Bioprocessing strategies for cost-effective simultaneous removal of chromium and malachite green by marine alga Enteromorpha\xa0intestinalis

Ragaa A Hamouda,Noura El-Ahmady El-Naggar,Nada M Doleib,Amna A Saddiq

doi:10.1038/s41598-020-70251-3

Abstract

A large number of industries use heavy metal cations to fix dyes in fabrication processes. Malachite green (MG) is used in many factories and in aquaculture production to treat parasites, and it has genotoxic and carcinogenic effects. Chromium is used to fix the dyes and it is a global toxic heavy metal. Face centered central composite design (FCCCD) has been used to determine the most significant factors for enhanced simultaneous removal of MG and chromium ions from aqueous solutions using marine green alga Enteromorpha intestinalis biomass collected from Jeddah beach. The dry biomass of E. intestinalis samples were also examined using SEM and FTIR before and after MG and chromium biosoptions. The predicted results indicated that 4.3 g/L E. intestinalis biomass was simultaneously removed 99.63% of MG and 93.38% of chromium from aqueous solution using a MG concentration of 7.97 mg/L, the chromium concentration of 192.45 mg/L, pH 9.92, the contact time was 38.5 min with an agitation of 200 rpm. FTIR and SEM proved the change in characteristics of algal biomass after treatments. The dry biomass of E. intestinalis has the capacity to remove MG and chromium from aquatic effluents in a feasible and efficient manner.

Highlights

A large number of industries use heavy metal cations to fix dyes in fabrication processes
The biosorption processes are complicated systems and their performance is greatly affected by various physicochemical process parameters such as pH, temperature, etc
The results show significant differences in the percentages of chromium and Malachite green (MG) removal by E. intestinalis based on the variation of the five variables

Summary

Introduction

A large number of industries use heavy metal cations to fix dyes in fabrication processes. Chromium is used to fix the dyes and it is a global toxic heavy metal. Heavy metals and dyes are used in many industries like, energy and fuel production, leather tanning, etc. All these industries discharge large quantities of toxic wastes directly or indirectly into the environment with untreated effluents which cause a serious environmental pollution and endangering human life[4,5,6]. Due to the extensive use of Cr in a wide range of industries[11,12]; the consequent environmental pollution of chromium has increased, causing the greatest concern in the last recent y ears[13]

Methods

Results

Conclusion