| 摘要 |
Disclosed is a process for reducing formaldehyde content of a gas, comprising contacting said gas with a basic aqueous oxidizing solution comprising hydrogen peroxide, a metal cation (such as those chosen from Ca2+, Mg2+, Fe2+, Cu2+, Ni2+, Mn2+, Ti4+, Cr3+, Ce3+, Zn2+, Pd2+, Mo6+ and combinations thereof), and a sequestering agent (such as diethylenetriaminepentaacetic acid (DTPA), nitrolotriacetic acid (NTA), ethylenediaminetetraacetic acid (EDTA), sodium hexametaphosphate, sodium citrate and combinations thereof), so as to obtain a mixture and to oxidize at least a part of said formaldehyde contained in said gas into formic acid, wherein during said process the pH of said mixture is maintained at a value of about 9.0 to about 10.5 by addition of an alkaline solution (comprising a base such as NaOH, KOH, Mg(OH)2, Ca(OH)2, Na2CO3, NaHCO3, K2CO3, KHCO3, and combinations thereof), thereby obtaining a gas having a reduced content in formaldehyde as compared to said gas before contacting it with said oxidising solution, and a solution comprising formic acid. Further disclosed is a method for manufacturing wood-based panel products comprising mixing wood particles with a formaldehyde-containing resin, pressing the obtained mixture so as to obtain said wood-based panel products and treating a formaldehyde-containing gas released during said mixing and/or pressing step, wherein said formaldehyde-containing gas is treated by a process as defined above.
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