一株降解苯酚微生物的研究

从污泥中分离出可在舍100mg/L苯酚的LIB培养基上生长的菌株，其中JF-2生长情况最好。通过逐级驯化，JF-2的降解苯酚能力明显提高，可在以苯酚为唯一碳源的培养基中降解苯酚并生长。在接种量为1％时，JF－2在24h内将300mg／L的苯酚完全降解。该菌的最适生长和降解温度为30℃，并能在pH5．5～9内降解苯酚。河水中的天然微生物降解苯酚的能力弱，需7天才可将200mg/L的苯酚完全降解。     

用于生物降解酚类毒物的固定化细胞性能改进的研究

在获得了一种耐酚能力达915mg/L的菌种的基础上,进一步研究了以海藻酸钠包埋法制得的该菌种固定化细胞的性能。同时,采用了2种方法,即添加硅藻土和用己二胺-戊二醛对固定化细胞表面进行化学处理,使固定化细胞的机械强度,降酚活性,稳定性均得到了提高。实验证明这2种方法都有令人满意的效果。      

Degradation of phenol in mists by a non-thermal plasma reactor

A link tooth wheel-cylinder non-thermal plasma reactor was set up to investigate the degradation of phenol in the mists. In addition, the decomposition efficiency of phenol, TOC removal, and byproduct formation were investigated. The stable discharge was achieved in both air and the mist condition. The decomposition efficiency and TOC removal increased with increasing the input power. For the input power of 3.6 W, the phenol decomposition and TOC removal reached 90% and 47%, respectively. Phenol degradation byproducts were identified as small molecular organic acids, including formic acid, acetic acid, and oxalic acid. Their masses in the trapped solutions first increased and then decreased slightly with increasing the input power. Therefore, the biodegradation capacity of the phenol degradation byproducts can be improved.     

荧光分光光度法测定天然水中的挥发酚

天然水经过蒸馏后,直接用荧光分光光度计进行测定。激发波长为２７５ｎｍ,最佳发射波长为２９８ｎｍ,可定量测定水中的挥发酚。该方法灵敏、准确、节省试剂、简便易行,方法最低检出限可达２μｇ／Ｌ     

Application of a chemically modified green macro alga as a biosorbent for phenol removal

Phenol and substituted phenols are toxic organic pollutants present in tannery waste streams. Environmental legislation defines the maximum discharge limit to be 5–50 ppm of total phenols in sewers. Thus the efforts to develop new efficient methods to remove phenolic compounds from wastewater are of primary concern. The present work aims at the use of a modified green macro alga (Caulerpa scalpelliformis) as a biosorbent for the removal of phenolic compounds from the post-tanning sectional stream. The effects of initial phenol concentration, contact time, temperature and initial pH of the solution on the biosorption potential of macro algal biomass have been investigated. Biosorption of phenol by modified green macro algae is best described by the Langmuir adsorption isotherm model. Biosorption kinetics of phenol onto modified green macro algal biomass were best described by a pseudo second order model. The maximum uptake capacity was found to be 20 mg of phenol per gram of green macro algae. A Boyd plot confirmed the external mass transfer as the slowest step involved in the biosorption process. The average effective diffusion coefficient was found to be 1.44 × 10⁻⁹ cm²/s. Thermodynamic studies confirmed the biosorption process to be exothermic.     

Adsorption enhancement of laterally interacting phenol/aniline mixtures onto nonpolar adsorbents

Adsorption equilibria of phenol and aniline onto nonpolar macroreticular adsorbents were investigated in single and binary-solute aqueous systems at 293 K and 313 K. All adsorption isotherms can be well represented by the Langmuir equation. Larger uptake of aniline than phenol onto all the adsorbents probably results from the higher hydrophobicity of the former compound as well as the greater electronic density of the aromatic ring of aniline. It is interestingly observed that at a relatively high loading, the total uptake of phenol and aniline in a binary system is remarkably higher than those in a single system. Such uptake difference was elucidated by the cooperative effect arising from the lateral acid–base interaction between the loaded phenol and aniline molecules. Moreover, larger average pore size of the adsorbent is found to result in a greater cooperative coefficient, as observed from the equimolar phenol/aniline adsorption system.     

Enhanced degradation of organic contaminants using catalytic activity of carbonaceous structures: A strategy for the reuse of exhausted sorbents

Generation of hydroxyl radicals (?OH) is the basis of advanced oxidation process (AOP). This study investigates the catalytic activity of microporous carbonaceous structure for in-situ generation of ?OH radicals. Biochar (BC) was selected as a representative of carbon materials with a graphitic structure. The work aims at assessing the impact of BC structure on the activation of H₂O₂, the reinforcement of the persistent free radicals (PFRs) in BC using heavy metal complexes, and the subsequent AOP. Accordingly, three different biochars (raw, chemically- and physiochemically-activated BCs) were used for adsorption of two metal ions (nickel and lead) and the degradation of phenol (100 mg/L) through AOP. The results demonstrated four outcomes: (1) The structure of carbon material, the identity and the quantity of the metal complexes in the structure play the key roles in the AOP process. (2) the quantity of PFRs on BC significantly increased (by 200%) with structural activation and metal loading. (3) Though the Pb-loaded BC contained a larger quantity of PFRs, Ni-loaded BC exhibited a higher catalytic activity. (4) The degradation efficiency values for phenol by modified biochar in the presence of H₂O₂ was 80.3%, while the removal efficiency was found to be 17% and 22% in the two control tests, with H₂O₂ (no BC) and with BC (no H₂O₂), respectively. Overall, the work proposes a new approach for dual applications of carbonaceous structures; adsorption of metal ions and treatment of organic contaminants through in-situ chemical oxidation (ISCO).     

Microwave and Fenton's reagent oxidation of wastewater

We compared two H₂O₂ oxidation methods for the treatment of industrial wastewater: oxidation using Fenton's reagent [H₂O₂/Fe(II)] and microwave irradiation. Both methods were applied to the treatment of synthetic phenol solutions (100 mg L⁻¹) and of an industrial effluent containing a mixture of ionic and non-ionic surfactants at high load (20 g L⁻¹ of COD). The effects of initial pH, initial H₂O₂ concentration, Fenton catalyst amount and irradiation time were assessed. According to the oxidation of phenol, it has been found that the oxidation by Fenton's reagent is dependent on the pH, contrary to the microwave system, which is not influenced by this parameter. For both systems, a limiting amount of oxidant has been found; above this point the oxidation of phenol is not improved by a further addition of peroxide. The oxidation of the industrial surfactant effluent has only been successful with the Fenton's reagent. In this case, large amounts of ferrous ions are necessary for the precipitation of the ionic surfactants of the effluent, followed by the oxidation of the non-ionic constituents of the solution. Electronic Publication     

Investigation of the usage of centrifuging waste of mineral wool melt (CMWW), contaminated with phenol and formaldehyde,in manufacturing of ceramic products

Large amounts of centrifuging waste of mineral wool melt (CMWW) are created during the production of mineral wool. CMWW is technogenic aluminum silicate raw material, formed from the particles of undefibred melt (60–70%) and mineral wool fibers (30–40%). 0.3–0.6% of organic binder with phenol and formaldehyde in its composition exists in this material. Objective of the research is to investigate the possibility to use CMWW as an additive for the production of ceramic products, by neutralising phenol and formaldehyde existing in CMWW. Formation masses were prepared by incorporating 10%, 20% and 30% of CMWW additive and burned at various temperatures. It was identified that the amount of 10–30% of CMWW additive influences the following physical and mechanical properties of the ceramic body: lowers drying and firing shrinkage, density, increases compressive strength and water absorption. Investigations carried out show that CMWW waste can be used for the production of ceramic products of various purposes.     

酚类、醇类抑制斜生栅列藻生长的毒性效应

以生物监测方法，利用国际标准指示生物斜生栅列藻研究酚及其衍生物和丁醇其异构体的急性毒性规律。试验表明，苯酚衍生物的毒性比母体强得多，而后者的毒性比丁醇及异构体更大。