Bagasse-based adsorbent with nitric acid esterification and Fe(iii) chelation for the highly efficient removal of low concentration phosphate from water

In this study, we demonstrate a one-step method for fabricating a novel sodium alginate-polyacrylamide (Alg–PAM) composite aerogel, which exhibits a very high affinity and selectivity towards Pb2+. The as-prepared Alg–PAM composite aerogel can uptake 99.2% of Pb2+ from Pb2+-containing aqueous solution (0.1 mM) and the maximum adsorption capacity for Pb2+ reaches 252.2 mg/g, which is higher than most of the reported Pb2+ adsorbents. Most importantly, the prepared Alg–PAM adsorbent can be regenerated through a simple acid-washing process with only a little loss of the adsorption performance after five adsorption–desorption cycles. In addition, the influence of the experimental conditions, such as the solution pH, contact time, and temperature, on the adsorption performance of the Alg–PAM adsorbent was studied. It is clear that the low-cost raw materials, simple synthesis, regeneration ability, and highly efficient removal performance mean that the designed Alg–PAM aerogel has broad application potential in treating Pb2+-containing wastewater.

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Study of an adsorption method for trace mercury based on Bacillus subtilis

Open Chemistry ◽

10.1515/chem-2021-0099 ◽

2021 ◽

Vol 19 (1) ◽

pp. 1164-1170

Author(s):

Yijin Li ◽

Shanhong Xia

Keyword(s):

Bacillus Subtilis ◽

Optical Microscopy ◽

Functional Groups ◽

Adsorption Mechanism ◽

Adsorption Process ◽

Mercury Determination ◽

Adsorption Efficiency ◽

Adsorption Method ◽

Adsorption Performance ◽

Highly Efficient

Abstract In order to decrease the difficulty in trace mercury determination, an adsorption method for trace mercury based on Bacillus subtilis cells was proposed in this article. The adsorption process was characterized by optical microscopy and SEM. The adsorption mechanism was analyzed by IR. The adsorption performance was studied by measuring the concentration of supernate and calculating the adsorption efficiency. When adsorbing Hg2+, Bacillus subtilis cells gathered and their structure turned coarse. The IR results illustrated that functional groups bound with Hg for complexation during adsorption. Bacillus subtilis completed adsorption for trace Hg2+ in 15 min. The adsorption efficiency was maintained above 80% under low Hg2+ concentrations (<200 µg/L). The proposed study illustrates that Bacillus subtilis cells are highly efficient and easily obtained material for the adsorption of trace mercury, which shows potential to be further used in the pretreatment of trace Hg2+ detection.

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The Adsorption Properties of Microporous Activated Carbon Prepared from Pistachio Nut Shell for Low Concentration VOCs Under Low-medium Temperatures

10.21203/rs.3.rs-323143/v1 ◽

2021 ◽

Author(s):

Tangying Cheng ◽

Jinjin Li ◽

Xiuwei Ma ◽

Lei Zhou ◽

Hao Wu ◽

...

Keyword(s):

Activated Carbon ◽

Adsorption Process ◽

Size Structure ◽

Physical Adsorption ◽

High Surface ◽

High Surface Area ◽

Maximum Adsorption Capacity ◽

High Porosity ◽

Low Concentration ◽

Adsorption Performance

Abstract The control of low concentration VOCs in coal flue gas is one of the research hotspots at present. Activated carbon (AC) is often used as adsorbent for the control of VOCs due to its rich pore structure and thermal stability. In this paper, agricultural wastes pistachio shell was used as biomass AC raw materials, K2CO3 and KCl was used as activators. High surface area and high porosity activated carbon can be produced by the two activators used together. By comparing the differences in pore size structure and functional groups between biomass AC and commercial AC, it was found that biomass AC had better properties. The adsorption performance of different ACs on low concentration VOCs was tested at low-medium temperatures. It is concluded that biomass AC has excellent adsorption performance, and its maximum adsorption capacity can reach 3.8 times that of commercial AC. All the three adsorption kinetic models had good fitting on the adsorption process of ACs, indicating that physical adsorption is dominant in the adsorption process, while chemical adsorption existed. Using the Weber-Morris kinetic model to fit the adsorption process, it was found that the stage of external membrane mass transfer is the control stage of adsorption rate.

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