# Application of Date Palm Tree Branch-Based Activated Carbon for Aqueous Toxicity Reduction
## 1 Introduction  
Activated carbon is widely used for many industrial and environmental applications such as gold recovery, water/wastewater treatment, and air pollution control [1]. Considering this, the production of activated carbon from a variety of materials remains a very active research area, with a special interest also noted in activated carbon production from many waste materials [2, 3]. Such efforts also support the ongoing international sustainable development efforts that focus on the 4R philosophy, i.e., reduce, recycle, reuse, and recover. To this end, the use of agricultural wastes for activated carbon production has received special attention, with many research studies reporting high-efficiency activated carbon synthesis from the respective waste materials [4, 5, 6].  
As many countries around the globe have millions of date palm trees for commercial scale date-fruit production and sales, they also generate huge agricultural waste including date pits and date palm tree branches. This is another rich bio-resource for activated carbon production. Indeed, several studies report activated carbon production from several byproducts including date pits and date palm branches [3, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28]. [PERSON] et al. [27] prepared activated carbon from agricultural by-products. The authors reported that the activation process enhances both the specific surface area and also the adsorption efficiency of the prepared activated carbon samples. With both phenol and 2,3,4-trichlorophenol in the waste stream, the adsorption of the latter was higher compared to the former, probably because of preferential adsorption. [PERSON] and [PERSON] [28] prepared activated carbon from apricot stone shells by chemical treatment with phosphoric acid. The adsorptionof various phenol-based pollutants, i.e., phenol (P), \(m\)-, \(p\)-cresol (Cr), 2-chlorophenol (2-CP), 4-nitrophenol (4-NP), 2,4-dichlorophenol (2,4-DCP), and 2,4-dinitrophenol (2,4-DNP), showed the following trend: P, Cr < 2-CP < 4-NP < 2,4-DNP < 2,4-DCP. [PERSON] et al. [13] investigated the preparation and characterization of activated carbon from date stones using physical activation with steam. The authors used date pits and pyrolysis and physical activation, to produce activated carbon. Furthermore, the effect of pyrolysis temperature and activation hold time on the textural and chemical surface properties of raw date stones and the carbon materials produced was investigated. A pyrolysis temperature of 700 \({}^{\circ}\)C, with 100 cm\({}^{3}\) per min nitrogen flow, followed by activation under water vapor at 700 \({}^{\circ}\)C for 6 h, yielded an activated carbon sample with a specific surface area of 635 m\({}^{2}\)/g and a micro-pore volume of 0.716 cm\({}^{3}\)/g. After pyrolysis, the cellulose and hemicellulose in the date pits were converted to carbon and graphite. Furthermore, though the original date pits contained several oxygen-based functional groups, after pyrolysis, aromatic groups were noted to be dominant. However, a comprehensive investigation on the application of activated carbon produced using 'date palm tree branches' for aqueous phase pollution control has not been completed to the best of our knowledge. Nevertheless, such a work would be very useful considering the fact that branches trimmed from millions of date palm trees are another rich bio-resource for activated carbon production. The present study has thus investigated the application of granular activated carbon (GAC) from waste 'date palm tree branches' for aqueous phase pollution control. To that end, the present work investigated the removal of phenol, \(p\)-cresol, and copper as they represent typical organic and inorganic (heavy metal) pollution sources in several industrial wastewater streams.