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Resin removal from pulp

Table XVII is an example of the test result showing comparable efficiency of SAE, PAE and alkylphenol ethoxylates in resin removal from sulfite pulp. A Japanese patent specification(24) by Lion Fats and Oils describes 10-16 mole ethoxylates of secondary alcohols as extremely useful in deresination of pulp, especially in the manufacture of dissolved pulp for the rayon industry. According to the patent specification, to alkyls give the best results among 12 mole ethoxylates ethoxylates of from 10 to 13 moles of EO can give the best results among other ethoxylates of C secondary alcohols, and the optimum amount of SAE(12E0) is in the range between 0.2 and 0.6% by weight based on pulp. Table XVII is an example of the test result showing comparable efficiency of SAE, PAE and alkylphenol ethoxylates in resin removal from sulfite pulp. A Japanese patent specification(24) by Lion Fats and Oils describes 10-16 mole ethoxylates of secondary alcohols as extremely useful in deresination of pulp, especially in the manufacture of dissolved pulp for the rayon industry. According to the patent specification, to alkyls give the best results among 12 mole ethoxylates ethoxylates of from 10 to 13 moles of EO can give the best results among other ethoxylates of C secondary alcohols, and the optimum amount of SAE(12E0) is in the range between 0.2 and 0.6% by weight based on pulp.
In the past, when softwoods were the source of most pulpwood, the major problems caused by extractives were those of pitch, largely resulting from the resin and fatty acids and unsaponifiable materials. Next came the problems caused by the discoloration of pulp due to the presence of polyphenols in hardwoods, notably eucalypts. Now with the increasing use of relatively unfamiliar tropical hardwoods, some of which contain large amounts of extractives, new problems are arising due to polyphenols and a group of resins different from those previously encountered. Differences in their behavior include difficulties in their removal by bleaching and in their removal from pulp mill equipment (e.g., 99). New methods need to be devised to minimize their influence and overcome these difficulties. [Pg.881]

Phenol and its compounds are ubiquitous water pollutants that are present in the effluents of a variety of chemical industries such as coal refineries, phenol manufacturing, pharmaceuticals, and industries of resin, paint, dyeing, textile, leather, petrochemical, pulp mill, etc. [9]. Phenols are known to be toxic and also, some of them, hazardous carcinogenic that can accumulate in the food chain. Phenolic compounds are a public health risk and they are heavily regulated in many countries, and must be removed from wastewater before they are discharged into the environment [10], For example, a 10 days consumption of polluted water with low concentrations (3 ppm) of 2,4-dichlorophenol can cause vomiting, paralysis, and even death in children [11, 12]. Phenol, 2-chlorophenol, and 2,4-dichlorophenol are ranked within the 250 most hazardous pollutants [13]. In addition, chlorophenols are commonly found in chlorinated water, since phenol can react with chlorine [14],... [Pg.182]

The polyester alkyd molding compositions are also based on a polyester resin similar to those used for laminating. (The term alkyd is derived from alcohol and acid.) They are prepared by blending the resin with cellulose pulp, mineral filler, pigments, lubricants, and peroxide curing systems on hot mills to the desired flow properties. The mix is then removed, cooled, crushed, and ground. [Pg.445]

Pump molding n. A process by which a resin-impregnated pulp material is preformed by application of a vacuum and subsequently oven cured or molded. The pulp is first mixed with water and pumped into a tank wherein a mold, usually of wire mesh shaped like the finished article, is positioned. Air is evacuated from the mold to attract the pulp fibers, forming a preformed layer in contact with the screen. The mold is then removed from the vacuum tank, the pulp deposit is stripped off and dried, then, the preform is molded to final form by fluid pressure or conventional compression methods. [Pg.801]

The ionizable carboxyl groups in the resin ionize completely in alkaline solution to stabilize the pitch dispersion. However, in the neutral conditions in paper mills, the multivalent metal ions, such as calcium or magnesium, when inadequately washed from the pulp, precipitate the resin and fatty acids as soaps that are difficult to dissolve and remove. Within the normal pH range in the paper mill system, aluminum soaps are charged positively and partly stabilize the dispersion and partly enable the soap particles to be drawn to the negatively charged fiber and thus removed from the system with the paper. Care is needed with the addition of alum, which decreases the pH value and increases corrosion, lowers the strength of the paper, and affects other paper properties. Nevertheless acid conditions of pH 4.5-5.5 can considerably reduce the pitch problem encountered at pH 6-8 and, for that purpose, sulfuric acid alone has been added. [Pg.892]

The recovery of terpenes and fatty and resin acids from the kraft pulping of resinous species can improve the economy of the operations. During the pulping of Pinus spp., the gases released from the digester are condensed and the turpentine decanted from the aqueous distillate. The removal of the sodium salts of fatty and resin acids from the black liquor followed by acidification give tall oil, which is refined into a number of commercially important products. These aspects will be dealt with elsewhere in this volume (Sect. 10.1). [Pg.912]

The lignin residues from wood pulp production are another class of extractives currently receiving attention as phenolic resin additives. Substituted phenols, such as cresols and xylenols, have been used as glue mix additives for phenolic adhesive resins to improve assembly time tolerance. They are also used as solvents to remove oleo-resinous deposits on the surface of pitchy softwood veneers. They can be used as flow promoters in phenolic hardwood adhesives. To avoid interference with the rate of resin curing, the amount added should not exceed 3 to 4% of the phenolic resin solids content. [Pg.556]

For our publication in this subject [14], we focused on elucidating the structure of cellulose acetate (CA)-U02[VI), because despite the importance of using cellulose derivatives as chelating resins for removing rare metal ions in waste- and sea-water, before year of publishing of this study, there was a lack of Information regarding the structure of cellulose acetate-U02 (VI) complexes. We had prepared cellulose acetate-U02[VI] complex samples from three degrees of substitution of viscose pulp with uranyl acetate. The role of acetyl content of CA on the amount of chelated uranium was also evaluated [Table 7.6]. [Pg.272]

An American plant of this type is in operation at Moab, Utah, with a capacity of 1800 tons of ore per day. Baskets are 6 ft by 6 ft by 6 ft in size, up to nine or ten being used in series for absorption from the pulp. It has in this case been found advisable to remove all ore particles above 325-mesh size since those in the 200-325-mesh region tended to coat the resin grains, prevent access of the liquor and reduce the resin loading capacity by as much as 25 per cent. [Pg.110]


See other pages where Resin removal from pulp is mentioned: [Pg.169]    [Pg.438]    [Pg.68]    [Pg.296]    [Pg.1038]    [Pg.912]    [Pg.109]    [Pg.345]    [Pg.378]    [Pg.140]    [Pg.866]    [Pg.867]    [Pg.51]    [Pg.479]    [Pg.482]    [Pg.295]    [Pg.140]    [Pg.378]    [Pg.459]    [Pg.293]    [Pg.990]    [Pg.356]    [Pg.8]    [Pg.354]    [Pg.328]    [Pg.499]    [Pg.68]    [Pg.719]    [Pg.2085]    [Pg.115]    [Pg.1602]    [Pg.287]    [Pg.179]    [Pg.296]    [Pg.290]    [Pg.1158]   
See also in sourсe #XX -- [ Pg.86 ]




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Resins removal

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