Removal of chlorophenols using industrial wastes.

Development of inexpensive adsorbents from industrial wastes for the treatment of wastewaters is an important area in environmental sciences. Blast furnace slag, dust and sludge from steel plants, and carbon slurry from fertilizer plants after their treatment have been utilized as inexpensive adsorbents for the removal of phenols, which are an important class of pollutants as they are highly toxic. The characterization of the four adsorbents prepared has shown that the carbonaceous adsorbent prepared from carbon slurry possesses high porosity and maximum surface area (380 m2/g) as compared to the other three adsorbents (4-28 m2/g). The adsorption of four phenols (phenol, 2-chlorophenol, 4-chlorophenol, and 2,4-dichlorophenol) on these adsorbents is parallel to their porosity and surface area order. The uptake of the phenols on carbonaceous adsorbent is substantial and found to be 17.2, 50.3, 57.4, and 132.5 mg/g for phenol, 2-chlorophenol, 4-chlorophenol, and 2,4-dichlorophenol, respectively. The detailed adsorption studies on carbonaceous adsorbent have indicated that the adsorption process follows the Langmuir isotherm, is first order, and is pore diffusion controlled. As adsorption of phenols on prepared carbonaceous adsorbent is significant, its performance has been evaluated with respect to standard activated charcoal. The results indicate that the phenols removal efficiency of carbonaceous adsorbent is about 45% to that of a standard activated charcoal sample. Thus, the carbonaceous adsorbent can be used for the removal of phenols as a low-cost alternative (approximately 0.1 U.S. dollars/kg) to activated charcoal.

A randomized controlled trial of cyanoacrylate versus alcohol injection in patients with isolated fundic varices.

OBJECTIVE: Treatment of bleeding gastric varices (GVs) is still controversial, mainly because of anecdotal studies or inclusion of patients with GVs located at different sites that have variable incidences of bleeding. A prospective study was undertaken to compare the efficacy and safety of GV sclerotherapy using alcohol and GV obturation using cyanoacrylate glue. METHODS: Thirty-seven consecutive patients with portal hypertension and endoscopic evidence of isolated GVs, 17 presenting with histories of active bleeding, were randomized to receive endoscopic intervention either with alcohol (n = 17) or with cyanoacrylate glue (n = 20) injection. Variceal obliteration, rebleeding, or death was the endpoint. RESULTS: The glue was significantly more effective in achieving variceal obliteration than alcohol (100% vs 44%, p < 0.05). Furthermore, this could be achieved in a significantly shorter period (2.0 +/- 1.6 vs 4.7 +/- 3.2 wk, p < 0.05) and with a smaller volume of the agent. Cyanoacrylate glue injection could achieve arrest of acute GV bleeding more often than alcohol (89% vs 62%), and the need for rescue surgery was less; the difference was, however, not significant. Six patients died from uncontrolled GV bleeding, four being in the alcohol group. During a mean follow-up of 15.4 +/- 3.7 months there was no recurrence of GVs in either group. CONCLUSIONS: Our results show that cyanoacrylate is more effective and achieves GV obliteration faster than injection sclerotherapy with alcohol. It also appears to be more useful in controlling acute GV bleeding, with less of a need for rescue surgery.