Pyrolysis Treatment of Chromite Ore Processing Residue by Biomass: Cellulose Pyrolysis and Cr(VI) Reduction Behavior.

The pyrolysis treatment with biomass is a promising technology for the remediation of chromite-ore-processing residue (COPR). However, the mechanism of this process is still unclear. In this study, the behavior of pyrolysis reduction of Cr(VI) by cellulose, the main component of biomass, was elucidated. The results showed that the volatile fraction (VF) of cellulose, ie. gas and tar, was responsible for Cr(VI) reduction. All organic compounds, as well as CO and H2 in VF, potentially reduced Cr(VI). X-ray absorption near-edge structure (XANES) spectroscopy and extended X-ray absorption fine-structure (EXAFS) spectroscopy confirmed the reduction of Cr(VI) to Cr(III) and the formation of amorphous Cr2O3. The remnant Cr(VI) content in COPR can be reduced below the detection limit (2 mg/kg) by the reduction of COPR particle and extension of reaction time between VF and COPR. This study provided a deep insight on the co-pyrolysis of cellulose with Cr(VI) in COPR and an ideal approach by which to characterize and optimize the pyrolysis treatment for COPR by other organics.

Phase I radioimmunotherapy trial with iodine-131--labeled humanized MN-14 anti-carcinoembryonic antigen monoclonal antibody in patients with metastatic gastrointestinal and colorectal cancer.

This trial was conducted to determine the pharmacokinetics, dosimetry, dose-limiting toxicity, and the maximum tolerated dose of iodine-131 humanized MN-14 immunoglobulin G (131I-hMN-14 IgG), a humanized complementary-determining region-grafted anti-carcinoembryonic antigen monoclonal antibody, in metastatic gastrointestinal and colorectal cancer patients. Patients were divided into 2 groups: group A consisted of patients who had prior external beam radiation therapy (n = 8), and group B included patients who had received standard chemotherapy (n = 13). All patients received a diagnostic infusion of 131I-hMN-14 IgG (approximately 8.0 mCi, 15 mg/m2) to study the pharmacokinetics, biodistribution, and dosimetry. One week later, 17 of 21 patients received infusional therapy of escalating radioactive doses of 131I-hMN-14 IgG. Blood pharmacokinetics and quantitative imaging were performed again after the therapeutic dose. Radiation-absorbed doses to normal organs and tumors were determined by MIRDOSE-3 algorithms. The primary dose-limiting toxicity was hematologic toxicity at 40 mCi/m2. The blood half-life (n = 20) was identical for the diagnostic and therapy infusions. The mean red marrow dose was 2.2 +/- 2.4 cGy/mCi. The mean tumor radiation dose (n = 8) was 24.2 +/- 22.6 cGy/mCi. Tumor targeting was seen in most large metastatic lesions. No objective responses were seen in these heavily pretreated and mostly advanced patients. In conclusion, 131I-hMN-14 IgG has good targeting, good tumor to normal organs radiation absorbed ratios, and an acceptable toxicity profile in advanced metastatic gastrointestinal and colorectal cancer patients.