Detoxification of Contaminated Waste Water by Acetonitrile from Liquid Chromatography by Tomato Pomace Bioadsorbent

Introduction: Acetonitrile is the most regularly operated solvents in column liquid chromatography and due to its toxicity; safe disposal method of the waste solvent is highly concerned. Many oxidation processes were investigated to degrade residues of acetonitrile in the world. Among the options in previous studies, photolysis proved to be the best choice. In current study the bio-adsorption potentials of tomato pomace for bioremediation of contaminated waste water by Acetonitrile (CAN) were investigated. The use of bio-adsorbents in room temperature for removal of toxic solvents from food/ agricultural waste offers a relatively low-cost method with a result of some oxidation processes to decompose acetonitrile in ecofriendly path. Methods: Acetonitrile residue was collected at a Research Laboratory from the Tehran Medical Sciences. The residue samples were produced after HPLC analyses of agrochemical products in organic extracts of human urine in 2019 and considering the effects of various parameters like initial concentration, contact time, agitation speed and bio-adsorbent dose were followed. The samples were analyzed by standardized international protocols and the rate of acetonitrile decomposition was measured through dissolved organic carbon (DOC) using a Shimadzu s TOC-5050 Series combustion oxidation instrument. In order to achieve a cheaper degradation procedure that could be more widely used, the system using a common light lamp (mercury vapor and tungsten filament), a Becker and a magnetic stirrer in the laboratory temperature (about 25 ± 1) were used. Results: The results revealed that, at the end of 35 minutes experiments by agitation speed of 400 rpm, the concentration of CAN decreased significantly (p < 0.05) in presence of tomato pomace with a percentage of 8.0 ± 1.1 %. The results from current detoxification of Acetonitrile by tomato pomace could be utilized to detoxification as DOC was reduced from 87.1 to 15.8 mg L-1, showing that the green chemistry method is efficient to degrade acetonitrile residues. Discussion: Authors recommend studying on the other materials from food and agricultural waste to find the best and optimum situation for cleaning up waste waters by the least possible toxic intermediates.

Keywords:

Acetonitrile , detoxification , disposal , residue , waste water