the following steps ... 

There are many chemicals that are important in the manufacture of paper. These paper additives include pigments and dyes, wet-strength resins, sizes. 

Calcium hydroxide has wide industrial applications. It is used to make cement, mortar, plaster, and other building materials. It also is used in water soluble paints, and for fireproofing coatings and lubricants. Other applications are in the manufacture of paper pulp as a preservative for egg in vulcanization of rubber as a depilatory for hides and in preparation of many calcium salts. 

In the manufacture of paper, starch-based adhesives are used either to strengthen the paper base or for coating the surface of the paper. Raw starch is unsuitable for either purpose. To achieve sufficient adhesive power with raw starch would require the application of a solution that was far too thick for practical use. Instead, chemically modified starch, with a much lower viscosity in solution, is used. As an economical alternative to modifying the starch with aggressive oxidizing agents, the starch can be treated with enzymes ( df-amylases) to obtain the same thinning effect... 

The Food and Dmg Administration (1999) permits the use of di(2-ethylhexyl) phthalate in the United States as a component of adhesives used in food packaging, as a plasticizer in resinous and polymeric coatings used in food packaging, as a component of defoaming agents used in the manufacture of paper and paperboard used in food packaging, as a flow promoter in food contact surfaces not to exceed 3 wt% based on monomers, as a component of cellophane where total phthalates do... 

The Food and Drug Administration permits the use of diethanolamine as a component of adhesives in food packaging, as an indirect food additive, as a component of the uncoated or coated food contact surface of paper and paperboard for use with dry solid foods with no free fat or oil on the surface, and for use only as an adjuvant to control pulp absorbance and pitch content in the manufacture of paper and paperboard or for use only in paper mill boilers in the United States (Food and Drug Administration, 1999). 

Description Sulfur dioxide (S02) is a gas resulting from the combustion of coal, mainly in power plants, and certain types of liquid fuels that contain sulfur. In addition, it is produced during the manufacture of paper and smelting of metals. It may cause respiratory problems and permanent damage to the lungs when inhaled at high levels. It plays a major role in the production of acid rain (EPA site). Carbon disulfide (CS2) has many industrial... 

C. Chlorophenols. Chlorophenols have been extensively used since the 1930 s as insecticides, fungicides, mould inhibitors, antiseptics and disinfectants. The annual production volume is estimated to be in the order of 150 000 tons. In the US penta-chlorophenol is the second heaviest in use of all pesticides (38). The most important use of 2,U,6-tri, 2,3,, 6-tetra- and pentachlorophenol (or their salts) is for wood protection. Penta-chlorophenol is also used as a fungicide for slime control in the manufacture of paper pulp and for a variety of other purposes such as in the tanning process of leather and an additive in cutting oils and fluids, paint, glues and out-door textiles. 

As prussian blue, when once dried, is difficult to reduce again to the state of extreme division which it possessed in the moist state, it is often sold and employed in paste—that is to say, not dried—especially for the manufacture of paper-hangings, et cetera. 

Tall oil is a byproduct obtained from the manufacture of paper pulp from pine trees. It is separated by vacuum distillation (50 mm Hg) in the presence of steam into four primary products. In the order of decreasing volatility these are unsaponifiables (US), fatty acid (FA), rosin acids (RA), and pitch (P). Heat exchangers and rcboilers are heated with Dowtherm condensing vapors. Some coolers operate with water and others generate steam. Live steam is charged to the inlet of every reboiler along with the process material. Trays are numbered from the bottom of each tower. 

The hollow fibers still contain an acid solution within them. In order that this acid may be washed out, they are pulped or broken up into short lengths by means of apparatus like that which is used in the manufacture of paper. A Jordan mill cuts the fibers off rather sharply, leaving square ends, but a beater tears... 

Examination of the practical applications of ion radicals includes coverage of their roles in biological systems as well as in material chemistry, ranging from optoelectronics, organic metals, and magnets to lubricants and the manufacture of paper. 

FDA. 1999e. U.S. Food and Dmg Administration. Code of Federal Regulations. 21 CFR 176.210 Defoaming agents used in the manufacture of paper and paper-board. 

Sodium hydroxide has many different uses in the chemical industry. Considerable amounts are used in the manufacture of paper and to make sodium hypochlorite for use in disinfectants and bleaches. Chlorine is also used to produce vinyl chloride, the starting material for the manufacture of polyvinyl chloride (PVC), and in water purification. Hydrochloric acid may be prepared by the direct reaction of chlorine and hydrogen gas or by the reaction of sodium chloride and sulfuric acid. It is used as a chlorinating agent for metals and organic compounds. 

The shortage of oil and natural gas has been reflected in shortages and spiraling prices for polymers based on petrochemical resources. Providentially, such polymers may be in part replaced by lignocellulosic materials that are the most abundant and most economical organic renewable resources available. In their natural state as wood and plant fibers, and as the principal constituent used in the manufacture of paper, textile fibers, and many other industrial products, lignocellulosic materials will continue to be fundamental to human welfare. 

Used in the manufacture of paper and soap, in oil refining, and other industries... 

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