Sepg. or reducing oxygen@, nitrite and/or nitrate content contained in water - by treating with hydrogen@, using catalyst comprising palladium, rhodium or copper

摘要

Process comprises treating the water with H2 and contacting it with a catalyst comprising Pd and/or Rh or Pd and a metal of the Cu gp., impregnated in a carrier. The carrier consists of Al2O3 of ''theta'' and ''kappa'' modifications with no or only a small amt. of ''alpha'' modification, and free from ''gamma'' and ''delta'' modifications; the carrier has either a pore dia. monomodal distribution showing one max. in the 700-1500 (800-1250) Angstroms range. For treating water contaminated only with nitrite the catalyst comprises metal components from Pd and/or Rh, and if the water also contains metals, then the metal components comprise Pd and a Cu gp. metal or Rh and opt. Pd, or a mixt. of these catalysts. The pH value of the value is at most 8 and the process is repeated until oxygen, nitrite and/or nitrate contents are nil or of tolerable value. USE/ADVANTAGE - The catalyst/carrier is abrasion resistant