The solid-liquid interface reaction between phosphate rock (PR) and metals (Pb, Cu, and Zn) was studied. Phosphate rock has the highest affinity for Pb, followed by Cu and Zn, with sorption capacities of 138, 114, and 83.2 mmol/kg PR, respectively. In the Pb-Cu-Zn ternary system, competitive metal sorption occurred with sorption capacity reduction of 15.2%, 48.3%, and 75.6% for Pb, Cu, and Zn, respectively compared to the mono-metal systems. A fractional factorial design showed the interfering effect in the order of Pb>Cu>Zn. Desorption of Cu and Zn was sensitive to pH change, increasing with pH decline, whereas Pb desorption was decreased with a strongly acidic TCLP extracting solution (pH = 2.93). The greatest stability of Pb retention by PR can be attributed to the formation of insoluble fluoropyromorphite [Pb(10)(PO(4))(6)F(2)], which was primarily responsible for Pb immobilization (up to 78.3%), with less contribution from the surface adsorption or complexation (21.7%), compared to 74.5% for Cu and 95.7% for Zn. Solution pH reduction during metal retention and flow calorimetry analysis both supported the hypothesis of retention of Pb, Cu, and Zn by surface adsorption or complexation. Flow calorimetry indicated that Pb and Cu adsorption onto PR was exothermic, while Zn sorption was endothermic. Our research demonstrated that PR can effectively remove Pb from solutions, even in the presence of other heavy metals (e.g. Cu, Zn).

https://digitalcommons.calpoly.edu/cgi/viewcontent.cgi?article=1014&context=ersc_fac

Understanding the Mechanisms of Lead, Copper, and Zinc Retention by Phosphate Rock

The movement of drops in electric fields plays a role in processes as diverse as storm cloud formation, ink-jet printing and lab-on-a-chip manipulations. An important factor in practical applications is the tendency for adjacent drops to coalesce, usually assumed to be favoured if drops are oppositely charged and attracted to each other. Now Ristenpart et al. show that when oppositely charged drops move towards each other in an electric field whose strength exceeds a critical value, the drops simply 'bounce' off one another. This observation calls for a re-evaluation of our understanding of all processes involving electrically induced drop motion. Adjacent drops of fluid coalesce, and oppositely charged drops have long been assumed to experience an attractive force that favours their coalescence. However, here it is observed that oppositely charged drops moving towards each other in a strong electric field do not coalesce when the field strength exceeds a certain value but rather 'bounce' off one another. This observation calls for a re-evaluation of our understanding of processes such as storm cloud formation and ink-jet printing, which involve electrically induced droplet motion. Electric fields induce motion in many fluid systems, including polymer melts1, surfactant micelles2 and colloidal suspensions3. Likewise, electric fields can be used to move liquid drops4. Electrically induced droplet motion manifests itself in processes as diverse as storm cloud formation5, commercial ink-jet printing6, petroleum and vegetable oil dehydration7, electrospray ionization for use in mass spectrometry8, electrowetting9 and lab-on-a-chip manipulations10. An important issue in practical applications is the tendency for adjacent drops to coalesce, and oppositely charged drops have long been assumed to experience an attractive force that favours their coalescence11,12,13. Here we report the existence of a critical field strength above which oppositely charged drops do not coalesce. We observe that appropriately positioned and oppositely charged drops migrate towards one another in an applied electric field; but whereas the drops coalesce as expected at low field strengths, they are repelled from one another after contact at higher field strengths. Qualitatively, the drops appear to ‘bounce’ off one another. We directly image the transient formation of a meniscus bridge between the bouncing drops, and propose that this temporary bridge is unstable with respect to capillary pressure when it forms in an electric field exceeding a critical strength. The observation of oppositely charged drops bouncing rather than coalescing in strong electric fields should affect our understanding of any process involving charged liquid drops, including de-emulsification, electrospray ionization and atmospheric conduction.

http://absimage.aps.org/image/DFD09/MWS_DFD09-2009-001564.pdf

Non-coalescence of oppositely charged drops

Direct conversion of biomass to nanoporous activated biocarbons for high CO2 adsorption and supercapacitor applications

Product property and environmental risk assessment of heavy metals during pyrolysis of oily sludge with fly ash additive

A critical review on energy recovery and non-hazardous disposal of oily sludge from petroleum industry by pyrolysis

Experimental study on catalytic pyrolysis of oil sludge under mild temperature.

Study on a nitrogen-doped porous carbon from oil sludge for CO2 adsorption

With the enhancement of public awareness of environmental protection, the harm of oily sludge has gradually been paid attention to. As a kind of dangerous solid waste, the arbitrary disposal of oily sludge will cause quite serious harm to both the environment and human beings. Research on the treatment methods of oily sludge has become a hot spot recently. At present, treatment methods of oily sludge are various, mainly including pyrolysis, direct combustion, freeze-thaw treatment, biological treatment, solvent extraction, thermochemical cleaning, ultrasound-assisted treatment or joint technology, etc. Based on the consideration of economic benefits, social benefits and treatment difficulties, pyrolysis has been considered to be the most appropriate method for oily sludge treatment. Syngas, liquid oil and char can be obtained from pyrolysis of oily sludge, which can meet different needs. In this paper, the pyrolysis technology of oily sludge is reported in detail, including pyrolysis methods, operational parameters and pyrolysis products of oily sludge. On the basis, the advantages and limitations of oily sludge pyrolysis technology are discussed, together with the report of feasibility of pyrolysis technology of oily sludge. Moreover, the development trend of pyrolysis technology of oily sludge is prospected for the future work.

/pdf/application-and-development-of-pyrolysis-technology-in-2cjjqxvk0n.pdf

Application and development of pyrolysis technology in petroleum oily sludge treatment

Catalytic pyrolysis of chemical extraction residue from microalgae biomass

Oil sludge (OS) is a typical hazardous waste from the petrochemical industry. Currently, the increasing ratio of high-sulfur crude oil worldwide that results in the growth production of OS with hig...

Xiaoyu Li

Papers

Experimental study on catalytic pyrolysis of oil sludge under mild temperature.

Study on a nitrogen-doped porous carbon from oil sludge for CO2 adsorption

Application and development of pyrolysis technology in petroleum oily sludge treatment

Catalytic pyrolysis of chemical extraction residue from microalgae biomass

Study on the Migration Characteristics of Sulfur and Nitrogen during Combustion of Oil Sludge with CaO Additive