Wastewater has a high concentration of dyes and heavy metals, which are the two most significant contaminants. Due to their high toxicity and vulnerability, they possess a potential threat to human health as well as the ecosystem. There are many ways to eliminate these pollutants from water but adsorption has attained much interest because of its low cost, easy application, and no secondary pollutants. Biomass is considered an ecological burden and a reason for the reduction in the earth’s carrying capacity. These materials may be used as cost-effective adsorbents to remove dyes and heavy metals from wastewater. This paper highlights recent advances made in dye and heavy metal adsorption in the last 10 years. The prime focus of this review paper is on the direct application of these biomasses without any chemical or physical alteration. The removal efficiencies and adsorption capabilities of different biomass-derived adsorbents for the removal of dyes and heavy metals from wastewater are summarised in this study. Additionally, the adsorption mechanisms underlying the removal of dyes and heavy metals using biomass-derived adsorbents have been discussed, with a focus on two kinetic models: pseudofirst-order and pseudosecond-order. Furthermore, the Langmuir and Freundlich isotherms were utilised to verify the experimental findings and to quantify the amount and degree of adsorption favorability. Based on what has been covered in the literature, the conclusion has been drawn. The future research needs are proposed in the area of biomass-derived adsorbent development, their modification for improved efficiencies, and application on large-scale wastewater treatment plants.

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Agricultural waste materials gained attention among researchers to study the effectiveness of adsorbent media in heavy metal treatment. In this study, application of coconut shell carbon and limestone as modified adsorbent was used to remove Cr (III) from industrial wastewater. Synthetic industrial wastewater sample containing 2 mg/L of Cr (III) was prepared using distilled water and standard solution of Cr (III). Batch adsorption study was conducted to determine the effect of varied contact time (0 to 120 minutes) and pH (pH3 to pH7). The result shows that at 60 minutes of contact hour, the removal of Cr (III) from the synthetic industrial wastewater is about 98% with optimum adsorption capacity is 0.000019 mg/g at 250 rpm of agitation speed in pH5 as optimum pH. The kinetic data obtained specified that the data follow closely the pseudo-second-order. Thus, this indicates that mixing coconut shell carbon and limestone as a modified adsorbent has a potential in reducing Cr (III) concentration in industrial wastewater.

Air pollution is a global problem. It adversely affects the quality of soil, plants and water bodies. Air pollution on road side is damaging air quality on a regular basis. Previous studies and daily reports from the Ministry of Environment show that there is an increase in particle filtration in Pakistani air. To quantify the focus of specific issues pertinent to air quality this study was conducted on Jhang Road Faisalabad. Samples of dust, plants, and water were collected along the road and analysis of selected heavy metals (Cd, Cu, Ni and Pb) was done. Pollution data near se-lected sites and the effect of selected air pollution on the growth parameters of the selected plant were recorded. The concentrations of Cu (1.95mg kg -1 ), Pb (0.858mg kg -1 ) and Cd (0.735mg kg -1 ) in maize crop were the highest in the Babu Wala area of Jhang Road and Ni concentration was the highest (4.525mg kg -1 ) in the Said Abad site. The concentrations of Cu and Cd in the dust collected from Babu Wala were2.14 and 0.80mg kg -1 , respectively. The concentration of Ni was the highest (2.32mg kg -1 ) in the Risala Wala area and the concentration of Pb (0.98mg kg -1 ) was the highest at the Said Abad site. In the Risala Wala area, Cu and Cd concentration in irrigation water was 0.15 and 0.11mg L -1 , respectively. However, the Ni and Pb concentrations in irrigation water were found higher in Liaqat Abad area than any other area. The concentration of heavy metals was maximum in samples collected from road side and the concentration decreases as we move away from the road.