Acids safe dilution

The choice of materials as non-examples is not so obvious since many non-acids, such as copper(II) sulfate, dissolve in water and then react with the water to make acidic solutions. These must be avoided. I recommend aqueous solutions of sodium chloride, magnesium sulfate and sodium nitrate, which will suit the purpose of acting as non-acids. The choice of acids is also not so obvious but, if magnesium ribbon is used for the reactive metal, it will react appropriately with dilute nitric acid, forming hydrogen. The mineral acids - hydrochloric, sulfuric, nitric and phosphoric acid -in dilute solution are all relatively safe for this activity with the usual... 

Sahcyhc acid USP, EP, and other pharmacopeia grades are used medically as antiseptic, disinfectant, antifungal, and keratolytic agents. Sahcyhc acid is formulated in lotion or ointment formulations for the treatment of dandmff, eczema, psoriasis, and various parasitic skin diseases. Because the keratolytic property of this aromatic acid has use in the safe removal of dead skin cells from the surface of healthy skin, the acid is used in concentrated sahcyhc acid solutions or suspensions to remove warts and corns. In more dilute form, sahcyhc acid preparations have found use in dandmff and eczema treatment. Sahcyhc acid has been considered and found effective by the Advisory Committees to the FDA in various over-the-counter (OTC) dmg regulated uses. Among these are acne products, dermatitis, dry skin, dandmff and psoriasis products, and foot care products (24). 

SpiHs can also be diluted with large volumes of water. Care should be taken, however, because chlorosulfuric acid reacts violentiy with water Hberating heat, hydrochloric acid, and sulfuric acid mists and steam. The water should be appHed from a safe distance upwind of the spiH using a fog no22le. Remaining traces of acid should be neutrali2ed with soda ash, caustic soda, or lime before disposal. 

The MCA Data Sheet covers safe handling procedures for all grades of sulfuric acid from fuming (oleum) through cone, to diluted acid. Coverage of the other... 

However, because both acids and bases are used in cleaning, it may be possible to store these chemicals in a stirred buffer tank to allow the solution to neutralise. This solution may then may be slowly added to the concentrate waste to dilute it and allow for a safe disposal (Mauguin and Corsin 2005). Note that the volume of this discharge is much lower than both the concentrate and filter backwash discharges. 

Iron and acetic or dilute hydrochloric acid can be safely used for the reduction of nitro group to an amino group in nitro esters. The problem arises when a nitro ester is to be reduced to a nitro alcohol. Nitro groups are not inert toward the best reagents for the reduction of esters to alcohols, complex hydrides. However the rate of reduction of a nitro group by lithium... 

Safe, economical, and efficient stripping nsing only water or dilute acidic solution... 

Nitro substituents and heterocyclic nitrogen influence not only the yield of fluorodediazoniation but also the rate of decomposition which, in these cases, is too high to perform the reaction on a multigram scale. Some explosions have been reported. Thus, the decomposition of nitro-substituted or heterocyclic diazonium tetrafluoroborates is usually controlled by three-to fivefold dilution of these substrates in inert solids, such as acid-washed sand,113 218 Kiesel-guhr,3 sodium carbonate,3 barium sulfate,217 sodium fluoride,216 or sodium tetrafluoroborate.3 This modified technique has been generalized to the decomposition of all kinds of diazonium tetrafluoroborates under safe conditions, even on rather large scales. 

In tills method a known copper deposit would be injected in several locations with a solution of dilute sulfuric acid, This acid would percolate through Ihe veins of the ore-bearing rock (usually copper oxidel. The copper would go into solution as copper sulfide and be pumped to the surface by way of several recovery wells. At the surface the copper would be plated onto cathodes (electrowinning process). It is proposed that the dilute solution, when free oF copper, could be returned and circulated up lo several limes. An automatic analytical system would maintain the required strength of the acid solution. Proponents elaim that the cost of Ihe system would be less per ton of copper produced and would increase miner safely. One factor that must he carefully tested is the possible percolation of acid solution into nearby groundwater. 

Cuprous acetylide, of which only a very small quantity may be prepared safely at one time, is procured by bubbling acetylene into an ammoniacal solution of cuprous chloride. It precipitates as a brick-red powder. The powder is collected on a small paper filter and washed with water. About 0.1 gram of the material, still moist, is transferred to a small iron crucible—the rest of the cuprous acetylide ought to be destroyed by dissolving in dilute nitric acid—and the crucible is placed on a triangle over a small flame. As soon as the material has dried out, it explodes, with a loud report, causing a dent in the bottom of the crucible. 

Although Cr03 is soluble in some organic solvents, like tert-butyl alcohol, pyridine or acetic anhydride, its use in such solvents is limited, because of the tendency of the resulting solutions to explode.2,3 Nevertheless, acetone can safely be mixed with a solution of chromium trioxide in diluted aqueous sulfuric acid. This useful property prompted the development of the so-called Jones oxidation, in which a solution of chromium trioxide in diluted sulfuric acid is dropped on a solution of an organic compound in acetone. This reaction, first described by Jones,13 has become one of the most employed procedures for the oxidation of alcohols, and represents a seminal contribution that prompted the development of other chromium (VI) oxidants in organic synthesis. 

In 1946, Jones discovered that secondary alcohols could be efficiently oxidized to ketones by pouring a solution of chromium trioxide in diluted sulfuric acid over a solution of the alcohol in acetone.13 This procedure, which has proved to be quite safe, allows a sufficient contact of the alcohol with chromium oxide derivatives for a reaction to take place. Jones oxidation marked the beginning of the highly successful saga of chromium-based oxidants. 

Why is it safe for us to use vinegar, which contains ethanoic acid, on food while it would be extremely dangerous for us to use dilute nitric acid for the same purpose ... 

The kinetics of the hydrolysis of acetic anhydride in dilute hydrochloric acid, Scheme 1.9, may be described by a single pseudo-first-order rate constant, k, and the investigation by calorimetry combined with IR spectroscopy, as we shall see in Chapter 8, provides a clear distinction between the heat change due to mixing of the acetic anhydride into the aqueous solution and that due to the subsequent hydrolysis. This model of the reaction is sufficient for devising a safe and efficient large-scale process. We know from other evidence, of course, that the reaction at the molecular level is not a single-step process - it involves tetrahedral intermediates - but this does not detract from the validity or usefulness of the model for technical purposes. 

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