효소 고정화 막 생물반응기(EMBRs)는 폐수 내의 염료를 처리하는 새로운 방법입니다. 이 분야는 효소의 효능과 환경에 대한 높은 저항성 때문에 많은 양의 연구가 진행되었습니다. 효소 자체와 해당 효소의 구조를 모두 포함하는 다양한 방법이 EMBR에 접근할 수 있습니다. 생물반응기 자체는 염료 제거의 필요에 맞게 변형될 수 있습니다. 효소적 생물반응기 부터 산화 그래핀 또는 탄소 나노튜브와 같은 나노구조를 사용하는 것까지 다양합니다. 또한 TiO2와 같은 나노입자는 EMBR 을 더욱 향상시키기 위해 사용될 수 있습니다. 폴리머 기반의 막 지지 구조는 또한 효능 증가의 문제에 접근하는 다양한 방 법을 포함합니다. 본 바와 같이, 지난 수십 년 동안 EMBR을 사용하는 이 문제에 대한 다양한 접근법이 수행되었습니다. 이 검토는 방법론을 요약하고 EMBR에 대한 다양한 개선 사항을 설명하는 것을 목표로 합니다.

Green synthesis of graphene using leaf extracts as sustainable reducing and capping agents is a thrust area of research owing to its simplicity, eco-friendly nature and the ease of access to graphene. Moringa (Moringa oleifera Lam) plant is widely cultivated in India owing to its important medicinal and nutritional values. Inspired by these reports, herein we report a simple, green and economic synthesis of graphene, Moringa leaf extract employed reduced graphene oxide (MRGO) with excellent dye removal efficiencies. The MRGO is prepared by refluxing a mixture of aqueous dispersion of graphene oxide and Moringa leaf extract for 10 h. Further, we elucidated the role of synthesized MRGO in the removal of methylene blue (MB) and rhodamine B (RB) dyes through the sonochemical method. This as-synthesized material exhibited excellent dye removal efficiencies of about 93% and 87% against MB and RB dyes, respectively. Graphene with huge surface area expedited the better adsorption of dye molecules, thus, facilitated the better removal of the latter. Therefore, the superior dye removal efficiencies of MRGO were attributed to its adsorption capacity. This cost-effective synthetic approach of MRGO nanomaterial has a great potential for the innovative applications in water purification technology and find its place in further industrialization.

Environmental pollution remains a considerable health risk source all over the world; however, hazards are usually higher in developing countries. Iraq has long been suffering from the problem of pollution and how to treat pollution. Photocatalytic degradation has turned out to be most productive process for dye degradation. In this investigation, Rhodamine B (RhB), dye has been selected for degradation under visible light illumination. To address this issue, we fabricate erbium trioxide nanoparticles (Er2O3/NPs). Erbium trioxide nanoparticles are prepared and utilized for photo-catalytic degradation. The characterization of Er2O3/NPs is described and confirmed by utilizing of XRD (X-ray diffraction) and SEM (Scanning Electron Microscopy). The average size of Er2O3 nanoparticles is observed to be 16.00 nm. Er2O3/NPs is investigated for its ability of photo-catalytic degradation through certain selected parameters such as concentration and time. The methodological results show that the synthesized Er2O3/NPs is a good photo-catalytic for Rhodamine degradation.

Orange peel (OP) exhibits a sorption capacity towards anionic dyes such as reactive blue 19 (RB19). Cetyltrimethylammonium bromide (CTAB) as a cationic surfactant was used to modify the surface nature of OP to enhance its adsorption capacity for anionic dyes from an aqueous solution. Four adsorbents were investigated: the OP, sodium hydroxide-treated OP (SOP), CTAB-modified OP and CTAB-modified SOP. The physical and chemical properties of these sorbents were determined using nitrogen adsorption at 77 K and by scanning electron microscope and Fourier transform infrared spectroscopy techniques. The adsorption of the RB19 dye was assessed with these sorbents at different solution pH levels and temperatures. The effect of the contact time was considered to determine the order and rate constants of the adsorption process. The adsorption data were analyzed considering the Freundlich, Langmuir, Elovich and Tempkin models. The adsorption of RB19 by the assessed sorbents is of the chemisorption type following pseudo-first-order kinetics. CTAB modification brought about a significant increase in RB19 adsorption, which was ascribed to the grafting of the sorbent with a cationic surfactant.

Four activated carbons were produced by two-stage process as followings; semi-carbonization of indigenous biomass waste, i.e. cotton stalks, followed by chemical activation with KOH under various activation temperatures and chemical ratios of KOH to semi-carbonized cotton stalks (CCS). The surface area, total pore volume and average pore diameter were evaluated by N2-adsorption at 77 K. The surface morphology and oxygen functional groups were determined by SEM and FTIR, respectively. Batch equilibrium and kinetic studies were carried out by using a basic dye, methylene blue as a probe molecule to evaluate the adsorption capacity and mechanism over the produced carbons. The obtained activated carbon (CCS-1K800) exhibited highly microporous structure with high surface area of 950 m2/g, total pore volume of 0.423 cm3/g and average pore diameter of 17.8 a. The isotherm data fitted well to the Langmuir isotherm with monolayer adsorption capacity of 222 mg/g for CCS-1K800. The kinetic data obtained at different concentrations were analyzed using a pseudo-first-order, pseudo-second-order and intraparticle diffusion equations. The pseudo-second-order model fitted better for kinetic removal of MB dye. The results indicate that such laboratory carbons could be employed as low cost alternative to commercial carbons in wastewater treatment.

The adsorption of Acid Blue 92 onto three low cost and ecofriendly biosorbents viz., cow dung ash, mango stone ash and parthenium leaves ash and commercial activated carbon have discussed in this work. The ash of all the mentioned bio-wastes was prepared in the muffle furnace at 500℃ and all the adsorbents were stored in an air thermostat. Experiments at total dye concentrations of 10~100 mg/L were carried out with a synthetic effluent prepared in the laboratory. The parameters such as pH and dye concentration were varied. Equilibrium adsorption data followed both Langmuir and Freundlich isotherms. The results indicate that cow dung ash, mango stone ash and parthenium leaves ash could be employed as low-cost alternatives to commercial activated carbon in wastewater treatment for the removal of dye.

The aim of this research was to evaluate the performance of insoluble electrode for the purpose of degradation of Rhodamine B (RhB) and oxidants generation [N,N-Dimethyl-4-nitrosoaniline (RNO, indicator of OH radical), O3, H2O2, free Cl, ClO2)]. Methods: Four kinds of electrodes were used for comparison: DSA (dimensional stable anode; Pt and JP202 electrode), Pb and boron doping diamond (BDD) electrode. The effect of applied current (0.5～2.5 A), electrolyte type (NaCl, KCl and Na2SO4) and electrolyte concentration (0.5～3.5 g/L) on the RNO degradation were evaluated. Experimental results showed that the order of RhB removal efficiency lie in: JP202 > Pb > BDD ≒> Pt. However, when concerned the electric power on maintaining current of 1 A during electrolysis reaction, the order of RhB removal efficiency was changed: JP202 > Pt ≒ Pb > BDD. The total generated oxidants (H2O2, O3, free Cl, ClO2) concentration of 4 electrodes was Pt (6.04 mg/W) > JP202 (4.81 mg/W) > Pb (3.61 mg/W) > BDD (1.54 mg/W), respectively. JP202 electrode was the best electrode among 4 electrodes from the point of view of performance and energy consumption. Regardless of the type of electrode, RNO removal of NaCl and KCl (chlorine type electrolyte) were higher than that of the Na2SO4 (sulfuric type electrolyte) RNO removal. Except BDD electrode, RhB degradation and creation tendency of oxidants such as H2O2, O3, free Cl and ClO2, found that do not match. RNO degradation tendency were considered a simple way to decide the method which is simple it will be able to determinate the electrode where the organic matter decomposition performance is superior. As the added NaCl concentration was increases, the of hydrogen peroxide and ozone concentration increases, and this was thought to increase the quantity of OH radical.