Solid caustic, production

Chemical Reactivity - Reactivity with Water A slow, non-hazardous reaction occurs, forming propanolamine Reactivity with Common Materials No reactions Stability During Transport The product is stable if it is kept in contact with solid caustic soda (sodium hydroxide) Neutralizing Agents for Acids and Caustics Dilute with water and rinse with vinegar solution Polymerization This material will polymerize explosively when in contact with any acid Inhibitor of Potymerization Solid sodium hydroxide (caustic soda). 

Methylated spirit contains, in addition to ethyl and methyl alcohols, water, fusel-oil, acetaldehyde, and acetone. It may be freed from aldehyde by boiling with a—3 per cent, solid caustic potash on the water-bath with an upright condenser for one hour, or if larger quantities are employed, a tin bottle is preferable, which is heated directly over a small flame (see Fig. 38). It is then distilled with the apparatus shown in Fig. 39. The bottle is here surmounted with a T-piece holding a thermometer. The distillation is stopped when most of the spirit has distilled and the thermometer indicates 80°. A further purification may be effected by adding a little powdered permanganate of potash and by a second distillation, but this is rarely necessary. The same method of purification may be applied to over-proof spirit, which will henceforth be called spirit as distinguished from the purified product or absolute alcohol. 

Dichloroethylene in contact with solid caustic alkalies or their cone, solutions will form chloroacetylene which ignites in air [1], Distillation of ethanol containing 0.25% of the halocarbon with aqueous sodium hydroxide gave a product which ignited in air [2]. 

First, the tar acids were removed from the naphtha fractions of light oils and, in the case of CVR tars, carbolic oil. The oils were then mixed with 25—35% sulfuric acid. After separation of the sulfates, the aqueous solution was diluted with water and the resinous material skimmed off. The diluted sulfate solution was boiled to expel any neutral oils, dried by the addition of solid caustic soda or azeotropically with benzene, and fractionated to yield pyridine, 2-methylpyridine (a-picoline), and a fraction referred to as 90/140 bases, which consisted mainly of 3- and 4-methylpyridines and 2,6-dimethylpyridine (2,6-lutidine). Higher boiling fractions were termed 90/160 and 90/180 bases because 90% of the product distilled at 160 and 180°C, respectively. 

A schematic drawing is shown in Figure 2. The small amounts of ester formed are reverted with a caustic-treating plus water wash. Distillation in a light ends column removes unreacted olefins, paraffin byproduct, plus other light components present in the crude alcohol. A second distillation is used to remove trace heavy components. Hydrogenation eliminates trace unsaturation, aldehydes, etc. Filtration assures clear, solids free product. 

It was the practice to neutralize slight acidity in such solvents in a pressure vessel (called a neutralizer) that was filled with solid caustic soda flakes or beads. Such treatment was a common method to improve tainted inventories of solvent intermediates and products. The operating team was pleased to secure the equipment and caustic soda to improve this product. 

The product of dais reaction can be removed as an azeotrope (84.1% amide, 15.9% acetic acid) which boils at 170.8—170.9°C. Acid present in the azeotrope can be removed by the addition of solid caustic soda [1310-73-2] followed by distillation (2). The reaction can also take place in a solution having a DMAC-acetic acid ratio higher than the azeotropic composition, so that an azeotrope does not form For dais purpose, dimethylamine is added in excess of the stoichiometric proportion (3). If a substantial excess of dimethylanoine reacts with acetic acid under conditions of elevated temperature and pressure, a reduced amount of azeotrope is formed Optimum temperatures are between 250 —325°C, and pressures in excess of 6200 kPa (900 psi) are required (4). DAIAC can also be made by the reaction of acetic anhydride [108-24-7] and dimethylamine ... 

In 50 g/1 solid caustic yields a product that has very good detergency, low foam, and a wetting time (via Draves Cotton Skew Test) of agent 10-13 seconds. 

Allows hardness to break through ion-exchange beds and attack membranes damage to evaporators and contamination of caustic product Equipment damage deactivation of anode coating Lower-quality product accumulation in compressor suction duller, higher bromaie concentration in bleach Accumulation of very finely divided solids in membrane s... 

Solid caustic itself is not corrosive and it, too, is handled and stored in carbon steel equipment. It is very hygroscopic, however. Its corrosivity and the flow properties of the commercial forms are sensitive to moisture. Packages are lined and carefully sealed to prevent corrosion and product degradation. 

Solid Forms and Their Production. There is a relatively small market for solid caustic. Certain applications require the fused material, and in other cases freight savings offset the additional processing cost. We consider three forms of solid here bulk, flaked, and prilled. KOH is seldom formed into prills. 

The purpose of chemical protective clothing is to protect the wearer against the effect of toxic or corrosive/caustic products which could enter the body (inhalation, skin absorption) or cause tissue damage upon contact with the skin. These products could be in vapor, liquid, or solid form. One type of material is not compatible with every type of chemical. While it may provide excellent resistance against one chemical, the same material may provide very poor or no protection against another chentical. The levels of protection under OSHA standards are as follows ... 

Production of solid caustic soda. Usually, the electrolysis plants are producing a 50% NaOH solution. Solid, 100% NaOH is obtained by evaporating tbe solution until the water content is below 0.5 to 1.5 wt%. 

Between 42 and 50% of the production is used in the chemical industry. Most customers require dilute aqueous solutions, the application of waterffee solid caustic soda is limited to drying processes, waterfree organic reactions, and to exports into countries with logistic problems in handling greater amounts of liquid solutions the share is only 2 - 3 % of the production. 

Further SO2 removal is carried out by contacting the S02-bearing tail gas with a basic solution that removes SO2 forming a liquid or solid by-product or waste (Fig. 28.2). The basic solution is often caustic NaOH(aq) (caustic) or Ca(OH)2(aq) (lime). 

The company is authorized to engage in foreign trade and exports over US 30 million worth of chemical products each year. It has a joint venture with Bayer to produce polycarbonate with annual capacity of 18 000 tonnes. Major products of the company include liquid caustic soda, solid caustic soda, diaphragm caustic soda, PVC resin, liquid chlorine, muriatic (hydrochloric) acid, chlorinated paraffin, chlorinated rubber, trichloro hydrogen-silicon, sodium hypochlorite, carbon tetrachloride, perchloroethylene, calcium hypochlorite, hydrogen fluoride acid, tetrafluoro-dibromoethane, polytetrafluoroethylene (PTFE) resin, and fluorine refrigerant. 

They are best prepared by adding the amine gi adually and ith cooling to ti ong aqueous fomialdehyde (approximately 37 per cent). The reaction mixtui e ia then treated Adth caustic alkali, which cau-ses the product to separate as an upper phase. The substituted methyleneamines are readily pmified by distillation o el solid caustic. If desired, the reaction mixture may be extracted with ether. This is of particular value in the ca.se of the lower derivatives, which are the more soluble in water. 

The residue in the flask will contain the sodium (or potassium) salt of the acid together with excess of alkali. Just acidify with dilute sulphuric acid and observe whether a crystalline acid separates if it does, filter, recrystallise and identify (Section 111,85). If no crystaUine solid is obtained, the solution may be just neutralised to phenolphthalein and the solution of the alkali salt used for the preparation of a crystaUine derivative. This wiU confirm, if necessary, the results of hydrolysis by method 1. If the time factor is important, either method 1 or the product of the caustic alkali hydrolysis may be used for the identification of the acid. 

Oxidation or "sweetening" is used on gasoline and distillate fractions. A common oxidation process is also a Merox process that uses a solid catalyst bed. Air and a minimum amount of alkaline caustic ("mini-alky" operation) is injected into the hydrocarbon stream. As the hydrocarbon passes through the Merox catalyst bed, sulfur mercaptans are oxidized to disulfide. In the sweetening Merox process, the caustic is not regenerated. The disulfide can remain with the gasoline product, since it does not possess the objectionable odor properties of mercaptans hence, the product has been sweetened. 

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