Studies On Preparation Of Phenolic Resin Adhesive And Char Sulfonic Acid By Papermaking Effluent

There is a lot of lignin in waste water which is poured from papermaking factory,it will cause great pollution to the environment if we have no rational use plan.As petrochemical resources become exhausted and the require to reduce carbon emissions,improving the valueable of lignin in waste water has a great significance to solve energy and environmental issues.The purpose of this paper is to efficiently use lignin in waste water.For this purpose we have some researches as follows and get some achievements.(1)The black waste water from papermaking factory was oxidized and degraded upon catalysis with catalyst A under microwave irradiation and the phenolic hydroxyl content and average molecular weight of the degraded products was measured by UV-Vis and GPC,respectively.The effect of different additives,microwave power,the amount of A and microwave irradiation time on lignin molecular weight and phenolic hydroxyl content was checked in details and compared to lignin which is treated by ordinary heating way.Under optimized conditions,the phenolic hydroxyl content of the degraded lignin rise from 1.90 to 3.30mmol/g,its average molecular weight decrease from 2000?3000 to 800?1000.The treated effect by microwave irridiation is obviously pirroir to that by ordinary heating.(2)Using the above pretreated lignin to replace part of phenol as a raw material,its phenolation and then hydroxymethylation to synthesize lignin-phenolic resin adhesive(LPF)and lignin-furfural resin adhesive(LPFF)were studied.The effect of the replacement rate of lignin,the molar ratio of phenol and formaldehyde and the content of catalyst on the LPF adhesive was checked in details;In addition,the effect of the reaction time and temperature,the amount of furfural and formaldehyde and pH on the LPFF adhesive was examined in details by design orthogonal experiment.Under optimized conditions,the agglutination intensity of LPF adhesive reach to 4.01MPa,the agglutination intensity of LPFF adhesive is between 1.45 and 1.67 MPa.The present LPF adhesive has lower curing temperature and faster curing speed than the traditional phenolic resin adhesive,but also its residual phenol and formaldehyde are lower than the national standard.However,the agglutination intensity of LPFF remains to be further improved.(3)Using the LPF adhesive above described as as raw material,the preparation method for the LPF-based biochar sulfonic acids(LPF-SO3H)was studied in details.The effect of the carbonized temperature,the ratio of LPFC and 50%oleum,the sulfonated temperature and the reaction time on the yield,sulfonic acid amount and catalytic properties of LPF-SO3H was checked systematicall andt hen compared to the additive B-containing LPF-SO3H and the lignin-based biochar sulfonic acid(L-SO3H).Under the conditions,the sulfonic acid content of LPF-SO3H reaches to 2.28mmol/g.In catalysizing dioctyl adipate,the effect of the ratio of catalyst,adipic acid and isooctyl alcohol,the reaction temperature and the time on the esterification rate of catalyst was systematically chekced.Under the optimized conditions,the highest esterification yield of LPF-SO3H is 99.86%and its average esterification yield and recovery respectively reache to 99.07 and 90%during eight runs,showing the better catalytic performance.Notably,the introduction of the additive B into LPF-SO3H can improve the stability of sulfonic acid groups,esterification rate and recovery to some extent.But the catalytic efficiency of L-SO3H is still low due to its lower sulfonic acid content.In a word,the present research provides a novel method for the fine utilization of black liquor.