Concentrate processing manufacturing process

One universal type of concentrate was manufactured in Pug Mills of the type typically used to mix clay in the pottery industry. No one manufacturing method works for all polymers and generally the more versatile the process the less optimized it is for any one product. 

On the other hand, in terms of manufacturing processes, the procedures employed will have to be improved continually, to improve the efficiency of the cation-exchange procedure, to manufacture silica sols continuously, and to enhance the efficiency of the concentration processes. 

Once the reaction is complete, the reaction mixture is passed over a suitable separator such as a vacuum belt filter, rotary filter, filter press, or decanter to separate crystals from the mother liquor and washed free of excess reactants (see Figure 22.12). The hot deionized wash water may be evaporator condensate, which is recycled from the mother liquor concentration process. Volumes and, therefore, evaporation costs can be minimized by using a countercurrent washing process. The effluent wash water has a pH value between 9 and 12. The mother liquor filtrate and wash water contain excess of sodium hydroxide and possibly an excess of alumina. The complete utilization of the mother liquor is essential in the manufacturing of zeolites. Therefore, it is concentrated in... 

Figure 2.12. Original and processed images of some real experimental CLs with different pore promoter additive concentrations during manufacture.

Schweizer s reagent The dark blue solution obtained by dissolving Cu(OH)2 in concentrated ammonia solution. Used as a solvent for cellulose, the cellulose is precipitated on acidification. Used in the cuprammonium process for the manufacture of rayon. 

Industrially. phosphoric(V) acid is manufactured by two processes. In one process phosphorus is burned in air and the phos-phorus(V) oxide produced is dissolved in water. It is also manufactured by the action of dilute sulphuric acid on bone-ash or phosphorite, i.e. calcium tetraoxophosphate(V). Ca3(P04)2 the insoluble calcium sulphate is filtered off and the remaining solution concentrated. In this reaction, the calcium phosphate may be treated to convert it to the more soluble dihydrogenphosphatc. CafHjPOjj. When mixed with the calcium sulphate this is used as a fertiliser under the name "superphosphate . 

Demand for Caustic Soda Types. Approximately 99% of the sodium hydroxide produced in 1987 was 50% caustic solution (5). Higher concentrations require additional evaporation and therefore increased prices relative to the sodium oxide values. To obtain maximum value, users have learned to adapt manufacturing processes to the 50% caustic soda. 

Manufacture of Fatty Acids and Derivatives. Splitting of fats to produce fatty acids and glycerol (a valuable coproduct) has been practiced since before the 1890s. In early processes, concentrated alkaU reacted with fats to produce soaps followed by acidulation to produce the fatty acids. Acid-catalyzed hydrolysis, mostly with sulfuric and sulfonic acids, was also practiced. Pressurized equipment was introduced to accelerate the rate of the process, and finally continuous processes were developed to maximize completeness of the reaction (105). Lipolytic enzymes maybe utilized to spHt... 

Newer coal-based methods of acetylene manufacture under development include the AVCO process, based on the reaction of coal in a hydrogen plasma. Finely divided coal is passed through a hydrogen plasma arc generating temperature gradients of up to 15,000 K. About 67% of the coal is consumed, yielding char and acetylene in concentrations up to 16%. An energy requirement of 9.5 kW h/kg acetylene has been reported (33). 

The U.S. domestic commercial potassium nitrate of the 1990s contains 13.9% N, 44.1% I+O, 0—1.8% Cl, 0.1% acid insoluble, and 0.08% moisture. The material is manufactured by Vicksburg Chemical Co. using a process developed by Southwest Potash Division of AMAX Corp. This process uses highly concentrated nitric acid to catalyze the oxidation of by-product nitrosyl chloride and hydrogen chloride to the mote valuable chlorine (68). The much simplified overall reaction is... 

Water is continuously added to the last extraction bath and flows countercurrenfly to filament travel from bath to bath. Maximum solvent concentration of 15—30% is reached in the coagulation bath and maintained constant by continuously removing the solvent—water mixture for solvent recovery. Spinning solvent is generally recovered by a two-stage process in which the excess water is initially removed by distillation followed by transfer of cmde solvent to a second column where it is distilled and transferred for reuse in polymer manufacture. 

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