Differentiating Inorganics in Biochars Produced at Commercial Scale Using Principal Component Analysis.

Characterizing the inorganic phase of biochar, beyond determining element concentration, is needed for appropriate application of these materials because mineral forms also influence element availability and behavior. Inorganics in 13 biochars (produced from Poultry litter, switchgrass, and different types of wood) were characterized by proximate analysis, chemical analysis, powder X-ray diffraction (XRD), and scanning electron microscopy with energy-dispersive X-ray (SEM-EDX) spectroscopy. Principal component analysis (PCA) was used to compare biochars and characterize associations between elements.

Initial biochar properties related to the removal of As, Se, Pb, Cd, Cu, Ni, and Zn from an acidic suspension.

This study tests the influence of a diverse set of biochar properties on As(V), Se(IV), Cd(II), Cu(II), Ni(II), Pb(II), or Zn(II) removal from solution at pH 4.5. Six commercial biochars produced using different feedstock and pyrolysis conditions were extensively characterized using physical, chemical, and spectroscopic techniques, and their properties were correlated to anion and cation removal using multiple linear regression.

Metal leaching in mine tailings: short-term impact of biochar and wood ash amendments.

Biochar is perceived as a promising amendment to reclaim degraded, metal-contaminated lands. The objective of this study was to compare the potential of biochar and wood ash amendments to reduce metal(loid) leaching in mine tailings. A 2-mo leaching experiment was conducted in duplicate on acidic and alkaline tailings, each mixed with 5 wt.

A review of the occurrence, analyses, toxicity, and biodegradation of naphthenic acids.

Naphthenic acids occur naturally in crude oils and in oil sands bitumens. They are toxic components in refinery wastewaters and in oil sands extraction waters. In addition, there are many industrial uses for naphthenic acids, so there is a potential for their release to the environment from a variety of activities.

Evaluation of the analyses of tert-butyldimethylsilyl derivatives of naphthenic acids by gas chromatography-electron impact mass spectrometry.

Naphthenic acids are a complex mixture of carboxylic acids with the general formula CnH(2n+Z)O2 and they are natural, toxic components of crude oils. GC-MS analyses of tert-butyldimethylsilyl esters of naphthenic acids are used to estimate component distribution within naphthenic acids mixtures. Our evaluations of the GC-MS method showed that ions from column bleed erroneously appear as C14 Z = -4 acids and that correcting for heavy isotopes of C and Si do not significantly affect ion distribution plots.

Aerobic biodegradation of two commercial naphthenic acids preparations.

Naphthenic acids (NAs) have a variety of commercial uses including as emulsifiers and wood preservatives. They have been identified as being the main component responsible for the acute toxicity in produced waters in the oil sands operations in northeastern Alberta, Canada. NAs comprise a complex mixture of alkyl-substituted acyclic and cycloaliphatic carboxylic acids, with the general chemical formula CnH(2n+Z)O2, where n indicates the carbon number and Z specifies hydrogen deficiency from ring formation.

A statistical comparison of naphthenic acids characterized by gas chromatography-mass spectrometry.

Naphthenic acids are complex mixtures of alkyl-substituted acyclic and cycloaliphatic carboxylic acids, with the general chemical formula C(n)H(2n+z)O(2), where n is the carbon number and Z specifies a homologous family. These acids have a variety of commercial uses, including being used as wood preservatives. They are found in conventional and heavy oils, and in the oil sands of northeastern Alberta, Canada.