| Biomimetic catalyst has characteristics of both enzymatic catalyst and chemical catalyst. Therefore, it is an efficient approach of green chemistry in pulping. In this paper, the influence of wheat straw pulping properties on the pretreatment by GIF biomimetic system was investigated in detail. The treatment of effluent by Fe-CA biomimetic system combined with activated sludge process was also studied. After Fe-CA biomimetic treatment the lignin and its derivatives in the effluent were removed by dehydrogenation copolymerization with coniferyl alcohol catalized by laccase throughGIF system which is composed of Copper(II)/Pyridine/Hydrogen peroxide is one of the most promising biomimetic system. The GIF system simulates the function of laccase whose active center of oxidation is coordinated copper cation. In this research, cellulolytic enzyme lignin (CEL) of wheat straw was treated by the GIF system. Infrared spectra and GC-MS analysis were used to analyze the change of chemical structure of CEL after reaction. The mechanism of this biomimetic degradation process was discussed. The results showed that the degradation of CEL was very efficient with the copper(Ⅱ)/pyridine/peroxide system. According to structure of the products, it was proved that the following three types of reaction were caused by the GIF system: oxidative cleavage of C-H bond of the aromatic ring and side chain, Cα-Cβcleavage of lignin structural units, the opening of aromatic ring.Wheat straw was pretreated by GIF system in order to improve the efficiency of CMP pulping. The effects of biomimetic treatment on chemical composition and micromorphology of wheat straw were investigated. The results showed that the optimal condition of pretreatment was as follows:CuSO4 3mmol/kg wheat straw;H2O2 31.5g/kg wheat straw; Temp. 30℃; Reaction time 4h. The results showed that contents of Klasson lignin, ash and alcohol-benzene extractives decreased after the treatment. The content of Klasson lignin decrease from from 17.4% to 14.0% after the treatment..When the charge of CuSO4 and H2O2 increased, the content of Klason lignin decline rapidly at first stage. Then the change became slow. However, holocellulose content increased from 71.7% to 75.1% by GIF treatment.. Through analysis of SEM image, it was known that the surface of treated wheat straw became rough and porous.Some fiber framework could also be observed. It was suggested that biomimetic treatment not only removed a part of lignin efficiently, but also degraded wax and fatty acid on the surface of wheat straw. The pores could provide more channels and reduce the resistance of penetration of chemicals in the consequent CMP pulping. The biomimetic degradation was proved to be an effective pretreatment method for CMP pulping of wheat straw.Most of the lignin in effluent was removed by acidification. Theneffluent from papermill was treated by Fe-based biomimetic condensation combined with coagulation in this thesis. A stable and high efficiency Fe2+-carboxyl acid complexes (Fe-CA) which could simulate the lignin peroxidase was applied to treat the papermill wastewater by rapid oxidation followed by flocculation treatment. In this research work, effluent from CMP process was treated by Fe-based biomimetic condensation and degradation followed by Al2(SO4)3-APAM flocculation. The removal ratio of pollutant substances such as CODCr, SS were over 55%, 60% respectively. Therefore, the biodegradability of the wastewater after treatment was also improved. The results proved that the operation of biomimetic treatment process was favorable for further bio-treatment of the effluent, because most lignin derivatives in the effluent were removed through condensation reaction followed by coagulation. The results showed that Fe-biomimetic system had marked effect on wastewater treatment form wheat straw CMP process. The optimal condition was as follow: Fe-CA 10g/m3, H2O2 150g/m3, Al2(SO4)3(18H2O) 300g/m3, APAM 5g/m3, reaction time 1hr and sedimentation 3hrs. The process is characterized by simple equipment, easy control, low operation cost and enduring high pollution load. The final wastewater can reach discharge standards after biochemical treatment.The effluent after biochemical treatment was characterized by higher colourity. Laccase is a kind of powerful enzyme that is promising in pulping and papermaking industry. Because it can catalyze the polymerization and oxidative degradation of lignin. It has been proved that soluble lignin and its derivatives could be degraded, or polymerized, and removed through treatment with laccase followed by coagulation. Its merit is mild reaction condition, many advantages in the requirements for reaction condition and related equipments. A novel wastewater treatment system which consists of laccase catalyzer and coniferyl alcohol was developed. When coniferyl alcohol was added, it was found to polymerize with water soluble lignin. Thus the system produced high molecule hydrophobic lignin polymers. The experiment showed that addition of coniferyl alcohol could remove soluble lignin and its derivatives in the wastewater effectively under the existence of laccase. The result also showed that the optiomal treatment condition was as follows: coniferyl alcohol dosage 0.0788g/L; laccase consumption 14.72IU/L; temperature 25℃; reaction time 1h. The removel ratios for lignin reached 81%. CODCr removal reached 68.1%. The chroma was removed by 69%.
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