Knowledge

Oil and gas separators, placed deep on the ocean floor at depths of between 1,500 and 2,000 meters, suffer external hydrostatic pressures of 150 to 200 bar (15 to 20 MPa). These separators have electr

Ferric chloride (FeCl₃) etchant at 42° Bé (around 38-40% FeCl₃ by weight) is the typical medium for etching copper-clad circuit boards and for the chemical milling of metals. The solution i

The semiconductor wet benches require ultrapure water (UPW) with metal ion contamination levels of < 0.1 parts per billion (ppb) for crucial process stages such as wafer cleaning, etching and strip

The geothermal brine used for power generation and direct heating applications is a complex mixture of chlorides (10,000-30,000 ppm), carbon dioxide, hydrogen sulfide (50-500 ppm) and trace heavy meta

Salt evaporation ponds for the production of sodium chloride, potassium chloride and other salts from brines are operated at temperatures of 40-60°C and chloride concentrations from saturation (ab

Electroless nickel (EN) plating baths are run at 85-95°C, pH 4.0-5.5 and contain nickel sulfate or nickel hypophosphite as metal source, sodium hypophosphite as reducing agent and a variety of com

Mixed nitric-hydrofluoric acid solutions are used in stainless steel and titanium alloy pickling lines to remove oxide scale and surface impurities. Typical formulations comprise 10-20% HNO3 and 1-5%

Monochloroacetic acid (MCA, ClCH2COOH) is an intermediate chemical used in the synthesis of carboxymethylcellulose, surfactants and medicines. MCA is a powerful organic acid (pKa 2.85) with a chlorine

Desalters are enormous vessels used at crude oil facilities to remove salt (mostly sodium, calcium and magnesium chlorides) from crude oil prior to refining. The crude is mixed with wash water at 120-

Titanium heating coils in dilute sulphuric acid (10% H2SO4) at 80°C usually require cathodic protection or alloying with palladium (Grade 7) to stay passive. Grade 2 titanium is actively corroded

The wet-process phosphoric acid (WPA) obtained by the sulfuric acid digestion of phosphate rock contains considerable fluorine impurities (usually 1-3% as HF and H 2 SiF 6 ) which come from the fluora

Paper mill digesters employ white liquor, a solution of sodium sulfide (Na2S) and sodium hydroxide (NaOH) to delignify wood chips at 150-180°C and 8-10 bar. Titanium grade 2 is employed in heating