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Standard Water Treatment Techniques and Their Applicability to Oil and Gas Produced Brines of Varied Compositions
Published in Olayinka I. Ogunsola, Isaac K. Gamwo, Solid–Liquid Separation Technologies, 2022
Nicholas Siefert, Madison Wenzlick
Activated carbon is typically labeled as granular activated carbon (GAC) or powdered activated carbon (PAC). GAC is typically easier to regenerate than PAC. Typically, GAC is regenerated via thermal mechanisms, by which organic matter absorbed onto the pores is thermally oxidized, freeing up the surface. It should be noted that up to 10% of the carbon itself can be oxidized, meaning that there will need to be some make-up of activated carbon even when using regeneration techniques [83]. Thermal regeneration is mostly effective for organic matter absorbed onto the carbon, but care must be taken if the activated carbon also absorbs heavy metals and NORM.
Adsorption and Desorption Aspects of Carbon-Based Nanomaterials: Recent Applications for Water Treatments and Toxic Effects
Published in Uma Shanker, Manviri Rani, Liquid and Crystal Nanomaterials for Water Pollutants Remediation, 2022
Patricia Prediger, Melissa Gurgel Adeodato Vieira, Natália Gabriele Camparotto, Tauany de Figueiredo Neves, Paula Mayara Morais da Silva, Giani de Vargas Brião
Activated carbon is the most popular adsorbent due to its porosity and surface area decorated with different chemical groups. However, the high cost and limited reusability of activated carbon limit its broad application. Thus, it is necessary to develop new low-cost adsorbents that have a larger surface area and a superior performance than activated carbon. Nanomaterials are suitable candidates to adsorb several pollutants from water. These materials have at least one of their dimensions at a nanometric scale, and their key property is the exponential increase in specific surface area which enhances the ratio between surface/internal atoms. Because of that several nanomaterials have been used as adsorbents for water purification, such as metallic and metal oxides nanoparticles, MXenes, h-boron nitride, layered double hydroxides, silicon nanomaterials, nanofibers, nanoclays, polymer-based nanomaterials, zeolites, nanogels, and carbon-based nanomaterials (CBNs) (Elessawy et al. 2020a). In the last decade, CBNs emerged as efficient adsorbents due to their outstanding properties, high abundance, low cost, ease of preparation, regeneration and reusability, and benign nature. CBNs include a series of materials, but this chapter is focused on crystalline framework materials including graphene derivatives, carbon nanotubes (CNT), nanoporous carbon (NPC), nanodiamond (ND), fullerenes, and graphitic carbon nitride (CN) and their composites.
Removing PFAS from Water
Published in David M. Kempisty, LeeAnn Racz, Forever Chemicals, 2021
Caitlin Berretta, Thomas Mallmann, Kyle Trewitz, David M. Kempisty
GAC has a long history of use in the water treatment industry. Historical documents in Sanskrit text describe the use of GAC’s precursor, charcoal, in the treatment of water (EPA, 2000). In the United States, activated carbons were used beginning in the 1930s for water treatment (Le Cloirec and Faur, 2006). Activated carbon is a highly porous, carbonaceous-based media with a high affinity for organic contaminants. It has an immense internal surface area; for example, a spoonful of activated carbon has an internal surface area equivalent to an entire football field. It can be manufactured from a wide variety of carbonaceous materials, but some common sources include various ranks of coal (e.g., bituminous, sub-bituminous, lignite, and anthracite), wood, and coconut shells. The EPA has named GAC the ‘Best Available Technology’ for organic contaminant removal (Pontius, 1995). As such, not only is GAC effective for PFAS removal, it is also effective at concurrently removing other regulated or soon-to-be regulated organic compounds (e.g., chlorinated solvents, pharmaceuticals, personal care products, etc.). To that end, the presence of other organics in the water can also impact performance as they compete with PFAS chemicals for adsorption sites. Therefore, it is important to understand the total organic carbon (TOC) concentration in the feed water when designing a GAC system.
Adsorption of organic acids from offshore produced water using microporous activated carbon from babassu pericarp: a low-cost alternative
Published in Chemical Engineering Communications, 2023
Felipe Santos Mônaco, Deborah Victória Alves de Aguiar, Gerlon de Almeida Ribeiro Oliveira, Boniek Gontijo Vaz, Luciano Morais Lião, Laiane Alves de Andrade, Indianara Conceição Ostroski
Different types of materials have been studied in the adsorption of naphthenic acids, such as activated carbon from different sources (Islam et al. 2018; Niasar et al. 2019; Santos et al. 2021), biochar made from biomass (Samrat Alam et al. 2016; Bhuiyan et al. 2017), modified biopolymer (Arshad et al. 2016), zeolite, alumina, and silica (Azad et al. 2013), xerogel (Benally et al. 2019), and cellulose and polymers (Mohamed et al. 2015). Among the possible adsorbent candidates, activated carbon has become one of the most used due to its low cost and excellent removal ability (Santos et al. 2020; Carvalho et al., 2021). Regarding activated carbon, it is worthy to mention that the raw material used, the physical and chemical agents, and the operating conditions of the activation process will be the key factors that it will influence directly the properties of the material (Elsayed et al. 2017).
Assessment of thermal regeneration of spent commercial activated carbon for methylene blue dye removal
Published in Particulate Science and Technology, 2021
Muhamad Zulhelmie Mohd Nasir, Guruumurthiy Indiran, Muhammad Abbas Ahmad Zaini
The treatment dyes-containing wastewater is challenging when factors such as removal efficiency, feasibility, economic and maintenance are taken into consideration. In general, the removal strategies can be categorized as physical, chemical and biological methods, or combination of any of these methods. Among others, adsorption is a preferable technique to treat dyes-containing wastewater because the method is cheap, simple, effective, and easy to maintain, operate and scale-up (Malik 2004; Fabon et al. 2013; Popuri and Guttikonda 2015; Obaid, Abdullah, and Idan 2016). Adsorption onto activated carbon has proven to yield high removal capacity of water pollutants even at trace concentrations. Activated carbon is widely used as adsorbent in water and air pollution abatement, sugar refining, chemical and pharmaceutical industries. However, due to the high price of commercially available activated carbon, the attention has now shifted toward low-cost precursor to manufacture activated carbon and regeneration of spent commercial activated carbon for repetitive use. In a home water filter system, commercial activated carbon is used as adsorbent to purify tap water via point-of-use and point-of-entry (Amuda and Ibrahim 2006). After one to two years of service, the exhausted activated carbon will be replaced with the new one, while the spent will normally be discarded. The re-utilization of spent commercial activated carbon for wastewater treatment could be possible if suitable regeneration strategies are carried out.
Effect of calcite/activated carbon-based post-combustion CO2 capture system in a biodiesel-fueled CI engine—An experimental study
Published in Energy Sources, Part A: Recovery, Utilization, and Environmental Effects, 2019
Thiyagarajan Subramanian, Ankit Sonthalia, Edwin Geo Varuvel
In the present work, a chamber was designed with an outer shell diameter of 109 mm and lengthof 280 mm as shown in Figure 1. Four wire meshes were placed at equal intervals in the center compartment with length 100 mm. The design of the chamber was such that the back pressure could be minimized and adsorption could be maximized. The activated carbon or calcite was placed on these wire meshes. Activated carbon is a form of carbon which is processed with oxygen such that millions of tiny pores are formed in between carbon atoms which increase the surface area for adsorption (Conesa, Sakurai, and AntalJr 2000). It is produced from carbonaceous materials such as wood, nutshells, coal, and lignite (Hayashi et al. 2002). The activated carbon for the present work was purchased from a water treatment system-developing company. Calcite is found in sedimentary rocks, particularly limestone. It is formed from the shells of dead marine organisms. Studies (Arif et al. 2017; Bikkina 2011; Farokhpoor et al. 2013) show that calcite can be used to capture carbon and store for a long time; however, as per the authors’ knowledge, no study exists on its use in internal combustion engines for capturing CO2 emission.