Protecting iron against corrosion - caused by hydrogen sulphide contg. carbon mon:oxide rich gas, using alkaline material

• Main Authors: LANG,ROLAND, JELEND,WOLFGANG,DR, KARWAT,HEINZ,DR
• Format: Patent
• Language: English; German
• Published: 05.07.1979
• Edition: 2
• Subjects: CHEMICAL SURFACE TREATMENT; CHEMISTRY; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATIONOR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; COATING MATERIAL WITH METALLIC MATERIAL; COATING METALLIC MATERIAL; DIFFUSION TREATMENT OF METALLIC MATERIAL; FUELS; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION INGENERAL; LUBRICANTS; METALLURGY; MULTI-STEP PROCESSES FOR SURFACE TREATMENT OF METALLICMATERIAL INVOLVING AT LEAST ONE PROCESS PROVIDED FOR IN CLASSC23 AND AT LEAST ONEPROCESS COVERED BY SUBCLASS C21D OR C22F OR CLASS C25; NON-MECHANICAL REMOVAL OF METALLIC MATERIAL FROM SURFACE; PEAT; PETROLEUM, GAS OR COKE INDUSTRIES; PURIFYING OR MODIFYING THE CHEMICAL COMPOSITION OF COMBUSTIBLEGASES CONTAINING CARBON MONOXIDE; TECHNICAL GASES CONTAINING CARBON MONOXIDE

Corrosion of ferrous parts of appts, which come into contact with H2S-contg. CO-rich gas mixts. in the presence of organic solvents, esp. methanol or other alcohols, is prevented by adding alkaline material (I), e.g. NaOH, NH3 or an amine, to the solvent. The method can be used to protect (a) het exchangers in plants for desulphurising methanol synthesis feed gas streams, (b) equipment used to desulphurise CO- and H2S -contg. H2 feed streams before the catalytic converter in plant for prodn. of pure H2, and (c) equipment for drying H2S- and CO-contg. gases by washing with glycol. The method allows cheaper steels to be used instead of the high alloy steels normally required.