No abstract

Textile industrialization is an integral part of the economic growth in Tanzania. However, the corresponding wastewater from textile treatment processes consists of dyes and auxiliaries associated with acute toxicological impacts. This necessitates an investigation of the functional performance of the industrial treatment systems used before effluent discharge. The study primarily accesses the catalog of industrial dyes and the functionality of the treatment system at Arusha, Morogoro and Dar es Salaam vis-à-vis the effluent physicochemical properties. The analytical study reveals disperse (42%), vat (34%) and reactive (26%) as the most used industrial dyes. The physicochemical properties of the quantified wastewater reveal a significant amount of and phosphorus which was consequent to the high turbidity, biochemical oxygen demand (BOD) and chemical oxygen demand (COD) apart from the color at the different sampling points. Although the treatability of the wastewater was 90% efficient using an activated carbon system (237.33 ± 0.67 mg/L). Similarly, the use of aerated constructed wetlands shows efficiency in the remediation of the recalcitrant having a value of 12.13 ± 0.89b mg/L (90%) and 13.22 ± 0.15a mg/L (94%). Thereafter, needful recommendations were suggested based on the physicochemical properties of the textile wastewater and to improve the functionality of the treatment systems in the respective industries.

The environmental impact and denaturing propensity of organic solvents in the extraction of plant bioactives pose great challenges in extraction systems.

Effluents resulting from the frequent use of industrial azo dyes in textile operations have posed great toxicological impacts on man and the environment. The limitations of conventional treatment infrastructure necessitate the use of rapid Fenton-mediated catalytic systematic process to tackle the attendant treatment limitations. The study applied in situ Fenton-mediation process with constructed low power UV-LED reactor for rapid catalytic treatment of dye-laden effluent using enhanced acid and alkali TiO2-nanoparticles (Nps) (1–5%, i.e. 1–5 M) at definite experimental conditions, respectively. A comprehensive instrumental study was done to access the morphological, functional and elemental constituents of these nanocatalysts. The performance of the respective catalyst was evaluated using methylene blue (MB) dye at definite experimental conditions of pH, dosage, concentration and irradiation time. The results revealed a mesoporous structural nanocatalyst with increasing surface area after enhanced modification. The optimal experimental conditions of pH and concentration were recorded as 5 and 10 mg/L, respectively. While the most efficient nanocatalyst was 3 wt% alkali-modified TiO2 (3% Ak-TiO2) having a degradation efficiency of 89.15% at 90 min of irradiation using 50 mg dosage in contrast to higher irradiation time and catalyst dosage for other catalysts.

The functional impacts of polyaniline in the fabricated photocatalyst nanocomposites used in dye photocatalysis were critically investigated via spectroscopic and microscopic instrumental overview.