Hydrofluoric Acid - an overview | ScienceDirect Topics
A solution of HF in water is known as hydrofluoric acid. This acid is highly corrosive. HF is the principal industrial source of fluorine and a precursor to many important compounds, including pharmaceuticals and polymers such as Teflon. Hydrogen fluoride is on both the hazardous air pollutant and toxic substance lists released by the EPA.
Hydrofluoric Acid - an overview | ScienceDirect Topics
Hydrofluoric acid (HF) is a dangerous inorganic acid that is used widely in the chemical industries, electronics manufacturing, glass etching, smelting, cleaning, and other industrial fields [1–3]. It exists in two forms: in a purified form (>99%), called anhydrous hydrofluoric acid, and in a dilute form, called aqueous hydrofluoric acid [4].
Hydrofluoric Acid - an overview | ScienceDirect Topics
From a chemistry perspective, HF is the inorganic acid of elemental fluorine (Özcan et al., 2012). Hydrogen fluoride is produced by the reaction of calcium fluoride (CaF 2) and sulfuric acid. HF solutions can be formed when fluoride salts are acidified with acidic solutions. As it is a weak acid, hydrogen fluoride in water for instance is not ...
Hydrofluoric Acid - an overview | ScienceDirect Topics
Hydrofluoric acid is a highly corrosive chemical primarily causing dermal injury to the hands. Hydrofluoric acid releases free hydrogen ions (H +) that penetrate and corrode the skin, potentially down to bone, producing bone demineralization and necrosis. The respiratory effects parallel those of the skin, except effects in the lungs have a ...
Enthalpy of formation of aqueous hydrofluoric acid: Revision …
2020年1月1日 · The authors [60] specified in the text that this value corresponded to the dissolution in the acid with w(HF) = 0.19, however, the reported thermochemical equations implied w(HF) = 0.20. In this work, we adopt w(HF) = 0.19. The uncertainty for w(HF) increases U(Δ sol H° m) from 0.17 kJ⋅mol −1 to about 0.35 kJ⋅mol −1. The enthalpy of ...
Kinetic mechanics of the reactions between HCl/HF acid mixtures …
2016年8月1日 · For the HF acid-rock reaction, we assume that the reaction order is α and the reaction rate constant is k 1. If we assume that the sandstone minerals react with only the HF and the acid-rock reaction rate J and the HF concentration C HF are known, the HF reaction order α and the reaction rate constant k 1 can be obtained based on Eq. (17).
Anhydrous Hydrofluoric Acid - an overview - ScienceDirect
As an acid, HF will readily protonate water, alcohols, carboxylic acids, and other organic solutes having unshared pairs of electrons. Because the tendency for oxidation of fluoride to fluorine is very low, many inorganic and organic compounds can be fluorinated by the electrochemical insertion of F − using the HF solvent system.
Effect of hydrofluoric acid concentration and etching time on the ...
2023年1月1日 · However, HF acid etching of vitreous ceramics may negatively affect the mechanical properties of the material. The etching time and HF acid concentration may influence the shape and size of the resulting surface defects and affect both the adhesion and mechanical behavior as a consequence [15, 16].
Fluoride ion and hydrofluoric acid detection via silicon nanosheet ...
2023年10月15日 · HF acid sensing characteristics have been analyzed by using the SNFET sensor. Fig. 4 a shows the sensing mechanism of HF acid with the TISAB solution in the SNFET sensor. The diluted HF acid solutions were prepared by mixing the undiluted HF acid (HF, 49 %) with ultra-high purity (UHP) water, then the solution was mixed with TISAB solution.
A review of treatment strategies for hydrofluoric acid burns: …
2014年12月1日 · Hydrofluoric acid (HF), a dangerous inorganic acid, can cause severe corrosive effects and systemic toxicity. HF enters the human body via where it contacts, such as skin and mucosa, alimentary and respiratory tracts, and ocular surfaces. In the recent years, the incidence of HF burn has tended to increase over time.