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A new bio-adsorbent to remove reactive dyes from textile effluent was investigated in the present study. The adsorbent was the leaves of locally available hogla plant (Typha angustata). Initially, sunfix yellow, a reactive dye widely used in textile effluents, was used to check the removal efficiency in terms of contact time, pH of dye solution and adsorbent dosage. Complete removal (100%) of dye was achieved at adsorbent/dye ratio of 2300:1 at pH 10 with 180 minutes contact time. The adsorbent was then applied to deep colored, raw textile wastewater samples and it was found that 2.3 g of adsorbent was able to convert 100 mL of deep colored wastewater to transparent water at pH 10. Additionally, treatment by the adsorbent resulted in significant decreases in pH, BOD, COD, TS, TDS and TSS of wastewater, while improving the DO level.

Bangladesh is one of the top garment exporting countries of the world. In FY 2014-2015, 81.69% of Bangladesh?s export industries was comprised of ready-made garments. Dyeing industries are an integral part of most of these garment industries. Unfortunately, majority of the effluents from these dyeing industries are responsible for severe water pollution and environmental degradation as they are often discharged with no or minimal treatment. This has dire consequences as Bangladesh is a densely populated country with a soaring figure of 1252 per km2 as of 2016, based on the latest United Nations estimates. Additionally, it is a chiefly rural and river centric country and 66 % of its population are directly dependent on its rivers for either their livelihood (e.g. fishermen, oarsman) or other household activities such as washing, bathing, cooking and sometimes even drinking. This has led to an outburst of diseases like cholera, dysentery, diarrhea, hepatitis A, lead poisoning, malaria, etc prevailing for the last few years, creating a catastrophic impact on public health. This has made it imperative for wastewater to be treated properly before its release into the water bodies. Although there are a number of techniques available, most of them are expensive and so the local industries are reluctant to use these methods. In this study, it has been attempted to find a cheap and suitable method for removing dyes from these effluents. NZVI (Nano-scale Zero Valent Iron) seems to have a great potential in this aspect. It is cheap, easy to make and has a high efficiency in degrading dyes. Furthermore, only a small amount is sufficient to remove a relatively large amount of dyes, which makes it an attractive treatment method for Bangladesh.