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Paper chemicals designate a group of chemicals that are used for paper manufacturing, or modify the properties of paper. These chemicals can be used to alter the paper in many ways, including changing its color and brightness , or by increasing its strength and resistance to water. [ 1 ]
Paper made from chemical pulps are also known as wood-free papers (not to be confused with tree-free paper); this is because they do not contain lignin, which deteriorates over time. The pulp can also be bleached to produce white paper, but this consumes 5% of the fibres.
Shqip; Simple English; ... Pages in category "Chemical processes" The following 200 pages are in this category, out of approximately 255 total. ... Paper chemicals ...
It enabled the recovery and reuse of the inorganic pulping chemicals such that a kraft mill is a nearly closed-cycle process with respect to inorganic chemicals, apart from those used in the bleaching process. For this reason, in the 1940s, the kraft process superseded the sulfite process as the dominant method for producing wood pulp. [6]
Chemical pulp is produced by combining wood chips and chemicals in large vessels called digesters. There, heat and chemicals break down lignin, which binds cellulose fibres together, without seriously degrading the cellulose fibres. Chemical pulp is used for materials that need to be stronger or combined with mechanical pulps to give a product ...
Handmade paper is also prepared in laboratories to study papermaking and in paper mills to check the quality of the production process. The "handsheets" made according to TAPPI Standard T 205 [ 20 ] are circular sheets 15.9 cm (6.25 in) in diameter and are tested for paper characteristics such as brightness, strength and degree of sizing . [ 21 ]
Today, the field of paper and chemical engineering is applied to the manufacture of a wide variety of products. The forestry and biology, chemical science, (bio)chemical industry scope manufactures organic and agrochemicals (fertilizers, insecticides, herbicides), oleochemicals, fragrances and flavors, food, feed, pharmaceuticals, nutraceuticals, chemicals, polymers and power from biological ...
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