Cellulose Extraction and Modification Methods to Remove Heavy Metals

The water crisis and environmental problems caused by heavy metals are challenging issues that today s societies have brought. Considering that nanocellulose production is considered for reasons such as accessibility, low cost and biodegradability. In the present study, cellulose extraction and modification methods and its application in removal of heavy metals have been investigated. Considering the advantagesand disadvantages of nanofibers extraction methods, the mechanical chemical method for extracting cellulose nanofibers seems to be the safest method. High energy consumption is also a common disadvantage of all mechanical methods other than ultrasonic force and therefore is not considered as a suitable method for the production of nanocellulose. According to this study, the physical modificationagainst chemical modification is less durable, but economically has cheaper and possibly less harmful to the environment. In order to create a negative charge on cellulose, the carboxymethylation method is cost effective and is much cheaper than other methods but will result in environmental pollution, and oxidation followed by sulfurization as a green method to improve nanofibrillation of fibers is more appropriatelyevaluated. Esterification, urethanization and etherization methods can be used to remove heavy metals such as copper, chromium and nickel. The cationization can also be used to remove anionic heavy metal,and other methods for the removal of cationic heavy metals.

کلیدواژه ها:

Cellulose Extraction ، Cellulose Modification ، Heavy Metals ، Nanofibres